Journal articles: 'Submarine fans – South Africa'

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Hodgson, David M. "Distribution and origin of hybrid beds in sand-rich submarine fans of the Tanqua depocentre, Karoo Basin, South Africa." Marine and Petroleum Geology 26, no. 10 (December 2009): 1940–56. http://dx.doi.org/10.1016/j.marpetgeo.2009.02.011.

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Adelmann, Dirk, and Kerstin Fiedler. "Origin and characteristics of Late Permian submarine fan and deltaic sediments in the Laingsburg subbasin (SW Karoo Basin, Cape Province/South Africa)." Zeitschrift der Deutschen Geologischen Gesellschaft 149, no. 1 (May 26, 1998): 27–38. http://dx.doi.org/10.1127/zdgg/149/1998/27.

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Boulesteix, Kévin, Miquel Poyatos-Moré, David M. Hodgson, Stephen S. Flint, and Kevin G. Taylor. "Fringe or background: Characterizing deep-water mudstones beyond the basin-floor fan sandstone pinchout." Journal of Sedimentary Research 90, no. 12 (December 31, 2020): 1678–705. http://dx.doi.org/10.2110/jsr.2020.048.

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ABSTRACT Mud dominates volumetrically the fraction of sediment delivered and deposited in deep-water environments, and mudstone is a major component of basin-floor successions. However, studies of basin-floor deposits have mainly focused on their proximal sandstone-prone part. A consequent bias therefore remains in the understanding of depositional processes and stratigraphic architecture in mudstone-prone distal settings beyond the sandstone pinchouts of basin-floor fans. This study uses macroscopic and microscopic descriptions of over 500 m of continuous cores from research boreholes from the Permian Skoorsteenberg Formation of the Karoo Basin, South Africa, to document the sedimentology, stratigraphy, and ichnology of a distal mudstone-prone basin-floor succession. Very thin- to thin-bedded mudstones, deposited by low-density turbidity currents, stack to form bedsets bounded by thin packages (< 0.7 m thick) of background mudstones. Genetically related bedsets stack to form bedset packages, which are bounded by thicker (> 0.7 m thick) background mudstones. Stratigraphic correlation between cores suggests that bedsets represent the distal fringes of submarine fan lobe elements and/or lobes, and bedset packages represent the distal fringes of lobe complexes and/or lobe complex sets. The internal stacking pattern of bedsets and bedset packages is highly variable vertically and laterally, which records dominantly autogenic processes (e.g., compensational stacking, avulsion of feeder channels). The background mudstones are characterized by remnant tractional structures and outsize particles, and are interpreted as deposited from low-density turbidity currents and debris flows before intense biogenic reworking. These observations challenge the idea that mud accumulates only from hemipelagic suspension fallout in distal basin-floor environments. Thin background mudstones separating bedsets (< 0.7 m thick) are interpreted to mainly represent autogenically driven lobe abandonment due to up-dip channel avulsion. The thicker background mudstones separating bedset packages (> 0.7 m thick) are interpreted to dominantly mark allogenically driven regional decrease of sand supply to the basin floor. The recognition of sandstone-prone basin-floor fans passing into genetically linked distal fringe mudstones suggests that submarine lobes are at least ∼ 20 km longer than previously estimated. This study provides sedimentological, stratigraphic, and ichnological criteria to differentiate mudstones deposited in different sub-environments in distal deep-water basin-floor settings, with implications for the accurate characterization of basin-floor fan architecture, and their use as archives of paleoenvironmental change.

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Le Roy, Pascal, Claire Gracia-Garay, Pol Guennoc, Jean-François Bourillet, Jean-Yves Reynaud, Isabelle Thinon, Patrick Kervevan, Fabien Paquet, David Menier, and Cédric Bulois. "Cenozoic tectonics of the Western Approaches Channel basins and its control of local drainage systems." Bulletin de la Société Géologique de France 182, no. 5 (September 1, 2011): 451–63. http://dx.doi.org/10.2113/gssgfbull.182.5.451.

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Abstract The geology of the Channel Western Approaches is a key to understand the post-rift evolution of the NW European continental margin in relation with the Europe/Africa collision. Despite considerable evidence of Tertiary tectonic inversion throughout the Channel basin, the structures and amplitudes of the tectonic movements remain poorly documented across the French sector of the Western Approaches. The effect of the tectonic inversion for the evolution of the “Channel River”, the major system that flowed into the English Channel during the Plio-Quaternary eustatic lowstands, also needs to be clarified. Its drainage basin was larger than the present-day English Channel and constituted the source of terrigenous fluxes of the Armorican and Celtic deep sea fans. A lack of high-resolution seismic data motivated the implementation of the GEOMOC and GEOBREST cruises, whose main results are presented in this paper. The new observations highlight the diachronism and the contrast in amplitudes of the deformations involved in the inversion of the French Western Approaches. The tectonic inversion can be described in two stages: a paroxysmal Paleogene stage including two episodes, Eocene (probably Ypresian) and Oligocene, and a more moderate Neogene stage subdivided into Miocene and Pliocene episodes, driven by the reactivation of the same faults. The deformations along the North Iroise fault (NIF) located at the termination of the Medio-Manche fault produced forced folds in the sedimentary cover above the deeper faults. The tectonic inversion generated uplift of about 700 m of the mid-continental shelf south of the NIF. The isochron map of the reflectors bounding the identified seismic sequences clearly demonstrates a major structural control on the geometry of the Neogene deposits. First, the uplift of the eastern part of the Iroise basin during the upper Miocene favoured the onset of a broad submarine delta system that developed towards the subsiding NW outer shelf. The later evolution of the ’palaeovalley’ network corresponding to the western termination of the “Channel River” exhibits a ’bayonet’ pattern marked by a zigzagging pattern of valleys, with alternating segments orientated N040oE and N070oE, controlled by Neogene faulting. The palaeovalley network could have begun during Reurevian or Pre-Tiglian sea-level lowstands, which exposed the entire shelf below the shelf edge. The amplitude of the sea-level fall is assumed to have been magnified by uplift of the Iroise basin, followed by later tilting of the outer shelf, as observed in many other examples documented along the North Atlantic margins.

