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We image the lateral variations in the Moho depths and average crustal composition across the Kumaon-Garhwal (KG) Himalaya, through the H-K stacking of 1400 radial PRFs from 42 three-component broadband stations. The modelled Moho depth, average crustal Vp/Vs, and Poisson's ratio estimates vary from 28.3 to 52.9 km, 1.59 to 2.13 and 0.17 to 0.36, respectively, in the KG Himalaya. We map three NS to NNE trending transverse zones of significant thinning of mafic crust, which are interspaced by zones of thickening of felsic crust. These mapped transverse zones bend toward the north to form a NE dipping zone of maximum changes in Moho depths, below the region between Munsiari and Vaikrita thrusts. The 1991 M6.6 Uttarakashi and 1999 M6.4 Chamoli earthquakes have occurred on the main Himalayan thrust (MHT), lying just above the mapped zone of maximum changes in Moho depths. Modelled large values of average crustal Vp/Vs (> 1.85) could be attributed to the high fluid (metamorphic fluids) pressure associated with the mid-crustal MHT. Additionally, the serpentinization of the lowermost crust resulted from the continent-continent Himalayan collision process could also contribute to the increase of the average crustal Vp/Vs ratio in the region.
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http://dx.doi.org/10.1038/s41598-021-93469-1 | DOI Listing |
Sci Rep
July 2025
Department of Earth Sciences, University of Adelaide, Adelaide, Australia.
Central Australia preserves a record of micro-continent and craton accretion during assembly of the Paleoproterozoic Nuna supercontinent 2500 - 1600 Ma, followed by Mesoproterozoic magmatic and orogenic events that formed the Musgrave Province. The Petermann Orogeny (630 - 520 Ma) and Alice Springs Orogeny (450 - 300 Ma) resulted in north-south crustal shortening and Moho offsets up to 20 km that yield gravity variations of ~ 160 mGals. Three-dimensional inversion of 614 long-period (10-10000 s) AusLAMP MT and 36 geomagnetic depth sounding (GDS) sites spaced ~ 55 km produced resistivity estimates to 250 km depth, covering 1500 km west-east, 1300 km north-south.
View Article and Find Full Text PDFACS Omega
June 2025
School of Energy Resources, China University of Geosciences (Beijing), 29 Xueyuan Road, Beijing 100083, China.
Reservoir temperature is a critical factor influencing the formation and production of coal, coalbed methane (CBM), and geothermal heat flow (GHF), with GHF serving as a key indicator of subsurface thermal conditions. In this study, an extreme gradient boosting (XGB) model is developed to predict GHF in China using 12 geological and geophysical features. The model is trained on both global and China-specific data sets and evaluated using MAE, RMSE, and metrics.
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May 2025
Dipartimento di Scienze della Terra e del Mare, Università di Palermo, Palermo, Italy.
A detailed Moho map is essential for understanding the deep structure of a given area, especially for a complex area such as the Sicily Channel, shaped by the Europa-Africa convergence. We built a new Moho map of the central-western Sicily Channel using a multidisciplinary approach, which comprises the analysis of crustal seismic reflection profiles and velocity models from multiple databases. We found two earthquake alignments that occurred in the study area from 1981 to the present that reach sub-Moho depths and through which we constructed two lithospheric seismogenic volumes (LSVs).
View Article and Find Full Text PDFSensors (Basel)
February 2025
School of Electric & Electronic Engineering, Wuhan Polytechnic University, Wuhan 430023, China.
The geological structure in the Red River fault zone (RRF) and adjacent areas is complex. Due to the lack of high-precision gravity data in the study area, it is difficult to obtain the distribution of materials within the Earth's crust. In this study, a gravity data-fused method is proposed.
View Article and Find Full Text PDFHeliyon
January 2025
Department of Physics, College of Natural and Computational Sciences, Debre Tabor University, P.O.Box 272, Debre Tabor, Ethiopia.
The northwest Ethiopian plateau is one of the globe's most complex tectonic zones. Within the area, the previous geological and geophysical investigations revealed volcanism and deformation effects but did not thoroughly examine crust movement, isostatic compensation, and deformation patterns. The main focus of this study is to use high-resolution topography and gravity data to map the region's vertical tectonic stress and crustal thickness, including isostatic and gravity Moho, in order to obtain a better understanding of the tectonics of the area.
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