Abstract Sea floor and shallow seismic data sets of terminal submarine fan lobes can provide excellent planform timeslices distributive deep‐water systems but commonly only limited information on cross‐sectional architecture. Extensive outcrops in the Tanqua depocentre, south‐west Karoo Basin, these three‐dimensional constraints lithofacies distributions, stacking patterns, depositional geometries stratigraphic evolution lobe deposits at a scale comparable with modern systems. Detailed study...

Submarine gravity flows are a key process for transporting large volumes of sediment from the continents to deep sea. The location, volume, and character bypassed by these dictates areal extent thickness associated deposits. Despite its importance, bypass is poorly understood in terms flow processes stratigraphic expression. We first examine relationships between physical parameters that govern flows, before assessing variable expression modern seafloor, outcrop, subsurface datasets....

Abstract The integration of correlated outcrop and newly acquired core wireline logs, extensive paleocurrent data, accurately mapped surfaces has enabled a common model the stratigraphic evolution to be developed four Permian fine-grained submarine fan systems (Fans 1–4) from Tanqua depocenter, SW Karoo Basin, South Africa. Additionally, this data revealed influence subtle seabed topography on systems' boundaries, internal facies architecture, directions. Furthermore, stratigraphy individual...

Abstract: Two seismic-scale submarine channel–levee systems exposed in the Karoo Basin, South Africa provide insights into slope conduit evolution. Component channel fills a levee-confined system (Unit C) and an entrenched D) follow common stacking patterns; initial horizontal (lateral migration) is followed by vertical (aggradation). This architecture response to equilibrium profile shift from low accommodation (slope degradation, composite erosion surface formation, external levee...

A widely misused criterion to interpret lobe deposits in submarine fan systems at outcrop, and core well logs, is a thickening and/or coarsening upward profile. Lobe from the Laingsburg depocentre, SW Karoo Basin, demonstrate that full range of bed thickness patterns exists within lobes. When lobes are defined by their laterally extensive bounding surfaces marked abrupt facies changes, five types stacking identified: upward, thinning then constant. The interpreted record avulsion feeder...

Abstract Sedimentary facies in the distal parts of deep‐marine lobes can diverge significantly from those predicted by classical turbidite models, and sedimentological processes these environments are poorly understood. This gap may be bridged using outcrop studies theoretical models. In Skoorsteenberg Formation (South Africa), a downstream transition thickly bedded sandstones to argillaceous, internally layered hybrid beds, is observed. The beds have characteristic stratigraphic spatial...

Submarine lobe fringe deposits form heterolithic successions that may include a high proportion of hybrid beds.The identification aids interpretation paleogeographic setting and the degree basin confinement.Here, for first time, sedimentological architectural differences between frontal lateral are investigated.Extensive outcrop core data from Fan 4, Skoorsteenberg Formation, Karoo Basin, South Africa, allow rates style facies changes axis to settings lobes complexes in both down-dip...

Abstract Observations from outcrop and subsurface datasets indicate that key stratigraphic surfaces in ancient submarine slope successions are diachronous form during periods of seascape degradation sediment bypass. Evidence for time transgressive confinement channel–levee systems includes composite basal erosion surfaces, cut-off bends hanging valleys, external levees overlying lobe deposits. After the onset a supply cycle, progressive will develop on slope, through combination incision...

Abstract Deep‐water mudstones are often considered as background sediments, deposited by vertical suspension fallout, and the range of transport depositional processes poorly understood compared with their shallow‐marine counterparts. This study presents a dataset from 538·50 m thick cored succession through Permian muddy lower Ecca Group Tanqua depocentre (south‐west Karoo Basin, South Africa). aims to characterize mudstone facies, processes, stacking patterns recorded in deep‐water...

Abstract Flutes and tool marks are commonly observed sedimentary structures on the bases of sandstones in deep‐water successions. These sole universally used as palaeocurrent indicators but, sharp contrast to most structures, they not palaeohydraulic reconstructions or aid prediction spatial distribution sediments. Since Kuenen's famous 1953 paper, flutes systems have been linked turbidity currents, reflected standard Bouma sequence taught generations geologists. Yet, these present a series...

Research Article| August 01, 2009 U-Pb zircon ages from the southwestern Karoo Basin, South Africa—Implications for Permian-Triassic boundary Andrea Fildani; Fildani 1Chevron Energy Technology Company, 6001 Bollinger Canyon Road, San Ramon, California 94583, USA Search other works by this author on: GSW Google Scholar Amy Weislogel; Weislogel 2Department of Geological Sciences, University Alabama, Tuscaloosa, Alabama 35487, Nicholas J. Drinkwater; Drinkwater 3Chevron Southern African...

Abstract Sediment gravity flows have a propensity to infill lows and build depositional relief, which influences subsequent flows. This flow–deposit interaction is intrinsic the evolution of submarine fans at range scales. A novel approach presented that assesses turbidity currents with subtle but evolving topography. Conceptual models developed from outcrop observations are tested process-based numerical model. The dataset was collected lobe deposits extensively exposed in Tanqua...

Abstract The Laingsburg depocenter of the SW Karoo Basin, South Africa, includes a series sandstone-dominated deepwater clastic deposits (units A and B Formation Unit C to G overlying Fort Brown Formation) separated vertically by regional mudstones records basin-floor upper-slope deposition during Permian icehouse climate. provides nearly continuous exposures over tens kilometers, presence regionally persistent internal mudstone markers (lower upper mudstones) allows distribution sedimentary...

Along the >650 km long southern margin of Karoo Basin in South Africa, we traversed four evenly spaced stratigraphic transects and collected 22 samples volcanic, air-fall tuffs thought to be distal deposits derived from Permian–Triassic Southern Gondwanan volcanic arc. We present 469 new U-Pb zircon ages determined by sensitive high-resolution ion microprobe reverse geometry (SHRIMP-RG) at Stanford–USGS Microanalytical Center order constrain maximum depositional for strata. Weighted means...

Research Article| May 07, 2018 Deep-water channel-lobe transition zone dynamics: Processes and depositional architecture, an example from the Karoo Basin, South Africa Hannah L. Brooks; Brooks † 1Stratigraphy Group, School of Earth Environment, University Leeds, LS2 9JT, UK †eehlb@leeds.ac.uk Search for other works by this author on: GSW Google Scholar David M. Hodgson; Hodgson Rufus Brunt; Brunt 2Stratigraphy Environmental Sciences, Manchester, M13 9PL, Jeff Peakall; Peakall Menno Hofstra;...