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Preprint ARTICLE | doi:10.20944/preprints202207.0350.v1

Using the Vertical Distribution of Magnetic Susceptibility in the Assessment of Soil Condition in the Krakow Area, Southern Poland

Anna Wojas

Subject: Earth Sciences, Geophysics Keywords: magnetic susceptibility; soil magnetometry; vertical profiles; soil contamination; Krakow

Online: 25 July 2022 (05:36:35 CEST)

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The paper concerns the distribution of apparent magnetic susceptibility in soil profiles located in the areas of topsoil magnetic susceptibility anomalies in Krakow. The type of land use, possible sources of magnetic carriers, and the type of soil were taken into account. Additionally, at each soil profile, a comparison between soil magnetic susceptibility and the results of geochemical analyzes of soil samples was made. The study shows very characteristic changes in magnetic susceptibility with depth, reflecting the interdependencies between natural and anthropogenic factors. A visible magnetic susceptibility maximum at the depth of 10-30 cm is observed at each soil profile. The maximum is associated mainly with the deposition of atmospheric dust and its vertical range depends on the level of anthropopression and natural conditions of soils. At the depth above 40 cm in the eastern part of Krakow, a correlation between the magnetic susceptibility and the soil type (chernozems de-veloped on loess) was found. All indicates that the thicknesses of contaminated upper horizons are not accidental and they depend on human interactions with the environment and the type of soil. An attempt at template establishment with the sources of magnetic particle carriers for different places in the city was made. As the result, in high urbanized sites, the extreme values of magnet-ic susceptibility rapidly change in short vertical distances can identify the richness of anthropo-genic layers with various types of anthropogenic ferrous material and/or additionally Fe-carrying objects buried in soils. In industrialized sites, anthropogenic input plays the most important role in the creation of soil magnetic characteristics. What is more, industrial pollution hides the natural magnetic properties of chernozems. In opposite, the studies at the sites under low anthropopression (mainly located in forests) allow for better insight into magnetic proper-ties arising during pedogenic processes, indirectly giving information about soil conditions. In the forest areas, the lowest values of soil magnetic susceptibility were measured. Additionally, the influence of pedogenic and lithogenic factors on forest soils is manifested in the results. Among the sites concerned, particular attention should be paid to the vicinity of the steel plant because of the agricultural land in the surroundings.

Preprint ARTICLE | doi:10.20944/preprints202206.0251.v1

Contextual Accuracy Assessments for InSAR Methods Using Synthetic Data

Kelly Olsen, Matthew Calef, Piyush Agram

Subject: Earth Sciences, Geophysics Keywords: InSAR; deformation; synthetic data; ensemble methods; uncertainty estimate; time series analysis

Online: 17 June 2022 (08:57:52 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202206.0135.v1

Increasing the Lateral Resolution of 3D-GPR Datasets Through 2D-FFT Interpolation. Application to the Case Study of Roman Villa of Horta Da Torre (Fronteira, Portugal)

Rui Jorge Oliveira, Bento Caldeira, Teresa Teixidó, José Fernando Borges, André Carneiro

Subject: Earth Sciences, Geophysics Keywords: applied geophysics; digital signal processing; enhancement of sharpness of 3D-GPR datasets; 2D Fourier interpolation; GPR data densification

Online: 9 June 2022 (04:30:02 CEST)

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Preprint TECHNICAL NOTE | doi:10.20944/preprints202206.0097.v1

Assessing the Accuracy of Deformation Time Series Using an Automated InSAR Pipeline

Kelly M. Olsen, Matthew T. Calef, Piyush S. Agram

Subject: Earth Sciences, Geophysics Keywords: InSAR; deformation; validation; GPS; consistency

Online: 7 June 2022 (08:12:53 CEST)

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Preprint REVIEW | doi:10.20944/preprints202205.0227.v1

The Imprint of Recent Meteorological Events on Boulder Deposits along the Mediterranean Rocky Coasts

Marco Delle Rose, Paolo Martano

Subject: Earth Sciences, Geophysics Keywords: Coastal storm; Wind wave; Storm surge; Extreme coastal water level; Boulder dynamics; Geomorphological proxy; Interdisciplinary climate research

Online: 17 May 2022 (10:28:58 CEST)

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Preprint REVIEW | doi:10.20944/preprints202204.0226.v2

Paleomagnetic-Radiometric Mapping of the Transition Zone from Ocean to the Continent: A Review

Lev V. Eppelbaum, Youri I. Katz

Subject: Earth Sciences, Geophysics Keywords: paleomagnetic mapping; paleomagnetic profiling; radiometric dating; tectonic-structural interpretation; integrated study

Online: 5 May 2022 (05:00:57 CEST)

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Preprint REVIEW | doi:10.20944/preprints202204.0226.v1

Paleomagnetic-Radiometric Mapping of the Transition Zone from Ocean to the Continent: A Review

Lev V. Eppelbaum, Youri I. Katz

Subject: Earth Sciences, Geophysics Keywords: paleomagnetic mapping; paleomagnetic profiling; radiometric dating; tectonic-structural inter-pretation; integrated study

Online: 26 April 2022 (04:24:45 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202203.0361.v1

Monitoring the Microseismicity through a Dense Seismic Array and a Similarity Search Detection Technique: Application to the Gas-Storage Site of Collalto, North Italy

Antonio Scala, Guido Maria Adinolfi, Matteo Picozzi, Francesco Scotto di Uccio, Gaetano Festa, Grazia De Landro, Enrico Priolo, Stefano Parolai, Rosario Riccio, Marco Romanelli

Subject: Earth Sciences, Geophysics Keywords: Induced seismicity Monitoring; seismic arrays; sensor network technology; microearthquake detection

Online: 28 March 2022 (11:12:18 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202203.0041.v2

Reconstructing the 26 June 1917 Samoa Tsunami Disaster

Laura Sischka, Cyprien Bosserelle, Shaun Williams, Josephina Chan Ting, Ryan Paulik, Malcolm Whitworth, Lameko Talia, Paul Viskovic

Subject: Earth Sciences, Geophysics Keywords: coastal inundation; historical tsunami records; hazard exposure; impacts; BG-Flood; RiskScape

Online: 22 March 2022 (11:56:13 CET)

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The 26 June 1917 tsunamigenic earthquake in Samoa is considered the largest historical event on record to have impacted this region in terms of earthquake magnitude and intensity. Yet, very little is known about the scale and distribution of tsunami impacts compared with the recent 2009 event which originated about 150 km east along the subduction zone bend of the Northern Tonga Trench (NTT). In this study we set out to: 1) reconstruct the 1917 tsunami from source to inundation to understand its hazard risk characteristics in the Samoan islands of Savai’i and Upolu; and 2) assess the hazard implications of tsunamis sourced from different locations along the subduction zone bend of the NTT on present-day exposure of coastal assets relative to the 2009 tsunami benchmark. We use the BG-Flood numerical modelling suite to produce model outputs representing inundation extent and hazard depth intensities at spatially flexible grid resolution (10 m, 20 m and 40 m). These are validated using available tide gauge records in Apia harbour and limited observations of runup that were derived from historical records. We then combine the inundation model with available digital distributions of buildings in the RiskScape multi-hazard risk analysis software, to produce exposure metrics for understanding the likely impacts on present-day coastal asset and population distributions if a similar tsunami were to occur. Results of the tsunami modelling indicate variable modelled-to-observed consistency using available source models, wave and runup validation data. Discrepancies in recorded vs modelled wave arrival time at Apia of between 30—40 mins are observed, with modelled runup underestimated in southeast Upolu Island compared with the rest of the country where runup observations are available (e.g., Savai’i Island). These differences likely reflect complexities in the tsunami source mechanism which might not currently be represented in our modelling. Nevertheless, our results suggest that a larger proportion of people would be exposed in Savai’i island (71% of exposure total), compared with Upolu island if a characteristic 1917-type event were to occur. While this study provides the first detailed inundation model of the 1917 tsunami in the Samoan region, the observed discrepancies suggest that further investigation is required to constrain potential tsunami source complexities which might not be accounted for in this study. Notwithstanding these limitations, our findings help to reinforce an appreciation of the risk to the greater Samoan region faced by local tsunamis sourced at different locations along the subduction zone bend of the NTT.

