Granulometric analysis of glacial sediments, Schirmacher Oasis, East Antarctica

Abstract

Granulometric analysis of nineteen sediment samples has been carried out for their statistical and textural parameters. The samples are collected from the northern and southern margins of Schirmacher Oasis extending below the polar ice sheet and grading to coastal area respectively and main rocky land of Schirmacher including lakes. The analysis shows that most of the sediments are of medium grain size and fall in poor to very poor sorted category.An attempt has been made to interpret the depositional set-up by plotting the scatter patterns between various textural parameters, including C-M plot and arithmetic log-probability curves. The influence of physical parameters viz. low to high velocity winds, ice and meltwater on sediment characteristics has been discussed.

Textural characteristics, distribution pattern and provenance of heavy minerals in glacial sediments of Schirmacher Oasis, east Antarctica

“…About hundred grams of sample, free from carbonates and organic materials, which was prepared for granulometric analysis (Srivastava and Khare, 2009) were subjected for sieve-analysis. Further, ten gms of fine-sand fraction, passed through 80 mesh-size sieve and retained on 120 mesh have been taken for the separation of heavy and light fractions by gravitational settling method, using Bromoform (sp.…”

Glacial–interglacial climatic variations at the Schirmacher Oasis, East Antarctica: The first report from environmental magnetism

“…1). It consists of several hills of low elevation (~200 m; Srivastava and Khare, 2009) and about 120 lakes which may be classified as epishelf, proglacial and landlocked, depending on their geomorphic evolution (Ravindra, 2001). Sandy Lake (70°45′45.9″S; 11°47′34.7″E) is one of the small, land-locked lakes (Fig.…”

Grain-size characteristics of deposits derived from different glacigenic environments of the Schirmacher Oasis, East Antarctica

“…Thirty-seven samples have been collected. Eighteen of them are new; nineteen have been described earlier (Srivastava & Khare, 2009). The samples consist of loose admixtures of sand, silt and clay in variable proportions.…”

“…the wind. Recently, Srivastava et al (2009) differentiated the sediments of various glacial units on the basis of their grain-size characteristics. They also studied the roles of the depositional agents and the geomorphology and concluded that it is difficult to differentiate the sediments of the various areas on the basis of their grainsize parameters, but this conclusion was based on the analysis of nineteen samples only.…”

“…polar ice, the ice-free area (in the sense of neither being covered by glacial ice, nor being a lake), lakes and the coastal shelf region, and (3) to establish the group variances between the sediments from these four are types. This study is based on thirty-seven samples, including the nineteen samples that had been analysed earlier (Srivastava & Khare, 2009). The new results should provide more details and more accurate data than the earlier findings, also because statistical analyses have now been applied.…”