Research Article| October 01, 2002 Structural segmentation, inversion, and salt tectonics on a passive margin: Evolution of the Inner Kwanza Basin, Angola Michael R. Hudec; Michael R. Hudec 1Bureau of Economic Geology, University of Texas, Box X, University Station, Austin, Texas 78713-8924, USA Search for other works by this author on: GSW Google Scholar Martin P.A. Jackson Martin P.A. Jackson 1Bureau of Economic Geology, University of Texas, Box X, University Station, Austin, Texas 78713-8924, USA Search for other works by this author on: GSW Google Scholar GSA Bulletin (2002) 114 (10): 1222–1244. https://doi.org/10.1130/0016-7606(2002)114<1222:SSIAST>2.0.CO;2 Article history received: 06 Aug 2001 rev-recd: 06 Mar 2002 accepted: 22 Mar 2002 first online: 01 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share MailTo Twitter LinkedIn Tools Icon Tools Get Permissions Search Site Citation Michael R. Hudec, Martin P.A. Jackson; Structural segmentation, inversion, and salt tectonics on a passive margin: Evolution of the Inner Kwanza Basin, Angola. GSA Bulletin 2002;; 114 (10): 1222–1244. doi: https://doi.org/10.1130/0016-7606(2002)114<1222:SSIAST>2.0.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 SocietyGSA Bulletin Search Advanced Search Abstract The Kwanza Basin, Angola, is divided into the Inner and Outer Kwanza salt basins, separated by a chain of synrift basement highs on which Aptian (112–122 Ma) salt is thin or absent. North- to northwest-trending basement structures in the Inner Kwanza Basin have repeatedly been reactivated since Neocomian (144–127 Ma) rifting. Reactivation formed three northwest-striking fold-and-thrust belts near basement uplifts. The thrust belts are bounded by northeast-striking rift-related transfer-fault zones that were apparently reactivated during subsequent shortening. Three episodes of postrift, basement-involved shortening are documented in the Inner Kwanza Basin: (1) Albian–early Cenomanian (112–96 Ma), (2) Senonian (89–65 Ma), and (3) Oligocene–Holocene (34–0 Ma). We relate the Albian–early Cenomanian event to ridge push, the Senonian event to global-plate reorganization, and Oligocene–Holocene shortening to uplift of the African superswell.Structural segmentation of the Inner Kwanza Basin controlled the evolution of salt structures. Adjacent to basement uplifts, diapirs were initiated as buckle folds. Some anticlines were unroofed by erosion and evolved into passive salt walls. Elsewhere, broad salt walls were triggered by either detached extension or basement-block uplift. These walls grew until they exhausted their supply of salt. Thereafter, dissolution rates exceeded rates of salt inflow, so the walls began to subside. Withdrawal of salt from the walls produced the elongate sedimentary troughs for which the basin is famous. Trough fill ranges in age from Cenomanian to Pliocene, and this age varies greatly from trough to trough and along strike within troughs. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.