Late Cretaceous to Recent post-breakup evolution of the African S-Atlantic margin: integrating onshore field studies; sequence development, offshore seismic data, numerical dating and modelling

点击翻译按钮获取中文摘要

Multiple phases of volcanism, uplift and subsidence are recorded after the breakup of the Namibian South Atlantic margin segment – features which are regarded as atypical when compared to published examples of other post-breakup continental margin successions. It is currently not understood whether these geodynamic processes are only of regional or a broader, South Atlantic intercontinental importance. Existing low T thermochronometric analyses, cosmogenic isotope measurements on bedrock surfaces and tectonic and stratigraphic analysis of the post-breakup succession could be advantageously completed and calibrated by (A) the interpretation of offshore industrial seismic and well log data (uppermost 2s TWT) and (B) the analysis of onshore sedimentary archives such as post-breakup fluvial depositional sequences, marine terraces, aeolianites, palaeo-seacliffs, incised valleys and syntectonic strata in the hanging-walls of normal faults. Both, onshore and offshore strata provide a high-resolution archive of processes accompanying the breakup and post-breakup evolution of the South Atlantic margin. Many of the coastal marine terraces contain dateable material suitable for biostratigraphic analysis combined with ESR and OSL dating. Offshore seismic structural and stratigraphic analysis and well data will be integrated with a detailed 3D stratigraphic and structural analysis as well as dynamic retro- and forward modelling which forms the basis for a combined 3D onshore-offshore surface-subsurface model.