Preprint ARTICLE | doi:10.20944/preprints202109.0521.v2

Challenges with Regard to Unmanned Aerial Systems (UASs) Measurement of River Surface Velocity Using Doppler Radar

Filippo Bandini, Monica Coppo Frías, Jun Liu, Kasparas Simkus, Sofia Karagkiolidou, Peter Bauer-Gottwein

Subject: Earth Sciences, Geophysics Keywords: UAS; drone; Doppler radar; PIV; river; velocity

Online: 7 March 2022 (14:55:21 CET)

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Preprint ARTICLE | doi:10.20944/preprints202203.0041.v1

Reconstructing the 26th June, 1917 Samoa Tsunami Disaster and Implications on Present-day Hazard Exposure

Laura Sischka, Cyprien Bosserelle, Shaun Williams, Josephina Chan Ting, Ryan Paulik, Malcolm Whitworth, Lameko Talia, Paul Viskovic

Subject: Earth Sciences, Geophysics Keywords: coastal inundation; historical tsunami records; hazard exposure; impacts; BG-Flood; RiskScape

Online: 2 March 2022 (10:07:49 CET)

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Preprint ARTICLE | doi:10.20944/preprints202201.0369.v1

Anomalous Geomagnetic Signal Emphasized Before the Mw8.2 Coastal Alaska Earthquake, Occurred on 29 July 2021

Dragoș Armand Stănică

Subject: Earth Sciences, Geophysics Keywords: geomagnetic polarization parameters; precursory geomagnetic; Mw8.2earthquake; CMO and NEW observatories -Alaska

Online: 25 January 2022 (08:30:54 CET)

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Preprint ARTICLE | doi:10.20944/preprints202112.0471.v1

A Fractal Description of Fluvial Networks in Chile: a Geography not as Crazy as Thought

Francisco Martinez, Hermann Manriquez, Alberto Ojeda, Gabriel Olea

Subject: Earth Sciences, Geophysics Keywords: fluvial networks; Chilean’s watersheds; monofractal dimension; morphometry; structural control

Online: 29 December 2021 (15:57:16 CET)

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Preprint ARTICLE | doi:10.20944/preprints202105.0014.v4

Investigation of the Time-Lapse Changes with the DAS Borehole Data at the Brady Geothermal Field Using Deconvolution Interferometry

Hilary Chang, Nori Nakata

Subject: Earth Sciences, Geophysics Keywords: Distributed Acoustic Sensing; Borehole; Time-Lapse

Online: 29 December 2021 (12:39:03 CET)

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Preprint ARTICLE | doi:10.20944/preprints202112.0220.v1

Finite-Element Modeling of Spontaneous Potential in an Axisymmetric Reservoir Model with Account of Its Shale Content

Mikhail Epov, Anastasia Glinskikh, Oleg Nechaev

Subject: Earth Sciences, Geophysics Keywords: spontaneous potential logging; electrochemical potential; finite element method; numerical modelling; synthetic and practical data; clayey sandstone reservoir

Online: 14 December 2021 (08:01:45 CET)

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Preprint ARTICLE | doi:10.20944/preprints202112.0169.v1

Characterisation of the Dynamics of Leachate Contamination Plumes in the Surrounding of the Hulene - B Waste Dump, Maputo, Mozambique

Bernardino Bernardo, Carla Candeias, Fernando Rocha

Subject: Earth Sciences, Geophysics Keywords: Plumes; dynamics; resistivity; contamination; groundwater

Online: 10 December 2021 (11:28:20 CET)

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Preprint ARTICLE | doi:10.20944/preprints202112.0013.v1

Estimating Water Content in Water-oil Mixtures and Porous Media they Saturate: Joint Interpretation of NMR Relaxometry and Dielectric Spectroscopy

Mariya Shumskayte, Andrey Mezin, Elena Chernova, Aleksandra Burukhina, Nikita Golikov, Svetlana Melkozerova

Subject: Earth Sciences, Geophysics Keywords: nuclear magnetic resonance; dielectric spectroscopy; water-oil mixture; relaxation characteristic; drill cuttings; West Siberia

Online: 1 December 2021 (12:53:32 CET)

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Preprint ARTICLE | doi:10.20944/preprints202111.0422.v1

Real-Time Tephra Detection and Dispersal Forecasting by a Ground-Based Weather Radar

Magfira Syarifuddin, Susanna F. Jenkins, Ratih Indri Hapsari, Qingyuan Yang, Benoit Taisne, Andika Bayu Aji, Nurnaning Aisyah, Hanggar Ghanara Mawanda, Djoko Legono

Subject: Earth Sciences, Geophysics Keywords: tephra; ground-based weather radar; Bayesian approach; nowcasting; ensemble prediction system

Online: 23 November 2021 (13:00:31 CET)

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Preprint ARTICLE | doi:10.20944/preprints202105.0014.v3

Investigation of the Time-Lapse Changes with the DAS Borehole Data at the Brady Geothermal Field Using Deconvolution Interferometry

Hilary Chang, Nori Nakata

Subject: Earth Sciences, Geophysics Keywords: Distributed Acoustic Sensing; Borehole; Time-Lapse

Online: 8 November 2021 (13:15:26 CET)

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Preprint ARTICLE | doi:10.20944/preprints202111.0099.v1

Experimental Estimation of Deviation Frequency Within the Spectrum of Scintillations of the Carrier Phase of GNSS Signals

Vladislav Demyanov, Ekaterina Danilchuk, Yury Yasyukevich, Maria Sergeeva

Subject: Earth Sciences, Geophysics Keywords: ionosphere; scintillations; carrier phase; GNSS; GPS; GLONASS; Galileo; SBAS; GNSS signals; deviation frequency

Online: 4 November 2021 (09:41:04 CET)

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Preprint ARTICLE | doi:10.20944/preprints202110.0261.v1

On the Potential of 3D Transdimensional Surface Wave Tomography for Geothermal Prospecting of the Reykjanes peninsula

Amin Rahimi Dalkhani, Xin Zhang, Cornelis Weemstra

Subject: Earth Sciences, Geophysics Keywords: Seismic interferometry; Transdimensional tomography; Surface wave dispersion; probabilistic inversion; Markov chain Monte Carlo

Online: 19 October 2021 (08:23:56 CEST)

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Seismic travel time tomography using surface waves is an effective tool for three-dimensional crustal imaging. Historically, these surface waves are the result of active seismic sources or earthquakes. More recently, however, also surface waves retrieved through the application of seismic interferometry are exploited. Conventionally, two-step inversion algorithms are employed to solve the tomographic inverse problem. That is, a first inversion results in frequency-dependent, two-dimensional maps of phase velocity, which then serve as input for a series of independent, one-dimensional frequency-to-depth inversions. As such, a two-dimensional grid of localized depth-dependent velocity profiles are obtained. Stitching these separate profiles together subsequently yields a three-dimensional velocity model. Relatively recently, a one-step three-dimensional non-linear tomographic algorithm has been proposed. The algorithm is rooted in a Bayesian framework using Markov chains with reversible jumps, and is referred to as transdimensional tomography. Specifically, the three-dimensional velocity field is parameterized by means of a polyhedral Voronoi tessellation. In this study, we investigate the potential of this algorithm for the purpose of recovering the three-dimensional surface-wave-velocity structure from ambient noise recorded on and around the Reykjanes Peninsula, southwest Iceland. To that end, we design a number of synthetic tests that take into account the station configuration of the Reykjanes seismic network. We find that the algorithm is able to recover the 3D velocity structure at various scales in areas where station density is high. In addition, we find that the standard deviation on the recovered velocities is low in those regions. At the same time, the velocity structure is less well recovered in parts of the peninsula sampled by fewer stations. This implies that the algorithm successfully adapts model resolution to the density of rays. Also, it adapts model resolution to the amount of noise on the travel times. Because the algorithm is computationally demanding, we modify the algorithm such that computational costs are reduced while sufficiently preserving non-linearity. We conclude that the algorithm can now be applied adequately to travel times extracted from (time-averaged) station-station cross correlations by the Reykjanes seismic network.

Preprint ARTICLE | doi:10.20944/preprints202110.0122.v2

Airborne Validation of ICESat-2 ATLAS Data Over Crevassed Surfaces and Other Complex Glacial Environments: Results From Experiments of Laser Altimeter and Kinematic GPS Data Collection From a Helicopter Over a Surging Arctic Glacier (Negribreen, Svalbard)

Ute Christina Herzfeld, Matthew Lawson, Thomas Trantow, Thomas Nylen

Subject: Earth Sciences, Geophysics Keywords: ICESat-2; Laser Altimetry; Kinematic GPS Experiments; Glaciology; Surge Glaciers; Svalbard; Density Dimension Algorithm for Ice Surfaces; Airborne Validation of Satellite Data

Online: 13 October 2021 (10:45:21 CEST)

