Extension and subsidence adjacent to a "weak" continental transform: An example from the Rukwa rift, East Africa

Abstract

Research Article| July 01, 1994 Extension and subsidence adjacent to a "weak" continental transform: An example from the Rukwa rift, East Africa W. H. Wheeler; W. H. Wheeler 1Department of Geology, Duke University, Durham, North Carolina 27708 Search for other works by this author on: GSW Google Scholar J. A. Karson J. A. Karson 1Department of Geology, Duke University, Durham, North Carolina 27708 Search for other works by this author on: GSW Google Scholar Author and Article Information W. H. Wheeler 1Department of Geology, Duke University, Durham, North Carolina 27708 J. A. Karson 1Department of Geology, Duke University, Durham, North Carolina 27708 Publisher: Geological Society of America First Online: 02 Jun 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 Geological Society of America Geology (1994) 22 (7): 625–628. https://doi.org/10.1130/0091-7613(1994)022<0625:EASATA>2.3.CO;2 Article history First Online: 02 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation W. H. Wheeler, J. A. Karson; Extension and subsidence adjacent to a "weak" continental transform: An example from the Rukwa rift, East Africa. Geology 1994;; 22 (7): 625–628. doi: https://doi.org/10.1130/0091-7613(1994)022<0625:EASATA>2.3.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGeology Search Advanced Search Abstract The Rukwa rift is a 300-km-long half-graben basin that lies along the central part of a 1000-km-long continental transform in the East African Rift. The basin contains Carboniferous to Quaternary sedimentary strata ∼11 km thick. Within the basin, maximum extension has been directed nearly normal to the border fault, even though this border fault has been dominated by dextral strike slip. However, extension and subsidence in the Rukwa rift are not explained by releasing-bend or oblique-extension fault geometries. We interpret the orientation of the extension as a local stress rotation symptomatic of a low- friction, "weak" strike-slip border fault. Structural and morphologic features suggest that an along-strike contrast in the frictional strength of the border fault controls the location of this extension. Subsidence and extension normal to the border fault in the Rukwa rift occur along a weak transform fault segment, as an along-strike accommodation of drag and local shortening against an adjacent strong segment. Thus, three-dimensional strain is accommodated differently along the strike of the border fault as a function of the frictional strength of the fault zone. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.