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Regional Pliocene exhumation of the Lesser Himalaya in the Indus drainage


Title (Dublin Core)

Regional Pliocene exhumation of the Lesser Himalaya in the Indus drainage

Description (Dublin Core)

<p>New bulk sediment Sr and Nd isotope data, coupled with U–Pb dating
of detrital zircon grains from sediment cored by the International Ocean
Discovery Program in the Arabian Sea, allow the reconstruction of erosion in the
Indus catchment since <span class="inline-formula">∼17</span>&thinsp;Ma. Increasing <span class="inline-formula"><i>ε</i><sub>Nd</sub></span> values from 17 to 9.5&thinsp;Ma imply relatively more erosion from the
Karakoram and Kohistan, likely linked to slip on the Karakoram Fault and
compression in the southern and eastern Karakoram. After a period of
relative stability from 9.5 to 5.7&thinsp;Ma, there is a long-term decrease in
<span class="inline-formula"><i>ε</i><sub>Nd</sub></span> values that corresponds with increasing relative
abundance of <span class="inline-formula">&gt;300</span>&thinsp;Ma zircon grains that are most common in
Himalayan bedrocks. The continuous presence of abundant Himalayan zircons
precludes large-scale drainage capture as the cause of decreasing
<span class="inline-formula"><i>ε</i><sub>Nd</sub></span> values in the submarine fan. Although the initial
increase in Lesser Himalaya-derived 1500–2300&thinsp;Ma zircons after 8.3&thinsp;Ma is
consistent with earlier records from the foreland basin, the much greater
rise after 1.9&thinsp;Ma has not previously been recognized and suggests that
widespread unroofing of the Crystalline Lesser Himalaya and to a lesser
extent Nanga Parbat did not occur until after 1.9&thinsp;Ma. Because regional
erosion increased in the Pleistocene compared to the Pliocene, the relative
increase in erosion from the Lesser Himalaya does not reflect slowing
erosion in the Karakoram and Greater Himalaya. No simple links can be made
between erosion and the development of the South Asian Monsoon, implying a
largely tectonic control on Lesser Himalayan unroofing.</p>

Creator (Dublin Core)

P. D. Clift
P. Zhou
D. F. Stockli
J. Blusztajn

Subject (Dublin Core)


Publisher (Dublin Core)

Copernicus Publications

Date (Dublin Core)


Type (Dublin Core)


Identifier (Dublin Core)


Source (Dublin Core)

Solid Earth, Vol 10, Pp 647-661 (2019)

Language (Dublin Core)


Relation (Dublin Core)

Provenance (Dublin Core)

Journal Licence: CC BY