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The topic of this paper is the airborne evaluation of ICESat-2 Advanced Topographic Laser Altimeter System (ATLAS) measurement capabilities and surface-height-determination over crevassed glacial terrain, with a focus on the geodetical accuracy of geophysical data collected from a helicopter. To obtain surface heights over crevassed and otherwise complex ice surface, ICESat-2 data are analyzed using the density-dimension algorithm for ice surfaces (DDA-ice), which yields surface heights at the nominal 0.7~m along-track spacing of ATLAS data. As the result of an ongoing surge, Negribreen, Svalbard, provided an ideal situation for the validation objectives in 2018 and 2019, because many different crevasse types and morphologically complex ice surfaces existed in close proximity. Airborne geophysical data, including laser altimeter data (profilometer data at 905~nm frequency), differential Global Positioning System (GPS), Inertial Measurement Unit (IMU) data, on-board-time-lapse imagery and photographs, were collected during two campaigns in summers of 2018 and 2019. Airborne experiment setup, geodetical correction and data processing steps are described here. To date, there is relatively little knowledge of the geodetical accuracy that can be obtained from kinematic data collection from a helicopter. Our study finds that (1)~Kinematic GPS data collection with correction in post-processing yields higher accuracies than Real-Time-Kinematic (RTK) data collection. (2)~Processing of only the rover data using the Natural Resources Canada Spatial Reference System Precise Point Positioning (CSRS-PPP) software is sufficiently accurate for the sub-satellite validation purpose. (3)~Distances between ICESat-2 ground tracks and airborne ground tracks were generally better than 25~m, while distance between predicted and actual ICESat-2 ground track was on the order of 9~m, which allows direct comparison of ice-surface heights and spatial statistical characteristics of crevasses from the satellite and airborne measurements. (4)~The Lasertech Universal Laser System (ULS), operated at up to 300~m above ground level, yields full return frequency (400~Hz) and 0.06-0.08~m on-ice along-track spacing of height measurements. (5)~Cross-over differences of airborne laser altimeter data are 0.1918 $\pm$ 2.385~m along straight paths over generally crevassed terrain, which implies a precision of approximately 2.4~m for ICESat-2 validation experiments. (6)~In summary, the comparatively light-weight experiment setup of a suite of small survey equipment mounted on a Eurocopter (Helicopter AS-350) and kinematic GPS data analyzed in post-processing using CSRS-PPP leads to high accuracy repeats of the ICESat-2 tracks. The technical results (1)-(6) indicate that direct comparison of ice-surface heights and crevasse depths from the ICESat-2 and airborne laser altimeter data is warranted. The final result of the validation is that ICESat-2 ATLAS data, analyzed with the DDA-ice, facilitate surface-height determination over crevassed terrain, in good agreement with airborne data, including spatial characteristics, such as surface roughness, crevasse spacing and depth, which are key informants on the deformation and dynamics of a glacier during surge.

Preprint ARTICLE | doi:10.20944/preprints202110.0122.v1

Airborne Validation of ICESat-2 ATLAS Data Over Crevassed Surfaces and Other Complex Glacial Environments: Results From Experiments of Laser Altimeter and Kinematic GPS Data Collection From a Helicopter Over a Surging Arctic Glacier (Negribreen, Svalbard)

Ute Christina Herzfeld, Matthew Lawson, Thomas Trantow, Thomas Nylen

Subject: Earth Sciences, Geophysics Keywords: ICESat-2; Laser Altimetry; Kinematic GPS Experiments; Glaciology; Surge Glaciers; Svalbard; Density Dimension Algorithm for Ice Surfaces; Airborne Validation of Satellite Data

Online: 7 October 2021 (15:13:55 CEST)

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The topic of this paper is the airborne evaluation of ICESat-2 Advanced Topographic Laser Altimeter System (ATLAS) measurement capabilities and surface-height-determination over crevassed glacial terrain, with a focus on the geodetical accuracy of geophysical data collected from a helicopter. To obtain surface heights over crevassed and otherwise complex ice surface, ICESat-2 data are analyzed using the density-dimension algorithm for ice surfaces (DDA-ice), which yields surface heights at the nominal 0.7~m along-track spacing of ATLAS data. As the result of an ongoing surge, Negribreen, Svalbard, provided an ideal situation for the validation objectives in 2018 and 2019, because many different crevasse types and morphologically complex ice surfaces existed in close proximity. Airborne geophysical data, including laser altimeter data (profilometer data at 905~nm frequency), differential Global Positioning System (GPS), Inertial Measurement Unit (IMU) data, on-board-time-lapse imagery and photographs, were collected during two campaigns in summers of 2018 and 2019. Airborne experiment setup, geodetical correction and data processing steps are described here. To date, there is relatively little knowledge of the geodetical accuracy that can be obtained from kinematic data collection from a helicopter. Our study finds that (1)~Kinematic GPS data collection with correction in post-processing yields higher accuracies than Real-Time-Kinematic (RTK) data collection. (2)~Processing of only the rover data using the Natural Resources Canada Spatial Reference System Precise Point Positioning (CSRS-PPP) software is sufficiently accurate for the sub-satellite validation purpose. (3)~Distances between ICESat-2 ground tracks and airborne ground tracks were generally better than 25~m, while distance between predicted and actual ICESat-2 ground track was on the order of 9~m, which allows direct comparison of ice-surface heights and spatial statistical characteristics of crevasses from the satellite and airborne measurements. (4)~The Lasertech Universal Laser System (ULS), operated at up to 300~m above ground level, yields full return frequency (400~Hz) and 0.06-0.08~m on-ice along-track spacing of height measurements. (5)~Cross-over differences of airborne laser altimeter data are 0.1918 $\pm$ 2.385~m along straight paths over generally crevassed terrain, which implies a precision of approximately 2.4~m for ICESat-2 validation experiments. (6)~In summary, the comparatively light-weight experiment setup of a suite of small survey equipment mounted on a Eurocopter (Helicopter AS-350) and kinematic GPS data analyzed in post-processing using CSRS-PPP leads to high accuracy repeats of the ICESat-2 tracks. The technical results (1)-(6) indicate that direct comparison of ice-surface heights and crevasse depths from the ICESat-2 and airborne laser altimeter data is warranted. The final result of the validation is that ICESat-2 ATLAS data, analyzed with the DDA-ice, facilitate surface-height determination over crevassed terrain, in good agreement with airborne data, including spatial characteristics, such as surface roughness, crevasse spacing and depth, which are key informants on the deformation and dynamics of a glacier during surge.

Preprint CASE REPORT | doi:10.20944/preprints202110.0047.v1

The Mechanism of Destruction Under the Influence of Shock Waves

Igor Shcherbakov, Khairullo Makhmudov

Subject: Earth Sciences, Geophysics Keywords: shock waves; mechanism and dynamics of destruction; quartz; granites; calcite

Online: 4 October 2021 (11:03:20 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202109.0521.v1

Measuring River Surface Velocity with Doppler Radar and Particle Image Velocimetry (PIV) Using Unmanned Aerial Systems (UASs)

Filippo Bandini, Monica Coppo Frias, Jun Liu, Kasparas Simkus, Sofia Karagkiolidou, Peter Bauer-Gottwein

Subject: Earth Sciences, Geophysics Keywords: UAS; drone; Doppler radar; PIV; river; velocity

Online: 30 September 2021 (14:53:11 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202109.0406.v1

An Array Multi-Physics Acquisition System with Focus on Reservoir Monitoring

Kurt Martin Strack, Andri Yadi Paembonan, Sofia N. Davydycheva, Tilman Hanstein, Maxim Y Smirnov

Subject: Earth Sciences, Geophysics Keywords: Array electromagnetics, magnetotellurics, controlled source electromagnetics, microseismics, reservoir monitoring, enhanced oil recovery, recovery factor improvement

Online: 23 September 2021 (12:27:38 CEST)

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Working Paper ARTICLE

Investigation of the Time-Lapse Changes with the DAS Borehole Data at the Brady Geothermal Field Using Deconvolution Interferometry

Hilary Chang, Nori Nakata

Subject: Earth Sciences, Geophysics Keywords: Distributed Acoustic Sensing; Borehole; Time-Lapse

Online: 29 June 2021 (11:49:00 CEST)

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The distributed acoustic sensing (DAS) has great potential for monitoring natural-resource reservoirs as well as borehole conditions. However, the large volume of data, complicated wavefield, and higher noise level often make processing and interpretation difficult. To this end, seismic interferometry based on deconvolution becomes a convenient tool for analyzing complex wavefield and extracting coherent waves from noise. It separates the structure response and allows us to examine the wavefields that satisfy different boundary conditions. Thus, we can utilize the dense spatial coverage of DAS receivers deployed in the borehole for monitoring structural changes, diagnosing well-casing integrity, and constrain the seismic energy sources in space and time. We apply this technique on the DAS data in the vertical borehole at the Brady geothermal field in Nevada to extract coherent and interpretable waves. Using results from analytical and numerical modeling, we discover that a simple string model can explain the extracted coherent waves well. By analyzing the strong reverberating signals due to resonance of the upper borehole casing with this numerical model, we constrain the dominant energy sources in the system and the configuration of the structure that causes the resonance. We investigate the propagating velocity of the extracted waves as well as the velocity variation with depth, observation time, temperature, and pressure. The velocity variations due to these parameters suggest that the waves are sensitive to thermal condition, casing condition, and borehole processes induced by pressure changes. The amplitude spectra of the deconvolved wavefields show clear normal modes of such reverberations, which are useful for dispersion analysis of the waves. At the bottom half of the borehole, which does not show clear resonance, we only obtain signals during the active seismic operation time due to poor coupling. To extract the time-lapse changes of formation, we need better coupling between DAS cables and the borehole.

Preprint ARTICLE | doi:10.20944/preprints202104.0412.v1

Can Deep Learning Extract Useful Information about Energy Dissipation and Effective Hydraulic Conductivity from Gridded Conductivity Fields?

