Through field geologic survey,fine interpretation of seismic reflection data and analysis of well drilling data,the differential deformation,tectonic transfer and controlling factors of the differential deformation of...Through field geologic survey,fine interpretation of seismic reflection data and analysis of well drilling data,the differential deformation,tectonic transfer and controlling factors of the differential deformation of the Gumubiezi Fault(GF)from east to west have been studied systematically.The study shows that GF started to move southward as a compressive decollement along the Miocene gypsum-bearing mudstone layer in the Jidike Formation at the Early Quaternary and thrust out of the ground surface at the northern margin of the Wensu Uplift,and the Gumubiezi anticline formed on the hanging wall of the GF.The displacement of the GF decreases gradually from 1.21 km in the east AA′transect to 0.39 km in the west CC′transect,and completely disappears in the west of the Gumubiezi anticline.One part of the displacement of the GF is converted into the forward thrust,and another part is absorbed by Gumubiezi anticline.The formation of the GF is related to the gypsum-bearing mudstone layer in the Jidike Formation and barrier of the Wensu Uplift.The differential deformation of the GF from east to west is controlled by the development difference of gypsum-bearing mudstone layer in the Jidike Formation.In the east part,gypsum-bearing mudstone layer in the Jidike Formation is thicker,the deformation of the duplex structure in the north of the profile transferred to the basin along gypsum-bearing mudstone layer;to the west of the Gumubiezi structural belt(GSB),the gypsum-bearing mudstone layer in Jidike Formation decreases in thickness,and the transfer quantity of deformation of the duplex structure along the gypsum-bearing mudstone layer to the basin gradually reduces.In contrast,on the west DD′profile,the gypsum-bearing mudstone is not developed,the deformation of the deep duplex structure cannot be transferred along the Jidike Formation into the basin,the deep thrust fault broke to the surface and the GF disappeared completely.The displacement of the GF to the west eventually disappeared,because the lateral ramp acts as the transitional fault between east and west part of GSB.展开更多
Understanding the scaling relation of damage zone width with displacement of faults is important for predicting subsurface faulting mechanisms and fluid flow processes. The understanding of this scaling relationship i...Understanding the scaling relation of damage zone width with displacement of faults is important for predicting subsurface faulting mechanisms and fluid flow processes. The understanding of this scaling relationship is influenced by the accuracy of the methods and types of data utilized to investigate faults. In this study, seismic reflection data are used to investigate the throw and damage zone width of five strike-slip faults a ecting Ordovician carbonates of the Tarim intracraton basin,NW China. The results indicate that fault slips with a throw less than 200 m had formed wide damage zones up to 3000 m in width. Also, damage zone width is found to have both a positive correlation and a power-law relation with throw of two orders of magnitude, with a ratio of these values varying in a range of 2–15. The relationship between throw and damage zone width is not a simple power-law and changes its slope from small to larger size faults. The results indicate that throw scales well with damage zone width for the studied faults, and hence these can be used to predict fault geometries in the Tarim Basin. The study of the wide carbonate damage zones presented here provides new insights into scaling of large-size faults, which involve multiple faulting stages.展开更多
The Bachu （巴楚） uplift is one of the most active tectonic regions nowadays in the Tarim basin, which is also a faulted block uplift that was intensively active during the Cenozoic. This study was based primarily on...The Bachu （巴楚） uplift is one of the most active tectonic regions nowadays in the Tarim basin, which is also a faulted block uplift that was intensively active during the Cenozoic. This study was based primarily on the geological structure interpretation of seismic profiles, applying the theories and methods of basin dynamics, structural analysis and tectono-stratigraphic analysis, the geometry and kinematics features of the fault systems in the Bachn uplift were analyzed in detail. Our study shows that each fault belt is mainly characterized by compression and overthrusting, most of the faults initiated and activated during the Mid-Late Himalayan period, and that the general structural styles of the Bachu uplift were basement-involved pop-up thrust faulted block uplift, of which the southern margin was covered by the large-scale decollement fault system. The basement-involved structures widely developed in the higher position of the basement uplift, while decollement fault system developed mainly at the position with gypsum mudstone. The evolution process of Bachu uplift included back-bulge slope of the peripheral foreland basin in Mid-Late Caledonian, forebulge in HercynianYanshanian and the latest compressional faulted block uplift in Mid-Late Himalayan. Meanwhile,the study also suggests that the formation, reconstruction and stabilization of the uplift were controlled by the development and evolution of fault systems clearly. In the early forebulge stage, it was mainly presented as flexural deformation without the developing of thrust faults in the Bachu area; to the late stage, under the influence of violent lateral compression deformation, the faulted block uplift formed finally.展开更多