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Sweet, Michael L., Gwladys T. Gaillot, Gwenael Jouet, Tammy M. Rittenour, Samuel Toucanne, Tania Marsset, and Michael D. Blum. "Sediment routing from shelf to basin floor in the Quaternary Golo System of Eastern Corsica, France, western Mediterranean Sea." GSA Bulletin 132, no. 5-6 (October 29, 2019): 1217–34. http://dx.doi.org/10.1130/b35181.1.

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Abstract How and when sediment moves from shallow marine to deep-water environments is an important and poorly understood control on basin-scale sediment dispersal patterns, the evolution of continental margins, and hydrocarbon exploration in deep-water basins. The Golo River (Eastern Corsica, France), its delta, canyons, and fans provide a unique opportunity to study sediment routing from source to sink in a relatively compact depositional system. We studied this system using an array of high-frequency seismic data, multi-beam bathymetry, and five cores for lithology and age control. Movement of sediment to deep water was controlled by interactions between the Golo River, the Golo Delta, and shelf-penetrating submarine canyons. Sediment moved to deep water when lobes of the Golo Delta prograded to the heads of these canyons, or when the Golo River itself flowed directly into one of them. Sand accumulated in canyons, deep-water channels, and submarine fans during glacial periods of low sea level, while mud was deposited throughout the slope, in the relatively short reach of leveed-confined channels, and in the mud-rich fringes around the sandy fans. During interglacial periods of high sea level, the basin was blanketed by mud-rich deposits up to 10 m thick interbedded with distinctive carbonate-rich sediments. Deposition rates in the basin ranged from 0.07 m/ka to 0.59 m/ka over the last 450 ka. Mud deposition rates remained relatively constant at ∼0.16 m/ka during all time periods, while sand deposition only happened during glacial periods of low sea level with an average rate of 0.24 m/ka. In addition to sea-level controls on sediment delivery, avulsions of the Golo River and its deltaic lobes preferentially routed sediment down either the North or South Golo canyons. Thus, while the larger, sequence-scale architecture of the basin is controlled by allogenic sea level forcing, millennial-scale autogenic processes operating on the shelf and in deep water shaped the distribution of sand and mud, and the internal geometry of the deltas and submarine fans that they fed. While some aspects of the Golo system are characteristic of steep, tectonically active margins, others such as the nature of connections between rivers and shelf-penetrating submarine canyons are observed in most margins with active submarine fans regardless of their tectonic setting.

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Pickering, K. T., and J. Corregidor. "Mass-Transport Complexes (MTCs) and Tectonic Control on Basin-Floor Submarine Fans, Middle Eocene, South Spanish Pyrenees." Journal of Sedimentary Research 75, no. 5 (September 1, 2005): 761–83. http://dx.doi.org/10.2110/jsr.2005.062.

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Pickering, Kevin T., and Jordi Corregidor. "Mass transport complexes and tectonic control on confined basin-floor submarine fans, Middle Eocene, south Spanish Pyrenees." Geological Society, London, Special Publications 244, no. 1 (2005): 51–74. http://dx.doi.org/10.1144/gsl.sp.2005.244.01.04.

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Malherbe, Hanlie, Michael Gebel, Stephan Pauleit, and Carsten Lorz. "Land Use Pollution Potential of Water Sources Along the Southern Coast of South Africa." Change and Adaptation in Socio-Ecological Systems 4, no. 1 (September 1, 2018): 7–20. http://dx.doi.org/10.1515/cass-2018-0002.

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AbstractSince the 1990’s, the groundwater quality along the southern coast of the Western Cape Province of South Africa has been affected by increasing land use activities. Groundwater resources have become increasingly important in terms of providing good quality water. Polluted coastal groundwater as a source of submarine groundwater discharge also affects the quality of coastal water. For this study, land use activities causing groundwater pollution and areas at particular risk were identified. An assessment approach linking land use/land cover, groundwater and submarine groundwater discharge on a meso-scale was developed and the methods applied to two study regions along the southern coastal area. Dryland and irrigated crop cultivation, and urbanized areas are subject to a “high” and “very high” risk of groundwater nitrogen pollution. Application of fertilizer must be revised to ensure minimal effects on groundwater. Practice of agricultural activities at locations which are not suited to the environment’s physical conditions must be reconsidered. Informal urban development may contribute to groundwater nitrogen pollution due to poor waste water disposal. Groundwater monitoring in areas at risk of nitrogen pollution is recommended. Land use activities in the submarine groundwater discharge contribution areas was not found to have major effects on coastal water.

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VAKALAS, J., G. ANANIADIS, J. MPOURLOKAS, D. POULIMENOS, K. GETSOS, G. PANTOPOULOS, P. AVRAMIDIS, A. ZELILIDIS, and N. KONTOPOULOS. "Palaeocurrent directions as an indicator of Pindos foreland evolution (central and southern part), Western Greece." Bulletin of the Geological Society of Greece 34, no. 2 (August 1, 2018): 785. http://dx.doi.org/10.12681/bgsg.17701.

