The University of Southampton
University of Southampton Institutional Repository

Insights into the patterns and locations of erosion in the Himalaya — A combined fission-track and in situ Sm–Nd isotopic study of detrital apatite

Insights into the patterns and locations of erosion in the Himalaya — A combined fission-track and in situ Sm–Nd isotopic study of detrital apatite
Insights into the patterns and locations of erosion in the Himalaya — A combined fission-track and in situ Sm–Nd isotopic study of detrital apatite
Understanding the role that climate, erosion and tectonics play in determining the mean relief, elevation and general form of a mountain range over time has become the focus of much recent research in the field of tectonic geomorphology. A crucial constraint in these studies is the long-term exhumation rate, which is increasingly being examined using detrital minerals from the sedimentary rock record that represent the eroded remnants of the orogen. A classic field area of such studies is the Himalayan orogen — the Earth's largest mountain range. We describe here a novel approach that uses the in situ analysis of Nd isotopes by laser ablation multicollector inductively coupled plasma mass spectrometry of fission-track dated apatite grains to unambiguously tie them to their source regions. We demonstrate the capability of this new approach on several modern and Holocene river sand samples from the Himalayan orogen and determine, because of the large isotopic differences in the constituent tectonostratigraphic units, both the location and magnitude of long-term erosion. In agreement with previous studies we are able to show that in the Central and Eastern Himalaya long-term denudation is focussed within the High Himalayan Crystalline Series (HHCS) at average rates of not, vert, similar 2 mm/yr. Average long-term rates are similar in the Western Himalaya sampled by the Indus River and largely reflect erosional denudation of the Western Indian Himalaya and the Western Syntaxis (the Nanga Parbat Haramosh Massif and South Karakoram Metamorphic Complex). Notably, the Asian continent supplies significantly more apatites to the mouth of the Indus than they do to the Bengal delta. The ability to reconstruct the patterns of long-term erosion in the Himalaya using detrital apatites from a few samples collected from major transverse drainages provides confidence in the utility of this approach to examine the locations and magnitude of long-term erosion in the past.
0012-821X
407-418
Foster, G.L.
fbaa7255-7267-4443-a55e-e2a791213022
Carter, A
17c04f6a-0136-445f-a9af-eec923f405d6
Foster, G.L.
fbaa7255-7267-4443-a55e-e2a791213022
Carter, A
17c04f6a-0136-445f-a9af-eec923f405d6

Foster, G.L. and Carter, A (2007) Insights into the patterns and locations of erosion in the Himalaya — A combined fission-track and in situ Sm–Nd isotopic study of detrital apatite. Earth and Planetary Science Letters, 257 (3-4), 407-418. (doi:10.1016/j.epsl.2007.02.044).

Record type: Article

Abstract

Understanding the role that climate, erosion and tectonics play in determining the mean relief, elevation and general form of a mountain range over time has become the focus of much recent research in the field of tectonic geomorphology. A crucial constraint in these studies is the long-term exhumation rate, which is increasingly being examined using detrital minerals from the sedimentary rock record that represent the eroded remnants of the orogen. A classic field area of such studies is the Himalayan orogen — the Earth's largest mountain range. We describe here a novel approach that uses the in situ analysis of Nd isotopes by laser ablation multicollector inductively coupled plasma mass spectrometry of fission-track dated apatite grains to unambiguously tie them to their source regions. We demonstrate the capability of this new approach on several modern and Holocene river sand samples from the Himalayan orogen and determine, because of the large isotopic differences in the constituent tectonostratigraphic units, both the location and magnitude of long-term erosion. In agreement with previous studies we are able to show that in the Central and Eastern Himalaya long-term denudation is focussed within the High Himalayan Crystalline Series (HHCS) at average rates of not, vert, similar 2 mm/yr. Average long-term rates are similar in the Western Himalaya sampled by the Indus River and largely reflect erosional denudation of the Western Indian Himalaya and the Western Syntaxis (the Nanga Parbat Haramosh Massif and South Karakoram Metamorphic Complex). Notably, the Asian continent supplies significantly more apatites to the mouth of the Indus than they do to the Bengal delta. The ability to reconstruct the patterns of long-term erosion in the Himalaya using detrital apatites from a few samples collected from major transverse drainages provides confidence in the utility of this approach to examine the locations and magnitude of long-term erosion in the past.

This record has no associated files available for download.

More information

Published date: 30 May 2007

Identifiers

Local EPrints ID: 155375
URI: http://eprints.soton.ac.uk/id/eprint/155375
ISSN: 0012-821X
PURE UUID: 52861c6c-4d18-4cdf-8eff-e783da818524
ORCID for G.L. Foster: ORCID iD orcid.org/0000-0003-3688-9668

Catalogue record

Date deposited: 27 May 2010 13:40
Last modified: 14 Mar 2024 02:55

Export record

Altmetrics

Contributors

Author: G.L. Foster ORCID iD
Author: A Carter

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of http://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×