Mohammad Abdolhosseini Moghaddam, Ty Paul Andrew Ferré, Jeffrey Klakovich, Hoshin Vijay Gupta, Mohammad Reza Ehsani

Subject: Earth Sciences, Geophysics Keywords: deep learning; hydraulic conductivity; convolutional neural networks; groundwater

Online: 15 April 2021 (12:25:05 CEST)

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Working Paper ARTICLE

Possible Correlations Between the ULF Geomagnetic Signature and Mw6.4 Coastal Earthquake, Albania, on 26 November 2019

Dragoș Armand Stănică, Dumitru Stănică

Subject: Earth Sciences, Geophysics Keywords: ULFgeomagnetic signature, Mw6.4 earthquake, geomagnetic data, BPOL, BPOL* and BPOL*(PAG-SUA) time series

Online: 15 January 2021 (12:57:21 CET)

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Working Paper ARTICLE

Accuracy of a Model-Free Algorithm for Temporal InSAR Tropospheric Correction

Howard Zebker

Subject: Earth Sciences, Geophysics Keywords: InSAR; InSAR calibration/validation; atmosphere/troposphere variations

Online: 21 December 2020 (12:34:10 CET)

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Preprint ARTICLE | doi:10.20944/preprints202012.0392.v1

Allocation of Potential Emergency Sections on Pipelines

Emiliia Iakovleva, Margarita Belova, Amilcar Soares

Subject: Earth Sciences, Geophysics Keywords: Earth’s natural pulse electromagnetic field; stress-strain state of rock mass; magnetic field strength; magnetic induction; pipeline; measurement; accident; civil communication

Online: 15 December 2020 (19:52:19 CET)

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Preprint ARTICLE | doi:10.20944/preprints202012.0248.v1

Pulsed Electromagnetic Cross-well Exploration for Monitoring Permafrost and Examining the Processes of Its Geocryological Changes

Viacheslav Glinskikh, Oleg Nechaev, Igor Mikhaylov, Kirill Danilovskiy, Vladimir Olenchenko

Subject: Earth Sciences, Geophysics Keywords: cryolithozone; geophysical monitoring; pulsed electromagnetic sounding; cross-well exploration; vector finite-element method; numerical simulation; high-performance computing

Online: 10 December 2020 (10:39:26 CET)

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Preprint ARTICLE | doi:10.20944/preprints202009.0080.v1

Spatio – Temporal Characteristics of the Aftershocks Sequences that followed the Strong Earthquakes in Ionian Islands, Greece

Alexandra Moshou, George Drakatos, Vassilios Moussas, Panagiotis Argyrakis, Antonios Konstantaras, Anna Christina Daverona, Dimos Pantazis, Nikos C. Sagias

Subject: Earth Sciences, Geophysics Keywords: earthquake; source observations; body wave modeling; seismicity; ionian sea; gnss; machine learning; neural network

Online: 4 September 2020 (04:08:49 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202008.0590.v1

The MW = 5.6 Kanallaki Earthquake of March 21, 2020 in West Epirus, Greece: Reverse Fault Model From Insar Data and Seismotectonic Implications for Apulia-Eurasia Collision

Sotiris Valkaniotis, Pierre Briole, Athanassios Ganas, Panagiotis Elias, Vasilis Kapetanidis, Varvara Tsironi, Anna Fokaefs, Helena Partheniou, Panagiotis Paschos

Subject: Earth Sciences, Geophysics Keywords: deformation; earthquake; InSAR; inversion; fault; convergence; Apulia; Epirus; Greece

Online: 27 August 2020 (04:06:29 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202008.0559.v1

Fluid identification method and adaptability analysis of ultra-low porosity tight sandstone in Kuqa Depression, Tarim Basin

Maojin Tan, Chengwen Xiao, Chuang Han, Bo Li, Weiping Luo, Andong Wang, Qian Wang

Subject: Earth Sciences, Geophysics Keywords: Ultra-low porosity tight sandstone; fluid identification; NMR logging; triple-porosity comprehensive method; integrated method

Online: 26 August 2020 (04:22:18 CEST)

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Preprint COMMUNICATION | doi:10.20944/preprints202008.0011.v1

Enhancing Electrical Contact with a Commercial Polymer for Electrical Resistivity Tomography on Archaeological Sites: A Case Study

Marco D. Vásconez-Maza, Pedro Martínez-Pagán, Hasan Aktarakçi, María C. García-Nieto, Marcos A. Martínez-Segura

Subject: Earth Sciences, Geophysics Keywords: electrical resistivity tomography (ERT) method; polymer; carbomer; ground-electrode electrical contact enhancement; archaeology

Online: 2 August 2020 (10:58:15 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202007.0323.v1

Multiple Scattering Theory for Strong Scattering Heterogeneous Elastic Continua with Triaxial Inhomogeneities: Theoretical Fundamentals and Applications

Huijing He

Subject: Earth Sciences, Geophysics Keywords: scattering; heterogeneity; anisotropy; elastic waves; dispersion; attenuation; Mohorovičić discontinuity

Online: 15 July 2020 (09:01:02 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202007.0165.v1

Effects of Water Level Decline in Lake Urmia, Iran, on Local Climate Conditions

Amir Hossein Dehghanipour, Davood Moshir Panahi, Hossein Mousavi, Zahra Kalantari, Massoud Tajrishy

Subject: Earth Sciences, Geophysics Keywords: Lake Urmia; Local climate; Temperature adjustment; lake/land breeze

Online: 9 July 2020 (02:07:35 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202006.0127.v1

Mapping of Agricultural Subsurface Drainage Systems Using a Frequency-Domain Ground Penetrating Radar and Evaluating Its Performance Using a Single-Frequency Multi-Receiver Electromagnetic Induction Instrument

Triven Koganti, Ellen Van De Vijver, Barry J. Allred, Mogens H. Greve, Jørgen Ringgaard, Bo V. Iversen

Subject: Earth Sciences, Geophysics Keywords: frequency-domain; ground penetrating radar; electromagnetic induction; penetration depth; inversion; non-destructive techniques; agricultural drainage systems

Online: 10 June 2020 (05:39:04 CEST)

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Subsurface drainage systems remove excess water from the soil profile thereby improving crop yields in poorly drained farmland. Knowledge of the position of the buried drain lines is important: 1) to improve understanding of leaching and offsite release of nutrients and pesticides, and 2) for the installation of a new set of drain lines between the old ones for enhanced soil water removal efficiency. Traditional methods of drainage mapping involve the use of tile probes and trenching equipment. While these can be effective, they are also time-consuming, labor-intensive, and invasive, thereby entailing an inherent risk of damaging the drainpipes. Non-invasive geophysical soil sensors provide a potential alternative solution. Previous research has focused on the use of time-domain ground penetrating radar (GPR), with variable success depending on local soil and hydrological conditions and the central frequency of the specific equipment employed. The objectives of this study were 1) to test the use of a stepped-frequency continuous wave (SFCW) 3D-GPR (GeoScope Mk IV 3D-Radar with DXG1820 antenna array) for subsurface drainage mapping, and 2) to evaluate the performance of a 3D-GPR with the use of a single-frequency multi-receiver electromagnetic induction (EMI) sensor (DUALEM) in-combination. The 3D-GPR system offers more flexibility for application to different (sub)surface conditions due to the coverage of wide frequency bandwidth. The EMI sensor simultaneously provides information about the apparent electrical conductivity (EC_a) for different soil volumes, corresponding to different depths. This sensor combination was evaluated on twelve different study sites with various soil types with textures ranging from sand to clay till. While the 3-D GPR showed a high success rate in finding the drainpipes at five sites (sandy, sandy loam, loamy sand, and organic topsoils), the results at the other seven sites were less successful due to limited penetration depth (PD) of the 3D-GPR signal. The results suggest that the electrical conductivity estimates produced by the inversion of EC_a data measured by the DUALEM sensor could be a useful proxy to explain the success achieved by the 3D-GPR in finding the drain lines. The high attenuation of electromagnetic waves in highly conductive media limiting the PD of the 3D-GPR can explain the findings obtained in this research.