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In order to estimate the palaeoflow direction of the submarine fans, deposited in the Internal Ionian subbasin of the Pindos Foreland, fifty-one positions along the sub-basin were selected and measurements of palaeocurrents indicators such as flute and groove marks were taken. In the studied area the main palaeoflow direction of turbidites was axial, from south to north in the southern part, and from north to south in the northern part. A minor westward palaeoflow direction is also present. These palaeoflow directions were influenced mainly by the regional tectonic activity, such as internal thrusting (Gavrovo Thrust) and differential activity of the Pindos Thrust which subdivided Pindos foreland into narrow linear sub-basins.

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Leat, Philip T., and Teal R. Riley. "Chapter 3.1a Antarctic Peninsula and South Shetland Islands: volcanology." Geological Society, London, Memoirs 55, no. 1 (2021): 185–212. http://dx.doi.org/10.1144/m55-2018-52.

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AbstractThe voluminous continental margin volcanic arc of the Antarctic Peninsula is one of the major tectonic features of West Antarctica. It extends from the Trinity Peninsula and the South Shetland Islands in the north to Alexander Island and Palmer Land in the south, a distance ofc.1300 km, and was related to east-directed subduction beneath the continental margin. Thicknesses of exposed volcanic rocks are up toc.1.5 km, and the terrain is highly dissected by erosion and heavily glacierized. The arc was active from Late Jurassic or Early Cretaceous times until the Early Miocene, a period of climate cooling from subtropical to glacial. The migration of the volcanic axis was towards the trench over time along most of the length of the arc. Early volcanism was commonly submarine but most of the volcanism was subaerial. Basaltic–andesitic stratocones and large silicic composite volcanoes with calderas can be identified. Other rock associations include volcaniclastic fans, distal tuff accumulations, coastal wetlands and glacio-marine eruptions.Other groups of volcanic rocks of Jurassic age in Alexander Island comprise accreted oceanic basalts within an accretionary complex and volcanic rocks erupted within a rift basin along the continental margin that apparently predate subduction.

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Hodgson, D. M., S. S. Flint, D. Hodgetts, N. J. Drinkwater, E. P. Johannessen, and S. M. Luthi. "Stratigraphic Evolution of Fine-Grained Submarine Fan Systems, Tanqua Depocenter, Karoo Basin, South Africa." Journal of Sedimentary Research 76, no. 1 (January 1, 2006): 20–40. http://dx.doi.org/10.2110/jsr.2006.03.

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Moyo, Talent, Simeon E. H. Davies, and E. Joubert. "Corporate social responsibility and organisational performance of a professional football club in South Africa." Corporate Ownership and Control 13, no. 1 (2015): 605–13. http://dx.doi.org/10.22495/cocv13i1c5p8.

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This research investigated the relationship between Corporate Social Responsibility (CSR) and organisational performance at Ajax Cape Town FC a professional football club in the South African Premier Soccer League (PSL). The data collected suggested that Ajax Cape Town FC employed CSR initiatives and consequently enjoyed various benefits from these activities. The CSR activities facilitated access to the club’s target market, developed and improved mutually beneficial relations with the community and consequently Ajax Cape Town FC experienced increased trust, a positive brand image and stronger loyalty from their fans. The outcomes of this study provide an insight into a South African professional football club and demonstrate how CSR initiatives can be used to successfully improve organisational performance.

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Jethro, Duane. "Vuvuzela Magic." African Diaspora 7, no. 2 (2014): 177–204. http://dx.doi.org/10.1163/18725465-00702003.

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During the FIFA 2010 World Cup in South Africa, a mass-produced, plastic football supporters’ horn known as the vuvuzela attracted worldwide fame and infamy. This article discusses the vuvuzela’s construction as a material and sonorous register of ‘African’ and ‘South African’ cultural distinctiveness. Specifically, it discusses the production, circulation and consumption of its ‘African’ cultural significance as a heritage form. It outlines the contested political and ideological economy – involving the South African state and football officials, FIFA, a local manufacturer, indigenous groups and football fans – through which the instrument travelled. Demonstrating the instrument’s circulation through this network, the article shows how the construction and authentication of the vuvuzela materially and sonically staged the negotiation of notions of ‘Africanness’ and ‘South Africanness’, as well as their complex relationship in post-apartheid South Africa, during the tournament.

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González-Bonorino, Gustavo. "Early development and flysch sedimentation in Ordovician Taconic foreland basin, west-central Newfoundland." Canadian Journal of Earth Sciences 27, no. 9 (September 1, 1990): 1247–57. http://dx.doi.org/10.1139/e90-133.

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During the Early to Late Ordovician the Taconic foredeep in west-central Newfoundland evolved from an underfilled to an overfilled state in response to cratonward advance, thickening, and erosion of the Taconic Orogen. Early orogen-derived sediment in the foreland basin consisted of middle(?) to lake Arenigian deep-water mudstones that accumulated on an inner (craton-facing) slope prism (uppermost parts of Shallow Bay and Green Point formations and correlative units). These deposits are interbedded with and overlie passive-margin slope sediments. In the middle Arenigian to early Llanvirnian, sand from the orogen formed several small, sand-rich submarine fans (Lower Head Formation and correlative units) on the lower reaches of the inner slope and basin plain. The fans may have been fed by closely spaced rivers draining the orogen, as presently occurs in western South America. Only proximal portions of these fans are now exposed. The flysch basin was narrow, constricted by the inner slope and the passive-margin slope, and located a short distance seaward from the buried hingeline of the proto-North American craton. As the orogen thickened sufficiently to override the crustal ramp, the carbonate shelf on the craton drowned, clastic depocentres migrated onto the foundered craton, and a thicker flysch (Mainland Sandstone) accumulated in Llanvirnian-Llandeilian time. In the Caradocian the foreland basin was overfilled with shallow-marine terrigenous sediments (Long Point Formation). Regional flysch dispersal was from a St. Lawrence promontory to a Quebec reentrant.

