REVIEW | doi:10.20944/preprints202204.0226.v2
Subject: Environmental And Earth Sciences, Geophysics And Geology Keywords: paleomagnetic mapping; paleomagnetic profiling; radiometric dating; tectonic-structural interpretation; integrated study
Online: 5 May 2022 (05:00:57 CEST)
The easternmost Mediterranean is a distinct transition zone from the ocean to the continent located at the junction between the largest Earth's lithospheric segments: Eurasian and African. The methodology of paleomagnetic mapping of such transition zones is based on integrating the mapping techniques for both continental and oceanic platforms: paleomagnetic reconstructions, results of radiometric dating of magnetized rocks, tectonic-structural reconstructions, biogeography, and utilization of the results of various geophysical surveys. The geodynamic-paleomagnetic mapping makes it possible to reveal the multilevel structural heterogeneity and display complex elements of the geodynamics of different ages inherent in this transition zone. Northern Israel is obviously the most complex area in the easternmost Mediterranean. For the combined paleomagnetic mapping, well-studied paleomagnetically and radiometrically areas were selected: (1) the Carmel area, (2) the Atlit area (internal part of the Carmel area), (3) the Sea of Galilee with the adjoining zones (primarily, the Kinnarot Valley), and (4) the area of the Hula Basin with adjacent areas of the Golan Plateau, Hermon Mt., and Galilea uplift. The constructed paleomagnetic profiles for the Carmel area (on the top of the accumulative surface of the Lower Cretaceous traps), and the Kinnarot Valley – Sea of Galilee – Hula Basin, evidently indicate the complex history of the paleogeodynamic evolution of the region. These studies demonstrate the effectiveness of paleomagnetic mapping integrated with paleomagnetic profiling, crossing these geologically complex areas.
REVIEW | doi:10.20944/preprints202308.1252.v1
Subject: Environmental And Earth Sciences, Geophysics And Geology Keywords: geodynamics; Turkish February 2023 earthquakes; rotating mantle structure; GPS; gravity; magnetic; and paleomagnetic data analysis
Online: 17 August 2023 (05:33:13 CEST)
The Easternmost Mediterranean is a junction zone between the largest Earth's lithospheric segments – Eurasian and African-Arabian, and a transition area from the ocean to the continent. The latest catastrophic earthquakes in eastern Turkey require their geodynamic understanding. The two most decisive events (with magnitude (M) = 7.8 and 7.7) were observed with an interval of 9 hours on February 06, 2023, followed by a whole series of about 10,000 significative aftershocks. These tragic events led to the death of more than 60 thousand people. The above values indicate the colossal tension created in the Earth's crust. The region where these strongest earthquakes occurred is a tectonically very complex junction zone of four tectonic plates: Eurasian, Arabian, African, and Anatolian. The joint movement of these plates (consisting, in turn, of tectonic elements of different ages) occurs at an average rate of 6–15 mm per year. However, after two marked powerful shocks and a series of aftershocks, some sectors of the Anatolian plate shifted to the southwest by more than 11 meters. What happened in eastern Turkey? The interaction of numerous factors complicates the tectonic–geodynamic characteristics of the region. Let us analyze what is the most influencing component. Our recent publications (Eppelbaum et al., 2020, 2021) indicated the presence of a giant, rotating quasi-ring structure below the Easternmost Mediterranean. The GPS vector map coinciding with the gravitational trend displays the counterclockwise rotation of this structure. A review of paleomagnetic data on the projection of the discovered structure into the Earth's surface confirms its mainly counterclockwise rotation. Analysis of the magnetic field ΔZ, geoid anomalies map, and seismic tomography data commonly prove the presence of this deep anomaly. The geodynamic and structural characteristics of the region and paleobiogeographic data are consistent with the proposed physical–geological model. A widespread analysis of tectonic, petrological, and mineralogical data implies a connection between the discovered deep structure and near-surface processes. An examination of numerous publications by different authors confirms the above phenomenon’s existence. A crucial for understanding the nature of the considered seismic stress is its location near the expressed bend of the Mesozoic terrane belt, where the Arabian Plate is deeply intruded into the Alpine-Himalayan belt. Thus, the rotation of this giant deep structure may accumulate the stress effect and be one of the causative reasons for the last catastrophic geodynamic events in Eastern Turkey.
REVIEW | doi:10.20944/preprints202112.0015.v1
Subject: Environmental And Earth Sciences, Geophysics And Geology Keywords: Hydrospheric events; tectonic-geodynamic zonation; paleogeographic reconstructions; ancient man migration; Levantine Corridor; paleomagnetic correlation; deep geodynamic factors
Online: 1 December 2021 (13:06:47 CET)
The origin of the man at the Earth is directly associated with the determination of directions of the flow distribution of the ancient man migration to adjacent territories. In such studies traditionally mainly landscape and climatological changes are considered. We suggest that along with the above factors, regional tectonic-geodynamic factors played a dominant role in the character of migration. The considered African-Levantine-Caucasian region is one of the most complex regions of the world, where collisional and spreading processes of geodynamics converge. First is determined an essential influence of the Akchagylian hydrospheric maximum (about 200 m above the mean sea level) limiting the ancient men migration from Africa to Eurasia. We propose that the Levantine Corridor emerged after the end of the Akchagylian transgression and landscape forming in the Eastern Mediterranean. This corridor location was formed by the movements between the Dead Sea Transform and the boundary of the carbonate platform of the Mesozoic Terrane Belt. Further landscape evolution was largely determined by the geodynamic behavior of the deep mantle rotating structure occurring below the central part of the region under study. All the mentioned events around and in the Levantine Corridor have been studied in detail on the basis of the combined geodynamic, paleogeographic, and paleomagnetic analyzes performed in northern Israel (Carmel uplift and Galilee plateau). Careful studies of the Evron quarry geological section indicate that it is a unique one for the dating of the marine and continental archaeological sequences and sheds light on the movement of the ancient man along the Levantine Corridor.