Preprint ARTICLE | doi:10.20944/preprints202005.0412.v1

Τhe February – March 2019 Seismic Swarm Offshore North Lefkada Island, Greece: Microseismicity Analysis and Geodynamic Implications

Anastasios Kostoglou, Vassilios Karakostas, Polyzois Bountzis, Eleftheria Papadimitriou

Subject: Earth Sciences, Geophysics Keywords: seismic swarm; relocated aftershocks; transition zone; b-value temporal variation; central Ionian Islands (Greece)

Online: 25 May 2020 (16:47:35 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202001.0377.v1

Electrical Resistivity Tomography as a Support Tool to Estimate Physicochemical Properties of Mining Tailings Pond

María Gabarrón, Pedro Martínez-Pagán, Marcos A. Martínez-Segura, Silvia Martínez-Martínez, Ángel Faz, Jose A. Acosta

Subject: Earth Sciences, Geophysics Keywords: ERT method; regression model; tailings pond; heavy metal; reclamation

Online: 31 January 2020 (05:04:37 CET)

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Preprint ARTICLE | doi:10.20944/preprints202001.0023.v1

Global Spatial Relationship between Land Use Land Cover and Land Surface Temperature

Azad Rasul

Subject: Earth Sciences, Geophysics Keywords: Land Use Land Cover (LULC); Land Surface Temperature (LST); Google Earth Engine (GEE); relationship; remote sensing indices; MODIS; global

Online: 3 January 2020 (05:03:05 CET)

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Preprint ARTICLE | doi:10.20944/preprints201912.0359.v1

Identifying the Frequency Dependent Interactions Between Ocean Waves and The Continental Margin on Seismic Noise Recordings

Zhen Guo, Yu Huang, Adnan Aydin, Mei Xue

Subject: Earth Sciences, Geophysics Keywords: ocean waves; double-frequency microseisms; continental margin; continental slope

Online: 27 December 2019 (07:59:29 CET)

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Preprint ARTICLE | doi:10.20944/preprints201912.0177.v1

The Akimotoite--Majorite--Bridgmanite Triple Point Determined in Large Volume Press and Laser-Heated Diamond Anvil Cell

Britany Kulka, Jonathan Dolinschi, Kurt Leinenweber, Vitali Prakapenka, Sang-Heon Shim

Subject: Earth Sciences, Geophysics Keywords: triple point; bridgmanite; akimotoite; majorite; large-volume press; laser-heated diamond anvil cell

Online: 12 December 2019 (12:47:47 CET)

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Preprint ARTICLE | doi:10.20944/preprints201911.0254.v1

Mean Zonal Drift Velocities of Plasma Bubbles Estimated from Keograms of Nightglow All-Sky Images from the Brazilian Sector

Fabio Vargas, Christiano Brum, Pedrina Terra, Delano Gobbi

Subject: Earth Sciences, Geophysics Keywords: all-sky imager; ionospheric plasma bubble; zonal drift velocity; keograms; nightglow; OI6300 thermospheric emission

Online: 22 November 2019 (05:42:49 CET)

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Preprint ARTICLE | doi:10.20944/preprints201910.0341.v1

Near-Real Time Automatic Snow Avalanche Activity Monitoring System Using Sentinel-1 SAR Data in Norway

Markus Eckerstorfer, Hannah Vickers, Eirik Malnes, Jakob Grahn

Subject: Earth Sciences, Geophysics Keywords: SAR; Sentinel-1; snow avalanche; automatic detection

Online: 29 October 2019 (15:37:11 CET)

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Working Paper ARTICLE

Satellite Retrieval of Downwelling Shortwave Surface Flux and Diffuse Fraction under All Sky Conditions in the Framework of the LSA SAF Program (Part 2: Evaluation)

Dominique Carrer, Suman Moparthy, Chloé Vincent, Xavier Ceamanos, Sandra C. Freitas, Isabel F. Trigo

Subject: Earth Sciences, Geophysics Keywords: solar radiation; meteosat second generation; validation; land surface modelling

Online: 27 October 2019 (04:25:31 CET)

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Preprint ARTICLE | doi:10.20944/preprints201910.0232.v1

Satellite Retrieval of Downwelling Shortwave Surface Flux and Diffuse Fraction under All Sky Conditions in the Framework of the LSA SAF Program (Part 1: Methodology)

Dominique Carrer, Xavier Ceamanos, Suman Moparthy, Chloe Vincent, Sandra C. Freitas, Isabel Trigo

Subject: Earth Sciences, Geophysics Keywords: solar radiation; diffuse; LSA SAF; aerosols; MSG SEVIRI; open source code

Online: 20 October 2019 (02:24:07 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201910.0202.v1

Sea Level Rise Scenario for 2100 A.D. in the Heritage Site of Pyrgi (Santa Severa, Italy)

Marco Anzidei, Fawzi Doumaz, Antonio Vecchio, Enrico Serpelloni, Luca Pizzimenti, Riccardo Civico, Flavio Enei

Subject: Earth Sciences, Geophysics Keywords: sea level rise; coastlines; 2100; heritage sites; Pyrgi; Mediterranean; UAV; DSM

Online: 17 October 2019 (14:56:12 CEST)

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Working Paper ARTICLE

Viscoelastic Behaviour from Complementary Forced-Oscillation and Micro-Creep Tests

Ian Jackson

Subject: Earth Sciences, Geophysics Keywords: viscoelasticity; anelasticity; creep function; forced-oscillation methods; micro creep methods

Online: 13 October 2019 (16:55:05 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201910.0123.v1

Assessment of Integrated Water Vapor Estimates from the iGMAS and the Brazilian Network GNSS Ground-Based Receivers in Rio de Janeiro

Galdino V. Mota, Shuli Song, Katarzyna Stępniak

Subject: Earth Sciences, Geophysics Keywords: IWV; GNSS; iGMAS; RBMC; meteorological data; MODIS; radiosonde; Rio de Janeiro

Online: 11 October 2019 (03:52:06 CEST)

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There is crescent demand for knowledge improvement of the integrated water vapor (IWV) distribution in regions affected by heat islands that are associated with extreme rainfall events such as in the metropolitan area of Rio de Janeiro (MARJ). This work assessed the suitability and distribution of IWV in the MARJ using products from the Global Navigation Satellite Systems (GNSS), MODerate Resolution Imaging Spectroradiometer (MODIS), and radiosonde. GNSS data were collected by the tracking station named RDJN, from the cooperation of the International GNSS Monitoring and Assessment System (iGMAS) and the National Observatory of Brazil (Observatório Nacional - ON), and the tracking stations ONRJ, RIOD, and RJCG belonging to the Brazilian Network for Continuous Monitoring (RBMC) in the period of January 2015–August 2018. High variability of the near surface air temperature (T) and relative humidity (RH) were observed among eight meteorological sites considered. The mean T differences between sites, up to 4.4 °C, led to mean differences as high as 3.1 K for weighted mean temperature (Tm) and hence 0.83 mm for IWV differences. The performance of the MODIS MOD07 and MYD07 products provided a reasonably good representation of the mean spatial distribution of IWV, especially during the daylight passages of the satellites TERRA and AQUA. Local grid points of MODIS IWV estimates had relatively good agreement with the GNSS-derived IWV, with mean differences from -2.4–1.1 mm considering only daytime passages of the satellites TERRA and AQUA. During nighttime, MODIS underestimated IWV (from -9–-3 mm) with respect to GNSS, due to attenuation of IR radiation by clouds. A contrasting behavior was found in the radiosonde IWV estimates compared with the estimates from GNSS. There were dry biases of 1.4 mm (3.7% lower than expected) by radiosonde IWV during the daytime considering that all other estimates were unbiased and the differences between IWV GNSS and IWV RADS were consistent. Based on the IWV comparisons between radiosonde and GNSS at nighttime, the atmosphere over the radiosonde site is about 1.2 (2.3) mm wetter than over RIOD (RDJN) station. The long time series of the comparisons between IWVRDJN and IWVRIOD showed that the highest values of IWV occurred from the afternoon to nocturnal hours. Further, the atmosphere over the site RIOD was consistently about 1 mm wetter than over RDJN. These results showed the feasibility of the iGMAS RDJN station data compared with the RBMC, MODIS, and radiosonde data to investigate IWV in a region with occurrence of heat islands, and the peculiar physiographic and meteorological characteristics as in the MARJ. This work recommended the usage of complete meteorological station data collocated near every GNSS receiver aiming improvements of local GNSS IWV estimates and serving as additional support for operational numerical assimilation, weather forecast, and nowcast of extreme rainfall events.

Preprint ARTICLE | doi:10.20944/preprints201910.0023.v1

Correlation of Elastic Moduli and Serpentine Content in Ultramafic Rocks

Aida Farough, Alexander Karrasch

Subject: Earth Sciences, Geophysics Keywords: serpentinization; elastic moduli; density; ultramafic rocks; oceanic lithosphere

Online: 2 October 2019 (06:28:08 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201908.0298.v1

Watching the Beach Steadily Disappearing – the Evolution of Understanding of Retrogressive Breach Failures

Dick R. Mastbergen, Konrad Beinssen, Yves Nédélec

Subject: Earth Sciences, Geophysics Keywords: coastal erosion; beach morphodynamics; beach erosion; flow slide; slope instability; bank erosion; bank collapse; flood risk; breaching; dredging; liquefaction; submarine landslide; turbidity current; dilatancy

Online: 28 August 2019 (15:17:30 CEST)

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Preprint REVIEW | doi:10.20944/preprints201908.0196.v1

Satellite Remote Sensing of the Greenland Ice Sheet Ablation Zone: A Review

Matthew G. Cooper, Laurence C. Smith

Subject: Earth Sciences, Geophysics Keywords: ablation zone; Greenland; ice sheet; surface mass balance; mass balance; altimetry; albedo; scatterometry; lidar; sea level rise

Online: 20 August 2019 (02:55:39 CEST)

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Preprint REVIEW | doi:10.20944/preprints201908.0018.v1

On Some Properties of the Glacial Isostatic Adjustment Fingerprints

Giorgio Spada, Daniele Melini

Subject: Earth Sciences, Geophysics Keywords: glacial isostatic adjustment; sea level change; fingerprints of past ice melting

Online: 2 August 2019 (08:45:05 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201907.0317.v1

Multiple Scattering Theory for Heterogeneous Elastic Continua with Strong Property Fluctuation: Theoretical Fundamentals and Applications