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Andersson, P. O. D., and R. H. Worden. "Stratigraphic variations in mudstone mineral assemblages from a submarine fan-complex: Karoo Basin, South Africa." Clay Minerals 41, no. 4 (December 2006): 839–52. http://dx.doi.org/10.1180/0009855064140223.

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AbstractDespite the high-grade diagenesis experienced by the Skoorsteenberg Formation mudstones, Tanqua Karoo basin, South Africa, geochemical data have been interpreted to reveal primary mineralogy and so help understand provenance evolution. The geochemical signatures show systematic variations related to stratigraphy. The main changes in mudstones from the lower to the upper part of the section include: (1) an increase in the feldspar content of the primary sediment and a decrease in the content of Al-rich clay (probably dioctahedral smectite); (2) a decrease in the degree of chemical weathering of the sediment, representing a change to a dryer and/or cooler climate; (3) an increase in TiO2/Al2O3 representing increasing mafic sources; (4) an increase in CaO/(K2O+CaO) also possibly representing increasing mafic sources. Mass flux and differential diagenesis are unlikely to be responsible for the depth-related changes since the rocks have undergone the same degree of high-grade diagenesis and the mudstones are interrupted by other lithologies, so disturbing any sort of diffusion gradient. These variations could plausibly be the result of one or more of differential weathering, evolving provenance characteristics or variable hydrodynamic fractionation of the sediment. The ratio of Zr/Y, a possible indicator of hydrodynamic fractionation, increases only slightly and irregularly up-section. There is no relationship between the silica content, representative of the quartz-silt content of the sediment, and TiO2/Al2O3 showing that the amount of quartz, and so the degree of hydrodynamic fractionation, has not controlled mudstone geochemistry. The stratigraphic increase in feldspar content, the decrease in Al-rich clay content and increase of both TiO2/Al2O3 and CaO/(K2O+CaO) must be due to a combination of marginally evolving provenance characteristics (more mafic and felsic rocks exposed to weathering with time) and changes in the degree of rock weathering (less chemical weathering with time).

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Andersson, P. O. D., R. H. Worden, D. M. Hodgson, and S. Flint. "Provenance evolution and chemostratigraphy of a Palaeozoic submarine fan-complex: Tanqua Karoo Basin, South Africa." Marine and Petroleum Geology 21, no. 5 (May 2004): 555–77. http://dx.doi.org/10.1016/j.marpetgeo.2004.01.004.

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McDougall, N., P. J. Brenchley, J. A. Rebelo, and M. Romano. "Fans and fan deltas – precursors to the Armorican Quartzite (Ordovician) in western Iberia." Geological Magazine 124, no. 4 (July 1987): 347–59. http://dx.doi.org/10.1017/s0016756800016678.

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AbstractThe Armorican Quartzite (Lower Ordovician) is a very extensive sandstone body found throughout a large part of Iberia and Brittany; similar quartzites are present in north Africa and elsewhere. In Iberia it generally lies unconformably on a thick, folded, late Precambrian to Cambrian turbidite sequence (the Complexo Xisto-Grauváquico (CXG)), but there are some places where the quartzite has a conformable relationship with the underlying CXG. Where conformable the whole succession shows varied facies sequences including: (i) a regressive mud–sand sequence as a precursor to the main quartzite development, (ii) submarine fan sediments of the CXG passing up into slope and then shallow marine facies, or (iii) fluvially influenced breccio-conglomerates of a marginal fan delta passing up into shallow marine sediments.The inferred development of alluvial fans associated with fan deltas prograding into shallow marine environments implies steep slopes and the likelihood that faulting controlled some of the uplift. The mozaic pattern of differential uplift and subsidence throughout the region suggests that the CXG was affected by local block movements rather than by regional folding.The presence of upstanding blocks during the initial sedimentation of the Armorican Quartzite suggests that the quartz sand might have been derived from multiple sources dispersed throughout the area rather than from sources along a single shoreline at the margin of the depositional area.

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Noti, A., P. Tserolas, A. Maravelis, and A. Zelilidis. "THE TECTONO - STRATIGRAPHIC EVOLUTION OF PINDOS FORELAND EAST OF MESOLONGI." Bulletin of the Geological Society of Greece 50, no. 1 (July 27, 2017): 94. http://dx.doi.org/10.12681/bgsg.11705.

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Sedimetological analysis of submarine fan deposits, both north and south of Evinos River, east of Mesolongi town, showed that there are different sedimentological conditions. The southern part outcropped between Klokova and Varasova Mountains, influenced by Gavrovo thrust activity, is characterized by coarse grained inner fan deposits, and sourced both from Pindos chain and the uplifted Klokova and Varasova Mountains. Gavrovo thrust activity, took place during the sedimentation producing intrabasinal highs, changing basin geometry. In the northern part, where outer fan deposits passes upwards to inner fans, there is no obvious influence of Gavrovo thrust but mostly the influence of internal Ionian Thrust. Between the two studied areas there is a high deformed area, about 1km wide, trending parallel to the Evinos River in a ENE direction, showing that probable Evinos River flows on a strike-slip fault.

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Di Celma, C. N., R. L. Brunt, D. M. Hodgson, S. S. Flint, and J. P. Kavanagh. "Spatial and Temporal Evolution of a Permian Submarine Slope Channel-Levee System, Karoo Basin, South Africa." Journal of Sedimentary Research 81, no. 8 (July 18, 2011): 579–99. http://dx.doi.org/10.2110/jsr.2011.49.

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Hicks, Nigel, and Andrew Green. "Sedimentology and depositional architecture of a submarine delta-fan complex in the Durban Basin, South Africa." Marine and Petroleum Geology 78 (December 2016): 390–404. http://dx.doi.org/10.1016/j.marpetgeo.2016.09.032.

