Dynamic fluvial systems and gravel progradation in the Himalayan foreland

Abstract

Research Article| March 01, 2000 Dynamic fluvial systems and gravel progradation in the Himalayan foreland Nicholas Brozovic; Nicholas Brozovic 1Department of Earth Sciences, University of Southern California, Los Angeles, California 90089 Search for other works by this author on: GSW Google Scholar Douglas W. Burbank Douglas W. Burbank 1Department of Earth Sciences, University of Southern California, Los Angeles, California 90089 Search for other works by this author on: GSW Google Scholar GSA Bulletin (2000) 112 (3): 394–412. https://doi.org/10.1130/0016-7606(2000)112<394:DFSAGP>2.0.CO;2 Article history received: 22 May 1997 rev-recd: 12 Jul 1999 accepted: 02 Sep 1999 first online: 01 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Tools Icon Tools Get Permissions Search Site Citation Nicholas Brozovic, Douglas W. Burbank; Dynamic fluvial systems and gravel progradation in the Himalayan foreland. GSA Bulletin 2000;; 112 (3): 394–412. doi: https://doi.org/10.1130/0016-7606(2000)112<394:DFSAGP>2.0.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search nav search search input Search input auto suggest search filter All ContentBy SocietyGSA Bulletin Search Advanced Search Abstract Although the large-scale stratigraphy of many terrestrial foreland basins is punctuated by major episodes of gravel progradation, the relationships of such facies to hinterland tectonism and climate change are often unclear. Structural reentrants provide windows into older and more proximal parts of the foreland than are usually exposed, and thus provide key insights to earlier phases of foreland evolution. Our magnetostratigraphic studies show that, although the major lithofacies preserved within the Himachal Pradesh structural reentrant in northwestern India resemble Neogene facies in Pakistan, they have a much greater temporal and spatial variability. From 11.5 to 7 Ma, major facies boundaries in Himachal Pradesh vary by as much as 2–3 m.y. across distances of 20–30 km and are controlled by the interference between a major southeastward-flowing axial river and a major southwestward-flowing transverse river. A thick but highly confined middle to late Miocene conglomerate facies includes the oldest extensive Siwalik conglomerates yet dated (10 Ma) and implies the development of significant erosional topography along the Main Boundary thrust prior to 11 Ma. Our studies document extensive syntectonic gravel progradation with conglomerates extending tens of kilometers into the undeformed foreland during a period of increased subsidence rate and within 1–2 m.y. of major thrust initiation. Overall, gravel progradation is modulated by the interplay among subsidence, sediment supply, and the proportion of gravels in rivers entering the foreland. You do not currently have access to this article.