Huijing He

Subject: Earth Sciences, Geophysics Keywords: scattering; elastic waves; porous materials; dispersion; attenuation; Mohorovičić discontinuity; seismology

Online: 28 July 2019 (15:18:25 CEST)

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Scattering of elastic waves in heterogeneous media has become one of the most important problems in the field of wave propagation due to its broad applications in seismology, natural resource exploration, ultrasonic nondestructive evaluation and biomedical ultrasound. Nevertheless, it is one of the most challenging problems because of the complicated medium inhomogeneity and the complexity of the elastodynamic equations. A widely accepted model for the propagation and scattering of elastic waves, which properly incorporates the multiple scattering phenomenon and the statistical information of the inhomogeneities is still missing. In this work, the author developed a multiple scattering model for heterogeneous elastic continua with strong property fluctuation and obtained the exact solution to the dispersion equation under the first-order smoothing approximation. The model establishes an accurate quantitative relation between the microstructural properties and the coherent wave propagation parameters and can be used for characterization or inversion of microstructures. Starting from the elastodynamic differential equations, a system of integral equation for the Green functions of the heterogeneous medium was developed by using Green’s functions of a homogeneous reference medium. After properly eliminating the singularity of the Green tensor and introducing a new set of renormalized field variables, the original integral equation is reformulated into a system of renormalized integral equations. Dyson’s equation and its first-order smoothing approximation, describing the ensemble averaged response of the heterogeneous system, are then derived with the aid of Feynman’s diagram technique. The dispersion equations for the longitudinal and transverse coherent waves are then obtained by applying Fourier transform to the Dyson equation. The exact solution to the dispersion equations are obtained numerically. To validate the new model, the results for weak-property-fluctuation materials are compared to the predictions given by an improved weak-fluctuation multiple scattering theory. It is shown that the new model is capable of giving a more robust and accurate prediction of the dispersion behavior of weak-property-fluctuation materials. Numerical results further show that the new model is still able to provide accurate results for strong-property-fluctuation materials while the weak-fluctuation model is completely failed. As applications of the new model, dispersion and attenuation curves for coherent waves in the Earth’s lithosphere, the porous and two-phase alloys, and human cortical bone are calculated. Detailed analysis shows the model can capture the major dispersion and attenuation characteristics, such as the longitudinal and transverse wave Q-factors and their ratios, existence of two propagation modes, anomalous negative dispersion, nonlinear attenuation-frequency relation, and even the disappearance of coherent waves. Additionally, it helps gain new insights into a series of longstanding problems, such as the dominant mechanism of seismic attenuation and the existence of the Mohorovičić discontinuity. This work provides a general and accurate theoretical framework for quantitative characterization of microstructures in a broad spectrum of heterogeneous materials and it is anticipated to have vital applications in seismology, ultrasonic nondestructive evaluation and biomedical ultrasound.

Preprint REVIEW | doi:10.20944/preprints201906.0161.v1

On the Main Components of Landscape Evolution Models

Michael Nones

Subject: Earth Sciences, Geophysics Keywords: Numerical modelling; landscape evolution; surface processes; river networks

Online: 17 June 2019 (10:37:13 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201905.0347.v1

On the Restraint Mechanism between the Earth and Moon

Jian Ding

Subject: Earth Sciences, Geophysics Keywords: Moon; Earth; tidal locking; dipole magnetic field; solar wind; moonfall

Online: 29 May 2019 (10:30:43 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201905.0193.v1

Reconstruction of a Segment of the UNESCO World Heritage Hadrian’s Villa Tunnel Network by Integrated GPR, Magnetic-Paleomagnetic, and Electric Resistivity Prospections

Annalisa Ghezzi, Antonio Schettino, Pietro Paolo Pierantoni, Lawrence Conyers, Luca Tassi, Luigi Vigliotti, Erwin Schettino, Milena Melfi, Maria Elena Gorrini, Paolo Boila

Subject: Earth Sciences, Geophysics Keywords: archaeological geophysics; magnetic methods; ground penetrating radar; tunnel detection; data integration

Online: 15 May 2019 (11:14:34 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201905.0052.v1

Coastal Flood Assessment Due to Sea Level Rise and Extreme Storm Events - Case Study of the Atlantic Coast of Portugal Mainland

Carlos Antunes, Carolina Rocha, Cristina Catita

Subject: Earth Sciences, Geophysics Keywords: sea level rise; coastal flood hazard; storm surge; extreme tidal level; GIS

Online: 6 May 2019 (10:57:09 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201904.0249.v1

Methane Hydrate Stability and Potential Reserves in the Levant Basin, Southeastern Mediterranean Sea

Ziv Tayber, Aaron Meilijson, Zvi Ben-Avraham, Yizhaq Makovsky

Subject: Earth Sciences, Geophysics Keywords: gas hydrates, methane stability, seismic interpretation, Levant basin, eastern Mediterranean, climate change

Online: 22 April 2019 (12:06:46 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201904.0081.v1

Estimating Wave Direction by Using Terrestrial GNSS Reflectometry

Jörg Reinking, Ole Roggenbuck, Gilad Even-Tzur

Subject: Earth Sciences, Geophysics Keywords: GNSS; reflectometry; SNR; wave direction

Online: 8 April 2019 (10:41:17 CEST)

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Working Paper REVIEW

The Orson Anderson Era of Mineral Physics at Lamont in the 1960s

Robert Cooper Liebermann

Subject: Earth Sciences, Geophysics Keywords: mineral physics; ultrasonic interferometry; resonant ultrasound spectroscopy; law of corresponding states; equations-of-state; Columbia University; American Geophysical Union

Online: 29 March 2019 (07:54:57 CET)

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Preprint ARTICLE | doi:10.20944/preprints201901.0261.v1

Post-Glacial Land Uplift Rate in Fennoscandia and Laurentia Determined by GRACE Data

Mehdi S. Shafiei Joud, Lars Erik Sjöberg, Mohammad Bagherbandi

Subject: Earth Sciences, Geophysics Keywords: Glacial Isostatic Adjustment; gravimetric land uplift rate modelling; GRACE; independent component analysis

Online: 25 January 2019 (15:08:15 CET)

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Preprint ARTICLE | doi:10.20944/preprints201811.0612.v1

A Deep Temporal Convolutional Neural Network for Regional and Teleseismic Detection

Joshua Dickey, Brett Borghetti, William Junek

Subject: Earth Sciences, Geophysics Keywords: geophysical signal processing; pattern recognition; temporal convolutional neural networks; seismology; deep learning; nuclear treaty monitoring

Online: 29 November 2018 (03:37:48 CET)

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Preprint ARTICLE | doi:10.20944/preprints201811.0361.v1

3D Scattering Imaging of Multiscale Geological Media on the Base of Revised Version of Exploding Reflectors

Evgeny Landa, Galina Reshetova, Vladimir Tcheverda

Subject: Earth Sciences, Geophysics Keywords: Common Middle Point; Propagator; Spatial Reflector; small-scale heterogeneities; diffraction/scattering imaging; finite-difference simulation; local grid refinement in time and space.

Online: 15 November 2018 (11:18:18 CET)

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Preprint ARTICLE | doi:10.20944/preprints201811.0063.v1

Finite Difference Algorithm on Non-uniform Meshes for Modeling 2D Magnetotelluric Responses

Xiaozhong Tong, Yujun Guo, Wei Xie

Subject: Earth Sciences, Geophysics Keywords: finite-difference algorithm; magnetotelluric; 2D structures; modeling

Online: 2 November 2018 (14:03:46 CET)

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Preprint ARTICLE | doi:10.20944/preprints201810.0542.v1

Emergent Scale Invariance and Climate Sensitivity

Rypdal Martin, Hege-Beate Fredriksen, Eirik Myrvoll-Nilsen, Sigrunn H. Sørbye, Kristoffer Rypdal

Subject: Earth Sciences, Geophysics Keywords: Climate sensitivity; scale invariance; long-range persistence; climate variability; emergent constrains

Online: 23 October 2018 (15:59:17 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201810.0356.v2

Surface-Wave Extraction Based on Morphological Diversity of Seismic Events

Xinming Qiu, Chao Wang, Jun Lu, Yun Wang

Subject: Earth Sciences, Geophysics Keywords: higher-mode surface waves; dispersion curves; morphological component analysis; Radon transform

Online: 17 October 2018 (09:00:53 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201810.0356.v1

Surface-Wave Extraction Based on Morphological Diversity of Seismic Events

Xinming Qiu, Chao Wang, Jun Lu, Yun Wang

Subject: Earth Sciences, Geophysics Keywords: higher-mode surface waves; dispersion curves; morphological component analysis; Radon transform

Online: 16 October 2018 (11:31:18 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201810.0337.v1

An Integrated View of Greenland Ice Sheet Mass Changes Based on Models and Satellite Observations

Ruth Mottram, Sebastian B. Simonsen, Synne Høyer Svendsen, Valentina R. Barletta, Louise Sandberg Sørensen, Thomas Nagler, Jan Wuite, Andreas Groh, Martin Horwarth, Job Rosier, Rene Forsberg