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Jadhav, Varsha D., and Sachin N. Deshmukh. "Twitter Intention Classification Using Bayes Approach for Cricket Test Match Played Between India and South Africa 2015." International Journal of Rough Sets and Data Analysis 4, no. 2 (April 2017): 49–62. http://dx.doi.org/10.4018/ijrsda.2017040104.

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Information retrieval and forecasting in real time is becoming the fastest and most efficient way to obtain useful knowledge of what is happening now, allowing organizations to react quickly when problem appears which help to improve their performance. There is enormous amount of data in the form of tweets. It builds data processing system that creates informative data about the cricket test matches. Using twitter data, the authors find the sentiments or polarity of fans posting tweets related to game. Polarity is given as positive, negative and neutral. The authors also analyze the feelings or emotions of people posting tweets. Emotions are given as anger, disgust, fear, joy, sadness, surprise and unknown. Machine learning algorithm (Bayes) using R technology shows the accuracy when trained with emotion data.

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Miller, L. R., and W. J. Stuart. "SEISMIC STRATIGRAPHIC EVALUATION OF A NEOCOMIAN SUBMARINE FAN SYSTEM, BROWSE BASIN, NORTH WEST SHELF." APPEA Journal 32, no. 1 (1992): 171. http://dx.doi.org/10.1071/aj91014.

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A possible submarine fan system of Valanginian age occurs in the south of the western half of Permit WA-212-P in the Browse Basin. Seismic mapping and interpretation have allowed the recognition of five seismic facies which are considered representative of this fan system.The five seismic facies are the upper-middle fan braided channel facies, the upper-middle fan braided interchannel facies, the lower fan channel facies, the lower fan sheet facies, and the lower fan lobe fringe facies. The reflections of the upper-middle braided channel fan facies are discontinuous, disrupted, convex up, low amplitude and high frequency. The interchannel facies has reflections that are concave up, continuous, low frequency and moderate to high amplitude. The lower fan channel facies are recognised by convex up, discontinuous, high frequency and low amplitude reflections. The lower fan sheet facies is noted by mounded configurations with continuous, moderate to high amplitude, moderate frequency reflections. The lower fan lobe fringe facies reflections are flat, often shingled reflections with moderate discontinuity, moderate to high amplitude and low to moderate frequency.Since no wells penetrate the submarine fan, the interpretation is based on seismic reflection configurations which are considered typical of submarine fan segments. The interpreted ancient submarine fan occurs on the basin floor adjacent to a probable ramp type margin, and manifests shape and setting consistent with known submarine fans, such as the Eocene Frigg Fan of the North Sea, and the Lower Cretaceous Barrow Group turbidites in the Carnarvon Basin.Seismic facies mapping, in conjunction with sequence stratigraphy concepts, is particularly useful in areas such as the Browse Basin where considerable marine shale sections exist with little structure, and sequences with reservoir potential continue to be a problem to locate. For instance, in Caswell-1, a well drilled in 1977 immediately north of the permit area, 200 barrels of oil flowed from thin sands within a shale sequence of Albian age. Results of this study indicate that local seismic reflection signatures may be indicative of potential sandstone reservoirs in the vicinity of the study area.

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Alber, Erdmute, and Christian Ungruhe. "Fans and states at work: a Ghanaian fan trip to the FIFA World Cup 2010 in South Africa." Soccer & Society 17, no. 1 (February 17, 2014): 18–39. http://dx.doi.org/10.1080/14660970.2014.882816.

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Green, Andrew, and Ron Uken. "Submarine landsliding and canyon evolution on the northern KwaZulu-Natal continental shelf, South Africa, SW Indian Ocean." Marine Geology 254, no. 3-4 (September 2008): 152–70. http://dx.doi.org/10.1016/j.margeo.2008.06.001.

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Yin, Shaoru, Guangfa Zhong, Yiqun Guo, and Liaoliang Wang. "Seismic stratigraphy and tectono-sedimentary framework of the Pliocene to recent Taixinan foreland basin in the northeastern continental margin, South China Sea." Interpretation 4, no. 3 (August 1, 2016): SP21—SP32. http://dx.doi.org/10.1190/int-2015-0177.1.

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The Pliocene to recent Taixinan basin is a unique foreland basin built on the northeastern part of the northern passive margin of the South China Sea (SCS). We have used multichannel seismic profiles tied to well controls from ODP Leg 184 to investigate the tectonic and sedimentary characteristics of the foreland basin. We defined three seismic sequences, dated respectively to the Pliocene (5.33–2.5 Ma), early Quaternary (2.5–1.0 Ma), and late Quaternary (1.0 Ma–present). They represent three stages of evolution of the foreland basin. We have recognized seven types of seismic facies, which are parallel-to-subparallel, progradational, fill-type, divergent mounded, wavy, lenticular, and chaotic facies, and are interpreted as hemipelagic deposits, deltas, submarine canyon fills, levees, sediment waves, submarine fans, and mass transport deposits, respectively. Seismic facies analysis indicates that sedimentation within the foreland basin has been dominated by turbidity currents and the other gravity transport processes. Tectonically, the foreland basin consists of three structural zones: an eastern wedge-top, a central foredeep, and a western forebulge zones. Different from a typical foreland basin, however, the basin extends in the northeast–southwest direction, which is oblique to the north–south-striking Taiwan orogenic zone, but parallel to the northern SCS passive margin, where the basin is hosted, suggesting that the foreland basin is significantly influenced by the development of the passive margin. In addition, the basin displays a distinctive inverted-triangle-shaped downstream-converging sediment dispersal system instead of ideal transverse or longitudinal drainage systems common in a typical foreland basin. We have suggested that the Pliocene to recent Taixinan basin is an atypical foreland basin, which was formed as a flexural response of tectonic loading by the Taiwan orogenic wedge, but strongly affected by its passive continental margin background.

