The Kale-Yeşilyurt Fault Zone(KYFZ)exhibits recent tectonic reactivation,which is critical for understanding regional seismicity and the geodynamic evolution of the East Anatolian Fault System(EAFS).This study integra...The Kale-Yeşilyurt Fault Zone(KYFZ)exhibits recent tectonic reactivation,which is critical for understanding regional seismicity and the geodynamic evolution of the East Anatolian Fault System(EAFS).This study integrates kinematic and morphometric analyses to explore the reactivation processes along the fault.Kinematic analysis,incorporating fault-slip data and stress inversion,reveals complex deformation patterns characterized by strike-slip and extensional movements,with NE-SW trending minimum stress axes.February 6,2023,earthquake sequence highlighted significant stress accumulation along the Kale-Yeşilyurt and Göksun segments.Fieldwork and morphometric analyses,including mountain front sinuosity(Smf)and drainage basin analysis,suggest variable uplift rates and tectonic forces,with an asymmetric westward-directed uplift along the KYFZ.HI-HC index analysis underscores rapid uplift,particularly in the western basin,signaling ongoing tectonic and geomorphic activity.The normalized channel steepness index(Ksn)values reveal variations in erosion rates,providing insight into regional uplift patterns and knickpoint distribution.While morphometric indicators collectively point to high tectonic activity along the Yeşilyurt segment,the Kale segment exhibits particularly intense activity with a dominant normal fault component.The 2020 Sivrice earthquake and the 2023 earthquake doublet further emphasize the structural complexity of the fault system and underscore the KYFZ’s pivotal role in the active tectonics of the EAFS.Future research incorporating advanced geospatial technologies is vital for improving our understanding of tectonic processes,mitigating earthquake hazards,and enhancing seismic risk assessments.展开更多
The Gulf of Mannar has been producing natural gas in the Sri Lankan portion.This indicates that a detail geoscientific study is to be undertaken from the Indian section of the gulf,which can have a far-reaching implic...The Gulf of Mannar has been producing natural gas in the Sri Lankan portion.This indicates that a detail geoscientific study is to be undertaken from the Indian section of the gulf,which can have a far-reaching implication in the Indian petroleum geoscience.In this work,morphometric and gravity studies were made from the gulf/basin near the onshore area,and bathymetric studies from the offshore portion of the Mannar basin within the Indian sector.Five watersheds were delineated based on study of eight geomorphic parameters on remote sensing images form the onshore area.Out of these watersheds 4 and5 are found to be presently tectonically most active.Well-bore stability issue is to be considered while drilling these portions in future.We further prepared a regional contour map for the offshore study area,analysed the free air gravity data from the onshore area,and deduced the First Vertical Derivative(FVD)and Tilt Derivative Ratio(TDR).Bathymetric height gradually increases along the north-south trend from the coast region of the study area towards the central region,while the gravity magnitudes display a very sharp gradient(around 150 mGal).The gravity anomaly shows positive values at continental shelf(0-160 mGal),which includes parts of watersheds 1 and 3 and attains negative magnitude(up to-20mGal)towards the basin area.Negative gravity anomaly in the offshore area may indicate presence of hydrocarbon but more studies are needed for confirmation.Apparently,almost a negative correlation(except watershed 1)between surface elevation and free air gravity magnitudes has been found.展开更多
文摘The Kale-Yeşilyurt Fault Zone(KYFZ)exhibits recent tectonic reactivation,which is critical for understanding regional seismicity and the geodynamic evolution of the East Anatolian Fault System(EAFS).This study integrates kinematic and morphometric analyses to explore the reactivation processes along the fault.Kinematic analysis,incorporating fault-slip data and stress inversion,reveals complex deformation patterns characterized by strike-slip and extensional movements,with NE-SW trending minimum stress axes.February 6,2023,earthquake sequence highlighted significant stress accumulation along the Kale-Yeşilyurt and Göksun segments.Fieldwork and morphometric analyses,including mountain front sinuosity(Smf)and drainage basin analysis,suggest variable uplift rates and tectonic forces,with an asymmetric westward-directed uplift along the KYFZ.HI-HC index analysis underscores rapid uplift,particularly in the western basin,signaling ongoing tectonic and geomorphic activity.The normalized channel steepness index(Ksn)values reveal variations in erosion rates,providing insight into regional uplift patterns and knickpoint distribution.While morphometric indicators collectively point to high tectonic activity along the Yeşilyurt segment,the Kale segment exhibits particularly intense activity with a dominant normal fault component.The 2020 Sivrice earthquake and the 2023 earthquake doublet further emphasize the structural complexity of the fault system and underscore the KYFZ’s pivotal role in the active tectonics of the EAFS.Future research incorporating advanced geospatial technologies is vital for improving our understanding of tectonic processes,mitigating earthquake hazards,and enhancing seismic risk assessments.
文摘The Gulf of Mannar has been producing natural gas in the Sri Lankan portion.This indicates that a detail geoscientific study is to be undertaken from the Indian section of the gulf,which can have a far-reaching implication in the Indian petroleum geoscience.In this work,morphometric and gravity studies were made from the gulf/basin near the onshore area,and bathymetric studies from the offshore portion of the Mannar basin within the Indian sector.Five watersheds were delineated based on study of eight geomorphic parameters on remote sensing images form the onshore area.Out of these watersheds 4 and5 are found to be presently tectonically most active.Well-bore stability issue is to be considered while drilling these portions in future.We further prepared a regional contour map for the offshore study area,analysed the free air gravity data from the onshore area,and deduced the First Vertical Derivative(FVD)and Tilt Derivative Ratio(TDR).Bathymetric height gradually increases along the north-south trend from the coast region of the study area towards the central region,while the gravity magnitudes display a very sharp gradient(around 150 mGal).The gravity anomaly shows positive values at continental shelf(0-160 mGal),which includes parts of watersheds 1 and 3 and attains negative magnitude(up to-20mGal)towards the basin area.Negative gravity anomaly in the offshore area may indicate presence of hydrocarbon but more studies are needed for confirmation.Apparently,almost a negative correlation(except watershed 1)between surface elevation and free air gravity magnitudes has been found.