Subject: Earth Sciences, Geophysics Keywords: essential climate variables (ECV); climate change initiative (CCI); Greenland ice sheet; mass budget; cryosphere; sea level rise

Online: 16 October 2018 (07:53:22 CEST)

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The Greenland ice sheet is a major contributor to sea level rise, adding an estimated 0.47 +/− 0.23 mm/yr to global mean sea level between 1991 and 2015 (van den Broeke et al., 2016). Making sea level rise projections for the future and understanding the processes controlling current observed rates of sea level rise are crucially dependent on understanding the present-day state of the ice sheet. Here, we provide an overview of the current state of the mass budget of Greenland based on satellite gravimetry and remote sensing observations of surface elevation change, ice sheet velocity and calving front positions. We also combine these essential climate variables with a regional climate model (RCM) output from an ice sheet model (ISM) to gain insight into poorly understood ice sheet dynamical and surface mass processes. On average from 1992 to 2017 the ice sheet in some locations has lost up −2.65 m/yr in elevation based on ESA Radar altimetry analysis. Calving fronts have retreated all around Greenland since the 1990s and in only two out of 28 study locations have they remained stable. The locations of grounding lines at 5 key glaciers with floating ice tongues have remained stable over the observation period. However a detailed case study at Petermann glacier with an ice fracture model shows the sensitivity of these floating ice shelves to future climate change. GRACE gravimetric mass balance (GMB) data allows us to tie together disparate lines of evidence showing that Greenland has lost about 265 +/− 25 Gt/yr of ice over the period 2002 to 2015. RCM and ISM simulations show that surface mass processes dominate the overall Greenland ice sheet mass budget except for areas of fast ice sheet flow but marked differences between models and between models and observations indicate that not all processes are captured accurately, indicating areas of greater uncertainty and directions of future research for future sea level rise projections.

Preprint ARTICLE | doi:10.20944/preprints201810.0107.v1

Probabilistic Substrate Classification with Multispectral Acoustic Backscatter: A Comparison of Discriminative and Generative Models

Daniel Buscombe, Paul Grams

Subject: Earth Sciences, Geophysics Keywords: multibeam echosounder; backscatter; multi-frequency; machine-learning

Online: 5 October 2018 (16:09:53 CEST)

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We propose a probabilistic graphical model for discriminative substrate characterization, to support geological and biological habitat mapping in aquatic environments. The model, called a fully connected conditional random field (CRF), is demonstrated using multispectral and monospectral acoustic backscatter from heterogeneous seafloors in Patricia Bay, British Columbia, and Bedford Basin, Nova Scotia. Unlike previously proposed discriminative machine learning algorithms, the CRF model considers both the relative backscatter magnitudes of different substrates and their relative proximities. The model therefore combines the statistical flexibility of a machine learning algorithm with an inherently spatial treatment of the substrate. The CRF model predicts substrates such that nearby locations with similar backscattering characteristics are likely to be in the same substrate class. The degree of proximity and allowable backscatter similarity are controlled by parameters that are learned from the data. CRF model results were evaluated against a popular generative model known as a Gaussian Mixture model that doesn't include spatial dependencies, only covariance between substrate backscattering response over different frequencies. Both models are used in conjunction with sparse bed observations/samples in a supervised classification. A detailed accuracy assessment, including a leave-one-out cross-validation analysis, was performed using both models. Using multispectral backscatter, the GMM model trained on 50% of the bed observations resulted in a 75% and 89% average accuracies in Patricia Bay and Bedford Basin, respectively. The same metrics for the CRF model were 78% and 95%. Further, the CRF model resulted in a 91% mean cross-validation accuracy across four substrate classes at Patricia Bay, and a 99.5% mean accuracy across three substrate classes at Bedford Basin, which suggest that the CRF model generalizes extremely well to new data. This analysis also showed that the CRF model was much less sensitive to the specific number and locations of bed observations than the generative model, owing to its ability to incorporate spatial autocorrelation in substrates. The CRF approach therefore may prove to be a powerful `spatially aware' alternative to other discriminative classifiers.

Preprint ARTICLE | doi:10.20944/preprints201810.0062.v1

Technical Methodology for ASTER Global Water Body Data Base

Hiroyuki Fujisada, Minoru Urai, Akira Iwasaki

Subject: Earth Sciences, Geophysics Keywords: ASTER instrument, stereo, digital elevation model, global database, optical sensor, water body detection.

Online: 3 October 2018 (17:01:08 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201810.0056.v1

Mass Balance of Novaya Zemlya Archipelago, Russian High Arctic, using Time-Variable Gravity from GRACE and Altimetry Data from ICESat and Cryosat-2

Enrico Ciracì, Isabella Velicogna, Tyler Clark Sutterley

Subject: Earth Sciences, Geophysics Keywords: Novaya Zemlya; Altimetry; Gravity; Russian High Arctic; Glaciers and Ice Caps; Remote Sensing; Climate Change;

Online: 3 October 2018 (14:37:48 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201809.0237.v1

Analysis of Different Statistical Models in Probabilistic Joint Estimation of Porosity and Litho-Fluid Facies from Acoustic Impedance Values

Mattia Aleardi

Subject: Earth Sciences, Geophysics Keywords: reservoir characterization; Bayesian inversion; A-priori statistical models

Online: 13 September 2018 (12:05:12 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201809.0116.v1

Determination of Material Characteristics and Shear Wave Velocity of Volcanic Sediment Layer of Mount Samalas Using MASW Technique

Hiden Hiden, Teguh Ardianto , Suhayat Minardi , Alfina Taurida , Muhajirah Muhajirah

Subject: Earth Sciences, Geophysics Keywords: undifferentiated and wheathered deposits, thin layers, vs characterization, MASW

Online: 6 September 2018 (13:16:56 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201808.0184.v1

High Gas Hydrate and Free Gas Concentrations: An Explanation for Seeps Offshore South Mocha Island

Iván Vargas-Cordero, Umberta Tinivella, Lucía Villar-Muñoz, Joaquim P. Bento

Subject: Earth Sciences, Geophysics Keywords: gas hydrate; BSR; Mocha island; gas-phases

Online: 9 August 2018 (09:46:14 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201807.0584.v1

The Creep-Damage Model of Salt Rock Based on Fractional Derivative

Hongwei Zhou, Di Liu, Gang Lei, Dongjie Xue, Yang Zhao

Subject: Earth Sciences, Geophysics Keywords: salt rock; creep; damage; fractional derivative; acoustic emission

Online: 30 July 2018 (11:15:31 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201806.0466.v1

Analysis of the Spatial and Temporal Distribution of the 2011 Earthquakes in Lake Van Area and Rupture Complexity of the Aftershock Sequence in Eastern Anatolia, Turkey

Mustafa Toker

Subject: Earth Sciences, Geophysics Keywords: Lake Van; Van earthquake; aftershock hypocenters; rupture complexity; azimuthal distribution; aftershock clusters; microseismicity

Online: 28 June 2018 (11:26:31 CEST)

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This study presents an analysis of the spatial and temporal distribution of the two large destructive earthquakes that occurred in Lake Van area on October 23, and November 9, 2011, together with the azimuth-dependent distribution of the seismic activity and microseismicity clusters after the mainshocks, associated with the complex rupture processes of their aftershock sequence. The sequence began with the magnitude Mw 7.1 earthquake of 23 October and a second destructive earthquake of Mw 5.6. The aftershock sequences of the two mainshocks were linked to the local crustal faults beneath Lake Van area, followed successively and produced unusually intense activity and significant damage in the area. The main purposes of this study are to document the spatial and temporal distribution and evolution of the October 23, 2011 aftershock hypocenters and the azimuth-dependent distribution of seismic activity, and to understand the spatial and temporal character of the aftershock sequence using the distributional and evolutional patterns of the aftershock hypocenters. A total of 10,000 aftershocks were obtained from seismic data with a high signal-to-noise ratio over collected over three years from October 23, 2011 to March 2014. These aftershocks were plotted for the time periods from November 2011 through March 2012 to March 2014 and ≈ 5000 aftershocks were retained in the depth versus distance cross-sections to detect the clusters in the first step of study (November 2011–March 2012). The focal depth distribution of the aftershock clusters, the migration of hypocenter activity and microseismicity clusters were analyzed and the distributional patterns of the detected clusters were assessed using the geometric distribution of the aftershock hypocenters. The spatial and temporal distribution of aftershocks reveal interesting key features of the deep rupture complexity of the Van earthquake: (1) most prominent aftershocks have been located in the upper crust at depths shallower than 10 km beneath ruptured area, indicating that the upper crust is brittle and seismogenic; (2) two spatial clusters have been detected at 8-10 km depths and the upward extrapolation of these clusters intersects with faults; the main cluster (60 km wide) bounded by inferred reverse faults (f3 and f4) and the central cluster (25–30 km wide) bounded by faults (f1 and f2); (3) these spatial clusters form the largest volumetric pattern of the conical-shaped cluster at depths of about 25–30 km of the azimuth-dependent rotational projections, suggesting azimuthal distributions of deep rupture characteristics; and (4) the strongest temporal cluster of microseismicity derived from temporal distribution of aftershocks has been detected within an area of about 2.5–3.0 km² and it is spatially observed at 20 km depth within the central cluster, suggesting progressive failure of the adjacent patches of possible fault.