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Meiswinkel, R., M. Baylis, and K. Labuschagne. "Stabling and the protection of horses from Culicoides bolitinos (Diptera: Ceratopogonidae), a recently identified vector of African horse sickness." Bulletin of Entomological Research 90, no. 6 (December 2000): 509–15. http://dx.doi.org/10.1017/s0007485300000626.

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AbstractThe stabling of horses at night reportedly offers protection from African horse sickness and the most significant vector of the disease, Culicoides imicolaKieffer, has been shown to be exophilic. In certain high-lying regions of South Africa, however, C. bolitinos Meiswinkel, may be the major vector of the disease but its entry behaviour into stables is unknown. Accordingly, in the eastern Free State province of South Africa, light trap catches of C. bolitinos inside stables and outside, were compared. Two horse-baited stables, one traditional, and one modern, were used and combinations of stable (old/new), ceiling fans (on/off) and accessibility to Culicoides (stable doors open/closed or windows gauzed/ungauzed) were investigated as treatments. A total of 111,452 Culicoides of 26 species was collected on 60 trap nights; C. bolitinos was dominant (89.1% overall) with C. imicola second in abundance (2.9%). Outside catches were greater on warmer, drier, evenings but were suppressed by high wind speeds. Catches of C. imicola inside stables with doors open, or with windows ungauzed, were less than the numbers captured outside. In contrast, more C. bolitinos were caught in open stables than outside, i.e. open structures may protect horses from the exophilic C. imicola, but may increase attack rates from the endophilic C. bolitinos. The closing of doors and the gauzing of windows, however, led to a 14-fold reduction in numbers of C. bolitinos and C. imicola entering stables. A well-gauzed ‘traditional’ stable was as effective as a closed ‘modern’stable. Ceiling fans had no suppressant effect.

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Figueiredo, J. J. P., D. M. Hodgson, S. S. Flint, and J. P. Kavanagh. "Depositional Environments and Sequence Stratigraphy of an Exhumed Permian Mudstone-Dominated Submarine Slope Succession, Karoo Basin, South Africa." Journal of Sedimentary Research 80, no. 1 (January 1, 2010): 97–118. http://dx.doi.org/10.2110/jsr.2010.002.

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Pringle, J. K., R. L. Brunt, D. M. Hodgson, and S. S. Flint. "Capturing stratigraphic and sedimentological complexity from submarine channel complex outcrops to digital 3D models, Karoo Basin, South Africa." Petroleum Geoscience 16, no. 4 (October 20, 2010): 307–30. http://dx.doi.org/10.1144/1354-079309-028.

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29

Cornell, D. H., S. S. Schütte, and B. L. Eglington. "The Ongeluk basaltic andesite formation in Griqualand West, South Africa: submarine alteration in a 2222 Ma proterozoic sea." Precambrian Research 79, no. 1-2 (July 1996): 101–23. http://dx.doi.org/10.1016/0301-9268(95)00090-9.

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30

Krastel, S., W. Li, M. Urlaub, A. Georgiopoulou, R. B. Wynn, T. Schwenk, C. Stevenson, and P. Feldens. "Mass wasting along the NW African continental margin." Geological Society, London, Special Publications 477, no. 1 (May 23, 2018): 151–67. http://dx.doi.org/10.1144/sp477.36.

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AbstractThe NW African continental margin is well known for the occurrence of large-scale but infrequent submarine landslides. The aim of this paper is to synthesize the current knowledge on submarine mass wasting off NW Africa with a special focus on the distribution and timing of large landslides. The described area reaches from southern Senegal to the Agadir Canyon. The largest landslides from south to north are the Dakar Slide, the Mauritania Slide, the Cap Blanc Slide, the Sahara Slide and the Agadir Slide. Volumes of individual slides reach several hundreds of cubic kilometres; run-outs are up to 900 km. In addition, giant volcanic debris avalanches are widespread on the flanks of the Canary Islands. All headwall areas are complex with clear indications of multiple failures. The most prominent similarity between all investigated landsides is the existence of widespread glide planes that follow the stratigraphy, which points to weak layers as most important preconditioning factor for the failures. Landslides with volumes larger than 100 m3 are close to being evenly distributed over time, contradicting previous suggestions that landslides off NW Africa occur at periods of low or rising sea level. The risk associated with the landslides off NW Africa, however, is relatively low due to their long recurrence rates.

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Rathbone, P. A., D. J. Livingstone, and M. M. Calder. "Surveys monitoring the sea and beaches in the vicinity of Durban, South Africa: a case study." Water Science and Technology 38, no. 12 (December 1, 1998): 163–70. http://dx.doi.org/10.2166/wst.1998.0531.

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A microbiological surveillance programme was initiated in Durban, South Africa, to provide an objective assessment of changes in the local seawater quality before and after the commissioning of two submarine outfalls in 1969 and has been ongoing until the present day. A classification system including Escherichia coli I, helminthic parasite ova, pathogenic staphylococci, salmonellae, shigellae, and salinity was used. This system, functioning as an audit, has proved useful in detecting problem areas which may have passed unnoticed in the routine E coli I assessments performed by the Durban Municipality. The salient features that have manifested themselves are (a) alterations in the seawater quality have been shown to be invariably a consequence of changes effected upon the shore or meteorological events and (b) that measuring more than one indicator of water quality, plus the use of salinity as a physical parameter for assessing the dilution or impairment of pristine seawater, has proved valuable.

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32

E. Davis. Jr., William. "Heard Island: Southern Ocean Sentinel." Pacific Conservation Biology 13, no. 2 (2007): 145. http://dx.doi.org/10.1071/pc070145.

