کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
4729967 1640345 2016 29 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Indus Basin sediment provenance constrained using garnet geochemistry
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات زمین شناسی
پیش نمایش صفحه اول مقاله
Indus Basin sediment provenance constrained using garnet geochemistry
چکیده انگلیسی


• We are the first to employ garnet geochemistry to discriminate provenance for Indus River system.
• Garnet geochemistry displays a unique signature for the Himalayan Rivers on the east of the Indus drainages compare to drainages in the western Himalayan region confining to Indus River System.
• Thar Dune sands are confined to the eastern part of Indus Basin and contains significant detrital garnet grains that are unique for western drainages. We argue these likely sourced from the western drainage that are reworked by the monsoon winds.

The chemical and mineralogical diversity of western Himalayan rivers is the result of each of them draining different tectonic and lithologic units, whose character is partly transferred to the sediments carried by those rivers. Garnet geochemistry was employed to discriminate provenance in the Indus River system. We characterized the geochemistry of garnet sediment grains from the modern Indus and all its major tributaries, as well as the related but ephemeral Ghaggar-Hakra River and dune sand from the Thar Desert. Garnet geochemistry displays a unique signature for the Himalayan rivers on the east of the Indus drainage compared to those in the western drainage. The trunk Indus remains distinct because of the dominant arc-type pyrope-garnet derived from Kohistan and the Karakoram. The Jhellum, which lies just east of the modern Indus has modest concentrations of arc-type pyrope garnets, which are more depleted in the other eastern tributaries. Their presence in the Jhellum reflects recycling of trunk Indus garnets through the Miocene Siwalik Group foreland sedimentary rocks. The Thar Desert dune sample contains significant numbers of grains similar to those in the trunk Indus, likely reworked by monsoon winds from the SW. Our data further indicate the presence of a Himalayan river channel east of the present Indus, close to the delta, in the Nara River valley during the middle Holocene. Sands from this channel cannot be distinguished from the Indus on the basis of their garnet geochemistry alone but we favour their sedimentation from an Indus channel rather than reworking of desert sands by another stream. The garnet geochemistry shows some potential as a provenance tool, but cannot be used alone to uniquely discriminate Indus Basin provenance.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Asian Earth Sciences - Volume 126, 15 August 2016, Pages 29–57
نویسندگان
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