Post-rift stratigraphic evolution of the Atlantic margin of Namibia and South Africa: Implications for the vertical movements of the margin and the uplift history of the South African Plateau

Baby, Guillaume; Guillocheau, François; Morin, J.; Ressouche, Jonas; Robin, Cécile; Broucke, Olivier; Dall’Asta, Massimo

doi:10.1016/j.marpetgeo.2018.06.030

Cited by 40 publications

(123 citation statements)

References 65 publications

Supporting

Mentioning

121

Contrasting

Order By: Relevance

“…Over the last two decades, high‐resolution seismic data and thermochronology data have improved our understanding of the tectonic and geomorphic evolution of Southern Africa (Baby et al, ; Baby et al, ; Brown et al, ; Guillocheau et al, ; Said et al, ; Stanley et al, ; Tinker et al, ). For example, Hu et al () recently proposed a lithospheric delamination model for the uplift history of southern Africa based on seismic observations and geodynamic modeling.…”

Section: Application To Southern Africamentioning

confidence: 99%

Drainage and Sedimentary Responses to Dynamic Topography

Ding

Salles

Flament

et al. 2019

Geophysical Research Letters

View full text Add to dashboard Cite

Dynamic topography due to mantle flow contributes to shaping Earth's evolving landscapes by affecting sediment routing, which has rarely been explored in source-to-sink contexts. Here we design a generic model to investigate the impact of dynamic topography on both landscape evolution and stratigraphic formations. An imposed wave of dynamic topography propagates laterally under a fixed continent, exerting transient surface uplift and subsidence. We find that a migrating dynamic topography can induce significant drainage reorganizations and affect sediment routing from source to sink. Variations in sediment supply driven by the lateral migrating dynamic topography contribute to the formation of diachronous unconformities along the margin. The predicted sediment flux histories are then put into perspective with the Cretaceous sedimentary records along the Southern African margins. Finally, we demonstrate that correlating offshore depositional hiatuses and unconformities has the potential to constrain the spatiotemporal evolution of past dynamic topography events. Plain Language Summary Convective motion within Earth's interior result in transient upliftand subsidence of the surface is called dynamic topography. This process slowly shapes landscapes over millions of years and identifying its fingerprints in the rock record remains a challenge. This study uses numerical modeling to investigate the erosional and depositional response of landscapes to sea level change and to mantle flow. We show that unlike sea level change, dynamic topography reorganizes river flows and changes sediment supply to offshore regions, generating various stratal patterns. We model a simple circular landscape that evolves similarly to the southern African landscape between 140 and 66 million years ago and suggest sedimentary fingerprints to link the evolution of the Earth's surface to the dynamics of its deep interior.

show abstract

Section: Application To Southern Africamentioning

confidence: 99%

Drainage and Sedimentary Responses to Dynamic Topography

Ding

Salles

Flament

et al. 2019

Geophysical Research Letters

View full text Add to dashboard Cite

show abstract

“…Tectonic forcing operates on many temporal and spatial scales, from long-lived collision of continental plates, to changes in lithospheric stress, mantle dynamics and short-lived, intracatchment fault movements. Whereas local fault activity can result in rapid changes in sediment supply (Whittaker et al, 2010), perturbations related to mantle dynamics and plate tectonic processes can cause re-arrangement of entire continentscale fluvial networks and often result in distinct changes in basin physiography and accommodation trends that can readily be recognized in the deep-time (>10ˆ6 yr) depositional record (e.g., Campanile et al, 2008;Baby et al, 2018). The impact of such tectonic perturbations have be inferred qualitatively by linking pulses of coarse-grained material to phases of magmatic activity (e.g., White and Lovell, 1997), and quantitatively by analyzing sediment mass budgets linked to inferred changes in onshore denudation rates (Jones et al, 2002;Tinker et al, 2008;Braun et al, 2014).…”

Section: Introductionmentioning

confidence: 99%

Manifestation of Tectonic and Climatic Perturbations in Deep-Time Stratigraphy – An Example From the Paleocene Succession Offshore Western Norway

Sømme

Skogseid

Embry³

et al. 2019

Front. Earth Sci.

View full text Add to dashboard Cite

“…Recent work on the Atlantic offshore marine stratigraphy suggests that the main river depocenter was located south of the current outlet near the present-day Olifants River mouth prior to ca. 113 Ma (Baby et al, 2018b). Deposition then moved to a proto-Orange River delta slightly south of the modern Orange River outlet at 113 Ma, with the current Orange River delta becoming active by 93 Ma (Brown et al, 1995;Baby et al, 2018b).…”

Section: Topography and Orange River Evolutionmentioning

confidence: 99%

“…All paleo-drainage reconstructions for southern Africa suggest that the majority of the subcontinent has been westward-draining since the Cretaceous, likely since Gondwana breakup (Dingle and Hendey, 1984;Partridge and Maud, 1987;de Wit, 1999). Evidence for this comes from reconstructed post-135 Ma sedimentary fluxes to the adjacent marine basins, with fluxes offshore to the west that are an order of magnitude higher than to the east and south (Tinker et al, 2008a;Guillocheau et al, 2012;Baby et al, 2018bBaby et al, , 2018a. Additionally, large deposits of alluvial diamonds are found only in river terrace deposits of the lower Orange River and along the west coast, with their diamondiferous kimberlite sources located in the central and eastern plateau (de Wit, 1999;Bluck et al, 2005;Nakashole et al, 2018;Phillips et al, 2018).…”

Section: Topography and Orange River Evolutionmentioning

confidence: 99%

See 1 more Smart Citation

Mesozoic denudation history of the lower Orange River and eastward migration of erosion across the southern African Plateau

Stanley

Flowers

2020

Lithosphere

View full text Add to dashboard Cite

Topographic uplift of the southern African Plateau is commonly attributed to mantle causes, but the links between mantle processes, uplift, and erosion patterns are not necessarily straightforward. We acquired apatite (U-Th)/He (AHe) dates from eight kimberlite and basement samples from the lower reaches of the large westward-draining Orange River system with the goal of evaluating the roles of lithospheric modification and river incision on the erosion history here. Average AHe dates range from 79 to 118 Ma and thermal history models suggest that most samples are consistent with a main erosion phase at ca. 120–100 Ma, with some variability across the region indicating a complex erosion history. Major erosion overlaps with the timing of strong lithospheric thermochemical modification as recorded in xenoliths from the studied kimberlites, but the denudation pattern does not mimic the northward progression of lithospheric alteration across the study region. We attribute this area’s denudation history to a combination of mantle effects, rifting, establishment of the Orange River outlet at its current location, and later faulting. When considering these results with other kimberlite-derived surface histories from an ∼1000-km-long E-W transect across the plateau, an eastward-younging trend in denudation is evident. The interplay of mantle processes and the shape of the large, west-draining Orange River basin likely control this first order-pattern.

show abstract

Post-rift stratigraphic evolution of the Atlantic margin of Namibia and South Africa: Implications for the vertical movements of the margin and the uplift history of the South African Plateau

Cited by 40 publications

References 65 publications

Drainage and Sedimentary Responses to Dynamic Topography

Drainage and Sedimentary Responses to Dynamic Topography

Manifestation of Tectonic and Climatic Perturbations in Deep-Time Stratigraphy – An Example From the Paleocene Succession Offshore Western Norway

Mesozoic denudation history of the lower Orange River and eastward migration of erosion across the southern African Plateau

Contact Info

Product

Resources

About