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Heard Island is one of the most remote places on earth. It is of volcanic origin (and currently volcanically active) on the submarine Kerguelen Plateau in the Southern Ocean, roughly 4 000 km south-west of Australia, 1 500 km from Antarctica, 3 750 km from Africa, and 7 500 km from India. The island is 367 km2 in area at latitude 53�S, south of the Antarctic Polar Front (Antarctic Convergence), is 70% covered with glaciers, and has a geologic, biologic and human history of substantial interest. Because of its remoteness, relative recent discovery (1853), and infrequent human visitation, it is pristine with no human-introduced plants or mammals.

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33

Luthi, Stefan M., David M. Hodgson, Cees R. Geel, Stephen S. Flint, Jan Willem Goedbloed, Nicholas J. Drinkwater, and Erik P. Johannessen. "Contribution of research borehole data to modelling fine-grained turbidite reservoir analogues, Permian Tanqua–Karoo basin-floor fans (South Africa)." Petroleum Geoscience 12, no. 2 (May 2006): 175–90. http://dx.doi.org/10.1144/1354-079305-693.

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34

Matshonisa Seeletse, Solly. "Demarketing strategy to develop perceived product reputation: applications in three distinct environments." Problems and Perspectives in Management 14, no. 4 (December 23, 2016): 230–35. http://dx.doi.org/10.21511/ppm.14(4-1).2016.12.

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This paper illustrates ‘demarketing’ and its uses to improve product image in the customers’ viewpoints. Three events stimulated the investigations. First, a leading political party lost local municipal elections in a large South Africa metropolitan. Second, a reputable soccer club lost many fans to other teams. Thirdly, a local confectionary lost clients. Investigations took place in the three settings (soccer, politics and confectionary business). The respondents were known clients or fans of the original entities, who had defected to rivals. A questionnaire was used to collect data. The entities apparently ignored the services promised to clients. Despite them being dissimilar entities, similarities occurred in the way they lost favor with their clients. The study identified demarketing as a common factor. Demarketing was applied by the rivals, and was imbedded in their policies. People and entity representatives’ used demarketing strategies to lure clients. The paper recommends that demarketing should be applied to control the market. Also, it recommends that agile competitors should augment normal marketing with demarketing to optimize marketing results. Keywords: demarketing strategy, demand, perception, product quality. JEL Classification: D47, M14, M31, M37

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35

Green, Andrew. "Submarine canyons associated with alternating sediment starvation and shelf-edge wedge development: Northern KwaZulu-Natal continental margin, South Africa." Marine Geology 284, no. 1-4 (June 2011): 114–26. http://dx.doi.org/10.1016/j.margeo.2011.03.011.

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36

Spychala, Y. T., D. M. Hodgson, S. S. Flint, and N. P. Mountney. "Constraining the sedimentology and stratigraphy of submarine intraslope lobe deposits using exhumed examples from the Karoo Basin, South Africa." Sedimentary Geology 322 (June 2015): 67–81. http://dx.doi.org/10.1016/j.sedgeo.2015.03.013.

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OLIVEIRA, CARLOS M. M., DAVID M. HODGSON, and STEPHEN S. FLINT. "Aseismic controls onin situsoft-sediment deformation processes and products in submarine slope deposits of the Karoo Basin, South Africa." Sedimentology 56, no. 5 (August 2009): 1201–25. http://dx.doi.org/10.1111/j.1365-3091.2008.01029.x.

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38

Klemd, R., K. J. Maiden, M. Okrusch, and P. Richter. "Geochemistry of the Matchless metamorphosed massive sulfide deposit, South West Africa/Namibia; wall-rock alteration during submarine ore-forming processes." Economic Geology 84, no. 3 (May 1, 1989): 603–17. http://dx.doi.org/10.2113/gsecongeo.84.3.603.

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39

Van Der MERWE, WILLEM C., DAVID M. HODGSON, and STEPHEN S. FLINT. "Origin and terminal architecture of a submarine slide: a case study from the Permian Vischkuil Formation, Karoo Basin, South Africa." Sedimentology 58, no. 7 (July 21, 2011): 2012–38. http://dx.doi.org/10.1111/j.1365-3091.2011.01249.x.

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40

Dann, Jesse. "Vesicular komatiites, 3.5-Ga Komati Formation, Barberton Greenstone Belt, South Africa: inflation of submarine lavas and origin of spinifex zones." Bulletin of Volcanology 63, no. 7 (November 1, 2001): 462–81. http://dx.doi.org/10.1007/s004450100164.

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41

Cristian, Réka M. "Transnational Encounters." Acta Hispanica, no. II (October 4, 2020): 663–71. http://dx.doi.org/10.14232/actahisp.2020.0.663-671.

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The text focuses on a series of transnational flows and polylocal agencies marking the art of the American folk musician and performer Sixto Rodriguez. After issuing two albums in the seventies, he was quickly forgotten in the USA but luckily not outside of it. His first album, Cold Fact (1970), became the unofficial anthem for the anti-apartheid movement in South Africa in the seventies and the performer was paradoxically ‘rediscovered’ due to a hoax with the help of enduring South-African, Botswanan, Zimbabwean, Australian and New Zealander fans and through the research of the Swedish-Algerian filmmaker Malik Bendjelloul, who made and directed Searching for Sugarman (2012), an Oscar-winning documentary film. The quest for Rodriguez’s global itineraries still goes on through his official webpage and the release of a book in 2015 with performer-activist Rodriguez becoming in the context of global discourses and Deep Maps strategy a transnational figure rather than just an American singer.

