ARTICLE | doi:10.20944/preprints201804.0208.v1
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)
Fracture density, a critical parameter of unconventional reservoirs, can be used to evaluate potential of unconventional reservoirs and location of production wells. Many technologies, such as amplitude variation with offset and azimuth (AVOA) technology, vertical seismic profiling (VSP) technology, and multicomponent seismic technology, are generally used to predict fracture of reservoirs. they can qualitatively predict fracture by analyzing seismic attributes, including seismic wave amplitudes, seismic wave velocities, which are sensitive to fracture. However, it is important to quantitatively describe fracture of reservoirs. In this study, based on a double-layer model, the relationships between fracture density and the double-layer model’s physical parameters, such as velocity of fast shear-wave, velocity of slow shear-wave, and density, were established, and then a powerful quantitative prediction method for fracture density was proposed dramatically. Afterwards, the Hudson model for crack was used to test the applicability of the method. The result shown that the quantitative prediction method for fracture density can be applied suitable to the Hudson model for crack. Finally, the result of validation models indicated that the method can predict fracture density effective, in which absolute relative deviation (ARD) were less than 5% and root-mean-square error (RMSE) was 4.88×10-3.
ARTICLE | doi:10.20944/preprints201802.0075.v1
Subject: Biology, Plant Sciences Keywords: OsCd1; Cadmium accumulation; rice grain; indica; japonica; GWAS
Online: 9 February 2018 (07:13:17 CET)
Cadmium accumulation in rice grain poses a serious threat to people’s health. Understanding the genetic basis on grain cadmium accumulation facilitates efforts to reduce it. Here, we show that OsCd1 is involved in Cd uptake and contributes to grain accumulation in rice. Natural variation in OsCd1 with a missense mutation Val449Asp is responsible for the divergence of rice grain cadmium accumulation between japonica and indica. Notably, near-isogenic line tests confirmed that the indica variety carrying the OsCd1V449 allele could reduce the grain cadmium accumulation. The favorable allele OsCd1V449 may be an important genetic resource to reduce grain cadmium accumulation for indica.