基金Supported by the China National Science and Technology Major Project(2017ZX05008001,2016ZX05003001)
文摘Through field geologic survey,fine interpretation of seismic reflection data and analysis of well drilling data,the differential deformation,tectonic transfer and controlling factors of the differential deformation of the Gumubiezi Fault(GF)from east to west have been studied systematically.The study shows that GF started to move southward as a compressive decollement along the Miocene gypsum-bearing mudstone layer in the Jidike Formation at the Early Quaternary and thrust out of the ground surface at the northern margin of the Wensu Uplift,and the Gumubiezi anticline formed on the hanging wall of the GF.The displacement of the GF decreases gradually from 1.21 km in the east AA′transect to 0.39 km in the west CC′transect,and completely disappears in the west of the Gumubiezi anticline.One part of the displacement of the GF is converted into the forward thrust,and another part is absorbed by Gumubiezi anticline.The formation of the GF is related to the gypsum-bearing mudstone layer in the Jidike Formation and barrier of the Wensu Uplift.The differential deformation of the GF from east to west is controlled by the development difference of gypsum-bearing mudstone layer in the Jidike Formation.In the east part,gypsum-bearing mudstone layer in the Jidike Formation is thicker,the deformation of the duplex structure in the north of the profile transferred to the basin along gypsum-bearing mudstone layer;to the west of the Gumubiezi structural belt(GSB),the gypsum-bearing mudstone layer in Jidike Formation decreases in thickness,and the transfer quantity of deformation of the duplex structure along the gypsum-bearing mudstone layer to the basin gradually reduces.In contrast,on the west DD′profile,the gypsum-bearing mudstone is not developed,the deformation of the deep duplex structure cannot be transferred along the Jidike Formation into the basin,the deep thrust fault broke to the surface and the GF disappeared completely.The displacement of the GF to the west eventually disappeared,because the lateral ramp acts as the transitional fault between east and west part of GSB.
基金partly supported by National Natural Science Foundation of China(Grant No.41472103)Technology Major Project(2016ZX05004001)
文摘Understanding the scaling relation of damage zone width with displacement of faults is important for predicting subsurface faulting mechanisms and fluid flow processes. The understanding of this scaling relationship is influenced by the accuracy of the methods and types of data utilized to investigate faults. In this study, seismic reflection data are used to investigate the throw and damage zone width of five strike-slip faults a ecting Ordovician carbonates of the Tarim intracraton basin,NW China. The results indicate that fault slips with a throw less than 200 m had formed wide damage zones up to 3000 m in width. Also, damage zone width is found to have both a positive correlation and a power-law relation with throw of two orders of magnitude, with a ratio of these values varying in a range of 2–15. The relationship between throw and damage zone width is not a simple power-law and changes its slope from small to larger size faults. The results indicate that throw scales well with damage zone width for the studied faults, and hence these can be used to predict fault geometries in the Tarim Basin. The study of the wide carbonate damage zones presented here provides new insights into scaling of large-size faults, which involve multiple faulting stages.
基金supported by the National Science and Technology Major Project (No. 2011ZX05009-001)the National Natural Science Foundation of China (No. 41102071)
文摘The Bachu （巴楚） uplift is one of the most active tectonic regions nowadays in the Tarim basin, which is also a faulted block uplift that was intensively active during the Cenozoic. This study was based primarily on the geological structure interpretation of seismic profiles, applying the theories and methods of basin dynamics, structural analysis and tectono-stratigraphic analysis, the geometry and kinematics features of the fault systems in the Bachn uplift were analyzed in detail. Our study shows that each fault belt is mainly characterized by compression and overthrusting, most of the faults initiated and activated during the Mid-Late Himalayan period, and that the general structural styles of the Bachu uplift were basement-involved pop-up thrust faulted block uplift, of which the southern margin was covered by the large-scale decollement fault system. The basement-involved structures widely developed in the higher position of the basement uplift, while decollement fault system developed mainly at the position with gypsum mudstone. The evolution process of Bachu uplift included back-bulge slope of the peripheral foreland basin in Mid-Late Caledonian, forebulge in HercynianYanshanian and the latest compressional faulted block uplift in Mid-Late Himalayan. Meanwhile,the study also suggests that the formation, reconstruction and stabilization of the uplift were controlled by the development and evolution of fault systems clearly. In the early forebulge stage, it was mainly presented as flexural deformation without the developing of thrust faults in the Bachu area; to the late stage, under the influence of violent lateral compression deformation, the faulted block uplift formed finally.