Preprint ARTICLE | doi:10.20944/preprints201806.0414.v1

The Development of Cartographical Studies and Praxis in Montenegro

Gojko Nikolic, Velibor Spalevic, Zoran Susic, Mehmed Batilovic, Goran Skataric, Ruzica Bozovic, Radovan Djurovic, Dragan Vuckovic

Subject: Earth Sciences, Geophysics Keywords: Montenegro; cadastre; geography; geodesy; geoinformatics; syllabus for cartography; cartographical heritage

Online: 26 June 2018 (12:07:05 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201806.0408.v1

Land Surface Albedo Derived on a Ten Daily Basis from Meteosat Second Generation Observations: the NRT and Climate Data Record Collections from the EUMETSAT LSA SAF

Dominique Carrer, Suman Moparthy, Gabriel Lellouch, Xavier Ceamanos, Florian Pinault, Sandra Coelho, Isabel Trigo

Subject: Earth Sciences, Geophysics Keywords: surface albedo; remote sensing; geostationary satellites; climate data records; essential climate variables; near real-time; operational processing; climate; land surface modeling

Online: 26 June 2018 (10:31:10 CEST)

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Land surface albedo determines the splitting of downwelling solar radiation into components which are either reflected back to the atmosphere or absorbed by the surface. Land surface albedo is an important variable for the climate community and therefore was defined by the Global Climate Observing System (GCOS) as an Essential Climate Variable (ECV). Within the scope of the Satellite Application Facility for Land Surface Analysis (LSA SAF) of EUMETSAT, a near-real time (NRT) daily albedo product was developed in the last decade from observations provided by the SEVIRI instrument on board the geostationary satellites of the Meteosat Second Generation (MSG) series. In this study we present a new collection of albedo satellite products based on the same satellite data. The MSG Ten-day ALbedo (MTAL) product incorporates MSG observations over 31 days with a frequency of NRT production of 10 days. The MTAL collection is more dedicated to climate analysis studies compared to the daily albedo that was initially designed for the weather prediction community. For this reason, a homogeneous reprocessing of MTAL was done in 2018 to generate a Climate Data Record (CDR). The resulting product is called MTAL-R and has been made available to the community in addition to the NRT version of the MTAL product which has been available for several years. The retrieval algorithm behind the MTAL products comprises three distinct modules: one for atmospheric correction, one for daily inversion of a semi-empirical model of the bidirectional reflectance distribution function, and one for monthly composition that also determines surface albedo values. In this study the MTAL-R CDR is compared to ground surface measurements and concomitant albedo products collected by sensors on-board polar-orbiting satellites (SPOT-VGT and MODIS). We show that MTAL-R meets the quality requirements if MODIS or SPOT-VGT are considered as reference. This work leads to 14 years of production of geostationary land surface albedo products with a guaranteed continuity in the LSA SAF for the future years with the forthcoming third generation of European geostationary satellites.

Preprint ARTICLE | doi:10.20944/preprints201806.0224.v1

Time-Series Displacement of Landslide In Danba County (China) Monitoried By the Small Baseline Subset (SBAS) Technique

Bo Hu, Yang Wu

Subject: Earth Sciences, Geophysics Keywords: SBAS; landslide; danba; time-series; displacement

Online: 14 June 2018 (08:44:11 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201806.0006.v1

Radar Data Analyses for a Single Rainfall Event and Their Application for Flow Simulation in an Urban Catchment Using the SWMM Model

Mariusz Barszcz

Subject: Earth Sciences, Geophysics Keywords: urban catchment; radar reflectivity; rainfall rate; Z-R relationship; SWMM model; flow simulation

Online: 1 June 2018 (07:46:00 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201805.0372.v1

The Life and Death of the Hiatus Consistently Explained

Kristoffer Rypdal

Subject: Earth Sciences, Geophysics Keywords: hiatus; attribution; volcanic forcing; solar forcing; anthropogenic forcing; AMO; ENSO; multiple regression; long-memory response

Online: 25 May 2018 (14:49:51 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201805.0277.v1

Temperature and Conductivity as Indicators of the Morphology and Activity of a Submarine Volcano: Avyssos (Nisyros) in the South Aegean Sea, Greece

Evangelos Bakalis, Theo J. Mertzimekis, Paraskevi Nomikou, Francesco Zerbetto

Subject: Earth Sciences, Geophysics Keywords: Generalized Moments Method; time series; submarine volcano; Nisyros

Online: 22 May 2018 (11:09:41 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201805.0132.v1

Statistical Analysis of Tropical Cyclones in the Solomon Islands

Edward Maru, Taiga Shibata, Kosuke Ito

Subject: Earth Sciences, Geophysics

Online: 8 May 2018 (15:34:08 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201804.0208.v1

A Quantitative Prediction Method for Fracture Density Based on the Equivalent Medium Theory

Liang Sun, Suping Peng, Dengke He, Shu Wang

Subject: Earth Sciences, Geophysics Keywords: fracture density; double-layer model; unconventional reservoirs; multicomponent seismic; shear-wave splitting

Online: 16 April 2018 (11:33:54 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201801.0026.v1

Basin Resonance and Seismic Hazard for Jakarta, Indonesia

Athanasius Cipta, Phil Cummins, Masyhur Irsyam, Sri Hidayati

Subject: Earth Sciences, Geophysics Keywords: seismic hazard; openquake; GMPE; basin-induced amplification; SPECFEM2D

Online: 4 January 2018 (10:04:35 CET)

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Preprint ARTICLE | doi:10.20944/preprints201710.0148.v1

A Controlled-Site Comparison of Microwave Tomography and Time-Reversal Imaging Techniques for GPR Surveys

Vinicius Santos, Emerson Almeida, Jorge Porsani, Fernando Teixeira, Francesco Soldovieri

Subject: Earth Sciences, Geophysics Keywords: ground penetrating radar; microwave tomography; time-reversal technique

Online: 23 October 2017 (11:08:34 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201709.0079.v1

Calibrating the EGS Flow Stimulation Process for Basement Rock

Peter Leary, Peter Malin, Tero Saarno, Ilmo Kukkonen

Subject: Earth Sciences, Geophysics Keywords: EGS; crustal permeability; finite element flow modelling; crustal wellbore temperatures; wellbore injection; well logs; well core

Online: 18 September 2017 (12:01:16 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201704.0081.v1

Subduction Zone Characterization of the Northern Papua through the Study of Earthquake History

Miftachul Janah, Supriyadi Supriyadi, Ian Yulianti, Yuni Trisnowati, Andya S. P. Putro

Subject: Earth Sciences, Geophysics Keywords: Northern Papua; Subduction; Seismicity

Online: 14 April 2017 (05:55:31 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201702.0092.v2

Variability of Darcian Flux in the Hyporheic Zone at a Natural Channel Bend

Shaofeng Xu, Jinxi Song, Weiwei Jiang, Guotao Zhang, Ming Wen, Junlong Zhang, Ying Xue

Subject: Earth Sciences, Geophysics Keywords: hyporheic zone; Darcian flux; channel bend; vertical hydraulic conductivity; stream topography; grain size; porosity

Online: 26 February 2017 (10:07:31 CET)

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Preprint ARTICLE | doi:10.20944/preprints201611.0029.v1

Categorical Forecast of Precipitation Anomaly Using the Standardized Precipitation Index SPI

Leszek Łabędzki

Subject: Earth Sciences, Geophysics Keywords: precipitation deficit; precipitation surplus; standardized precipitation index SPI; forecast; verification

Online: 4 November 2016 (13:39:29 CET)

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Preprint ARTICLE | doi:10.20944/preprints201610.0062.v1

Crustal and Upper Mantle Density Structure Beneath the Qinghai-Tibet Plateau and Its Surrounding Areas Derived from EGM2008 Geoid Anomalies

Honglei Li, Jian Fang

Subject: Earth Sciences, Geophysics Keywords: Qinghai-Tibet Plateau; geoid anomaly inversion; crustal and upper mantle density construction

Online: 15 October 2016 (08:25:13 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201610.0023.v1

Hydrological Implications of Climate Change on River Basin Water Cycle: Case Studies of the Yangtze River and Yellow River Basins, China

Liu Liu, Zongxue Xu, Rong Li, Youzhi Wang

Subject: Earth Sciences, Geophysics Keywords: climate change; water cycle; downscaling; hydrological model; Yangtze River; Yellow River; Tibetan Plateau

Online: 8 October 2016 (11:29:05 CEST)

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Preprint ARTICLE | doi:10.20944/preprints201607.0066.v1

MERIDIONAL AND ZONAL WAVENUMBER DEPENDENCE IN POTENTIAL VORTICITY FLUX IN ROSSBY WAVES

Sanjeeva Balasuriya

Subject: Earth Sciences, Geophysics Keywords: maximum flux; midlatitude cyclones; oceanic jets; chaotic transport

Online: 22 July 2016 (05:17:29 CEST)

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