Normal vs. strike-slip faulting during rift development in East Africa: The Malawi rift

Research Article| November 01, 1992 Normal vs. strike-slip faulting during rift development in East Africa: The Malawi rift Uwe Ring; Uwe Ring 1Institut für Geowissenschaften, Universität Mainz, Saarstrasse 21, D-6500 Mainz, Germany Search for other works by this author on: GSW Google Scholar Christian Betzler; Christian Betzler 2Geologisches Institut, Universität Frankfurt, Senckenberganlage 32-34, D6000 Frankfurt am Main, Germany Search for other works by this author on: GSW Google Scholar Damian Delvaux Damian Delvaux 3Musée Royal de l'Afrique Centrale, Leuvensesteenweg 13, B-3080 Tervuren, Belgium Search for other works by this author on: GSW Google Scholar Geology (1992) 20 (11): 1015–1018. https://doi.org/10.1130/0091-7613(1992)020<1015:NVSSFD>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 Uwe Ring, Christian Betzler, Damian Delvaux; Normal vs. strike-slip faulting during rift development in East Africa: The Malawi rift. Geology 1992;; 20 (11): 1015–1018. doi: https://doi.org/10.1130/0091-7613(1992)020<1015:NVSSFD>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 Kinematic analysis of Neogene and Quaternary faults demonstrates that the direction of extension in the Malawi rift rotated from east-northeast to southeast. Rift development commenced with the formation of half-grabens bounded by northwest-, north-, and northeast-striking normal faults. Owing to slightly oblique rifting, the northwest-striking faults in the northernmost rift segment show a small dextral oblique-slip component, whereas north- and northeast-oriented faults in the central part of the rift display a sinistral oblique-slip component. This first event resulted in block faulting and basin subsidence, which is largely responsible for the present-day basin morphology of Lake Malawi. A major change in fault kinematics occurred because of rotation of the extension direction and permutation of the principal compressive and intermediate axes. The structural pattern inherited from the first rifting phase was no longer suitably oriented to accommodate extensional deformation, and strike-slip faulting assumed a major role. The strike-slip regime amplified uplift of basement ridges within the rift in regions of local transpression, but it also created alluvial basins because of local transtension. This new kinematic style is compatible with the recent seismicity. Older faults that show mainly the first deformational increment are restricted to the outermost parts of the rift. Toward the center, the faults depict an increase in strike-slip components of movement, suggesting deformation propagation toward the rift center, which results in a narrowing of the active rift environments with time. 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.