Resolving the argument about volcanic bedrock under the West Antarctic Ice Sheet and implications for ice sheet stability and sea level change

نویسندگان

چکیده

We provide a test for recent arguments that the West Antarctic Ice Sheet (WAIS) is underlain by an extensive outcrop of volcanic rock (mainly basalt) examining non-clay and clay mineral composition sediments collected in front under Ross Shelf. If proposed large volume were present, then we posit glacial erosion transport would deliver to Sea enriched minerals diagnostic alkaline basalt, namely olivine, pyroxene, plagioclase, no quartz. Using quantitative X-ray diffraction analysis, determine weight percent dolerite, gneiss, granite bedrock, compare these with suite 49 surface near-surface sediment samples from 1400 km west east transect across Sea. Fifty had quartz percentage values >25% very small wt percentages basalt minerals. A unmixing algorithm, gneiss end members, showed contained virtually was dominated compositions, but did show some admixture material derived Ferrar which crops out extensively Transantarctic Mountains. Indicators possible late Cenozoic bedrock – forsterite, smectite decrease opposite trend percent. Our study provides support presence WAIS, hence indicates any changes ice stream stability will not be influenced basal heat regime.

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ژورنال

عنوان ژورنال: Earth and Planetary Science Letters

سال: 2021

ISSN: ['1385-013X', '0012-821X']

DOI: https://doi.org/10.1016/j.epsl.2021.117035