CRYOGENIC DIAGENESIS AS THE CAUSE OF ICE DEPOSITS IN ARCTIC MARINE SEDIMENTS

Abstract

The sediments of polar seas that now lie in the frozen-rock zone contain stratiform, lenticular, and more complex deposits of buried ice. They are most common in near-shore facies, in stratified sands and silts and in clays and loams rich in dispersed organic matter. The ice deposits and the surrounding sediments most often are plastically deformed. The deformations consist of folds that taper out with depth in the section. The mechanism by which these ice deposits form in marine sediments is still unclear in many respects. An analysis of data on the composition, texture and bedding of the ice deposits in Arctic marine sediments indicates that in many cases they were produced by terrestrial fresh-water springs in the inshore zones of Arctic seas. This paper presents diagram of the development of buried deposits of low-salinity ice in below-zero marine sediments with simultaneous deformation. This theory gives a satisfactory explanation of many features that cannot otherwise be accounted for and reveals new aspects of the subject of cryogenic lithogenesis under marine sedimentation conditions.