Currently in Niu-zhuang sub-sag, the seismic reflection amplitude of the newly discovered turbidite sandstone is stronger in the third Segment. The main reason is that Calcareous components accounts for a large part a...Currently in Niu-zhuang sub-sag, the seismic reflection amplitude of the newly discovered turbidite sandstone is stronger in the third Segment. The main reason is that Calcareous components accounts for a large part and physical properties is relatively poor, which results in no corresponding relation between reservoir and seismic attributes, and effective reservoir is difficult to predict and describe. Therefore, using the method of geological statistics, we firstly study the distribution of calcareous matters, secondly study the contribution to seismic reflection amplitude made by Calcareous high impedance component;thirdly analyze its influence on actual seismic reflection amplitude and determine the lithology thickness of Calcareous via replacement forward modeling. At last, we characterize the reservoir using the amplitude of calcareous matters. It proves that the method of seismic-geological comprehensive prediction is reliable. It has good guidance for exploration and development of the calcareous sand lithologic reservoir in similar areas.展开更多
The unequivocal identification of soft-sediment deformation structures(SSDS)is a significant attribute to constrain the effect of transient geological events in the spatio-temporal evolution of ancient sedimentary bas...The unequivocal identification of soft-sediment deformation structures(SSDS)is a significant attribute to constrain the effect of transient geological events in the spatio-temporal evolution of ancient sedimentary basins.This paper reports and discusses,for the first time,the occurrence of several cm-to dm-scale SSDS within sandstone successions of the Mesoproterozoic Kaimur Group(Vindhyan Supergroup),exposed at the Hanumandhara Hill of Chitrakoot-Satna border region,Madhya Pradesh State,India.The SSDS are confined to a deformed interval comprising seven individual sedimentary units of variable composition and texture,which are sandwiched between nearly horizontally undeformed sandstone beds.The SSDS consist of load structures(load casts,flame structures,pseudonodules and ball-and-pillow structures),contorted lamination,convolute lamination,boudins and pinch-and-swell structures,deformed cross-stratification,slump structures,clastic injections,fluid escape structures,and syn-sedimentary fractures/faults.The pre-sent study suggests that the formation of these SSDS is essentially related to a combination of processes(gravitational instability,liquefaction,fluidization,and fluid escape)predominantly induced by seismic shocks.In addition,the restricted occurrence of fractures/faults in these deformed layers emphasizes the passage of seismically-induced Rayleigh waves.Considering the observed types of SSDS,their lateral homo-geneity and geographic distribution along with the geodynamic framework of the Vindhyan Basin,the whole area can be tentatively attributed to having experienced moderate-to high-magnitude(M≥5)seismicity.The present study combined with earlier reports of seismically-induced SSDS,from other regionally disposed formations belonging to the Lower(e.g.,Kajrahat Limestone,Chopan Porcellanite,Koldaha Shale,Rohtas Limestone,and Glauconitic Sandstone of the Semri Group)and Upper(e.g.,Bhander Limestone of the Bhander Group)Vindhyan Supergroup,respectively,provides evidence for the constant regional-scale s展开更多
文摘Currently in Niu-zhuang sub-sag, the seismic reflection amplitude of the newly discovered turbidite sandstone is stronger in the third Segment. The main reason is that Calcareous components accounts for a large part and physical properties is relatively poor, which results in no corresponding relation between reservoir and seismic attributes, and effective reservoir is difficult to predict and describe. Therefore, using the method of geological statistics, we firstly study the distribution of calcareous matters, secondly study the contribution to seismic reflection amplitude made by Calcareous high impedance component;thirdly analyze its influence on actual seismic reflection amplitude and determine the lithology thickness of Calcareous via replacement forward modeling. At last, we characterize the reservoir using the amplitude of calcareous matters. It proves that the method of seismic-geological comprehensive prediction is reliable. It has good guidance for exploration and development of the calcareous sand lithologic reservoir in similar areas.
基金the Council of Scientific and Industrial Research, New Delhi, Government of India, for awarding him Shyama Prasad Mukherjee Fellowship [SPM-09/001(0328)/2020-EMRI]the Department of Science and Technology, Government of India, for the INSPIRE Fellowship [IF170168]
文摘The unequivocal identification of soft-sediment deformation structures(SSDS)is a significant attribute to constrain the effect of transient geological events in the spatio-temporal evolution of ancient sedimentary basins.This paper reports and discusses,for the first time,the occurrence of several cm-to dm-scale SSDS within sandstone successions of the Mesoproterozoic Kaimur Group(Vindhyan Supergroup),exposed at the Hanumandhara Hill of Chitrakoot-Satna border region,Madhya Pradesh State,India.The SSDS are confined to a deformed interval comprising seven individual sedimentary units of variable composition and texture,which are sandwiched between nearly horizontally undeformed sandstone beds.The SSDS consist of load structures(load casts,flame structures,pseudonodules and ball-and-pillow structures),contorted lamination,convolute lamination,boudins and pinch-and-swell structures,deformed cross-stratification,slump structures,clastic injections,fluid escape structures,and syn-sedimentary fractures/faults.The pre-sent study suggests that the formation of these SSDS is essentially related to a combination of processes(gravitational instability,liquefaction,fluidization,and fluid escape)predominantly induced by seismic shocks.In addition,the restricted occurrence of fractures/faults in these deformed layers emphasizes the passage of seismically-induced Rayleigh waves.Considering the observed types of SSDS,their lateral homo-geneity and geographic distribution along with the geodynamic framework of the Vindhyan Basin,the whole area can be tentatively attributed to having experienced moderate-to high-magnitude(M≥5)seismicity.The present study combined with earlier reports of seismically-induced SSDS,from other regionally disposed formations belonging to the Lower(e.g.,Kajrahat Limestone,Chopan Porcellanite,Koldaha Shale,Rohtas Limestone,and Glauconitic Sandstone of the Semri Group)and Upper(e.g.,Bhander Limestone of the Bhander Group)Vindhyan Supergroup,respectively,provides evidence for the constant regional-scale s
