Sediment deformational structures in quaternary sediment sequences of Kashmir basin India, with special reference to microstructures

Abstract

Quaternary sediment sequences deposited in the Kashmir basin show the cyclicity in the sedimentation patterns with fining upward sequences. The sediment successions show some abrupt changes in the deposition environment. The integrated sediment sequence of the basin preserves the number of soft sediment deformed structures sandwiched between the normal sedimentary structures. The detailed examination of these deformed as well as undeformed sediments within the successions using scanning electron microscope technique shows the presence of distinctive microstructural assemblages. The microstructures not only characterize the well distinct mineral constituents of Chlorites, Illites, Kaolinites, Halloysites and Smectites but also preserve some Chalk grains which results in the increase of porosity. Besides this, the sediments not only preserve the peculiar type of microstructures that signifies the depositional environment but also some distinct type of mechanically or wave generated microstructures which implies the influence of cyclic stressing or seismicity governed processes preserved within the sediments.

Keywords

• Kashmir basin
• Quaternary sediments
• Sediment cyclicity
• Microstructures
• Depositional environment
• Seismic stressing