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42

Gao, Nanan, Changsong Lin, Kenneth Eriksson, Zhongtao Zhang, Da Gao, Bo Zhang, Liangfeng Shu, and An Wei. "Sequence architecture and depositional evolution of Eocene to Oligocene, synrift to early postrift strata in the Baiyun Sag, South China Sea." Interpretation 7, no. 2 (May 1, 2019): T309—T329. http://dx.doi.org/10.1190/int-2018-0055.1.

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The Pearl River Mouth Basin (PRMB), located on the northern continental margin of the South China Sea, underwent a complex evolution during the Paleogene. We have focused on the Baiyun Sag in the PRMB with the goal of constructing the architecture and depositional evolution of the Eocene–Early Oligocene synrift stage to the Late Oligocene early postrift stage of basin evolution. Based on analysis of 3D seismic data complemented by well logs and cores, the Paleogene basin fills can be classified into three composite sequences bounded by regional unconformities and 14 sequences bounded by local unconformities. We identify seismic facies on the basis of different internal reflection configurations, external shapes, and contact relationships. The distribution of seismic facies and lithologies interpreted from gamma-ray curves reveal that the synrift basin fill consists mainly of fan delta deposits adjacent to the southern fault scarp, braid delta deposits on the adjacent hanging-wall blocks, and lacustrine mudstones and sublacustrine fan deposits in the center of the basin. The overlying early postrift stage is dominated by shelf and shelf-slope environments, with widespread developed southward-prograding deltas and submarine fans. Tectonics is the principal controlling factor on the development and distribution of depositional systems during the synrift stage. In contrast, sea-level changes superimposed on long-term subsidence related to thermal cooling determined the stacking patterns of sequences during the postrift stage. The results provide new insights on synrift and early postrift tectonics and sedimentation patterns along an evolving passive margin.

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Micallef, Aaron, Aggeliki Georgiopoulou, Andrew Green, and Vittorio Maselli. "Impact of sea-level fluctuations on the sedimentation patterns of the SE African margin: implications for slope instability." Geological Society, London, Special Publications 500, no. 1 (December 19, 2019): 267–76. http://dx.doi.org/10.1144/sp500-2019-172.

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AbstractThe sheared-passive margin offshore Durban (South Africa) is characterized by a narrow continental shelf and steep slope hosting numerous submarine canyons. Supply of sediment to the margin is predominantly terrigenous, dominated by discharge from several short but fast-flowing rivers. International Ocean Discovery Program Expedition 361 provides a unique opportunity to investigate the role of sea-level fluctuations on the sedimentation patterns and slope instability along the South African margin. We analysed >300 sediment samples and downcore variations in P-wave, magnetic susceptibility, bioturbation intensity and bulk density from site U1474, as well as regional seismic reflection profiles to: (1) document an increase in sand input since the Mid-Pliocene; (2) associate this change to a drop in sea-level and extension of subaerial drainage systems towards the shelf-edge; (3) demonstrate that slope instability has played a key role in the evolution of the South Africa margin facing the Natal Valley. Furthermore, we highlight how the widespread occurrence of failure events reflects the tectonic control on the morphology of the shelf and slope, as well as bottom-current scour and instability of fan complexes. This information is important to improve hazard assessment in a populated coastal region with growing offshore hydrocarbon activities.

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Foster, Ian D. L., John Boardman, Adrian L. Collins, Ruth Copeland-Phillips, Nikolaus J. Kuhn, Tim M. Mighall, Simon Pulley, and Kate M. Rowntree. "The potential for gamma-emitting radionuclides to contribute to an understanding of erosion processes in South Africa." Proceedings of the International Association of Hydrological Sciences 375 (March 3, 2017): 29–34. http://dx.doi.org/10.5194/piahs-375-29-2017.

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Abstract. Several research projects undertaken by the authors and others over the last 14 years have used fallout and geogenic radionuclides for understanding erosion processes and sediment yield dynamics in South Africa over the last 100–200 years as European settlers colonised the interior plains and plateaux of the country and imported new livestock and farming techniques to the region. These projects have used two fallout radionuclides (210Pb and 137Cs) to date sediments accumulating in reservoirs, farm dams, wetlands, alluvial fans and floodouts and have used other fallout nuclides (7Be) and long-lived geogenic radionuclides (e.g. 40K, 235U) as part of a composite fingerprint exploring contemporary sediment sources and changes to sources through time. While successful in many parts of the world, applying these techniques in Southern Africa has posed a number of challenges often not encountered elsewhere. Here we explore some of the benefits and challenges in using gamma-emitting radionuclides, especially 137Cs, in these landscapes. Benefits include the potential for discriminating gully sidewall from topsoil sources, which has helped to identify contemporary gully systems as sediment conduits, rather than sources, and for providing a time-synchronous marker horizon in a range of sedimentary environments that has helped to develop robust chronologies. Challenges include the spatial variability in soil cover on steep rocky hillslopes, which is likely to challenge assumptions about the uniformity of initial fallout nuclide distribution, the paucity of stable (non-eroding) sites in order to estimate atmospheric fallout inventories, and the limited success of 210Pb dating in some rapidly accumulating high altitude catchments where sediments often comprise significant amounts of sand and gravel. Despite these challenges we present evidence suggesting that the use of gamma-emitting radionuclides can make a significant contribution to our understanding of erosion processes and sediment yield dynamics. Future research highlighted in the conclusion will try to address current challenges and outline new projects established to address them more fully.

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Porter, Sean N., and Michael H. Schleyer. "Environmental Variation and How its Spatial Structure Influences the Cross-Shelf Distribution of High-Latitude Coral Communities in South Africa." Diversity 11, no. 4 (April 10, 2019): 57. http://dx.doi.org/10.3390/d11040057.

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Coral communities display spatial patterns. These patterns can manifest along a coastline as well as across the continental shelf due to ecological interactions and environmental gradients. Several abiotic surrogates for environmental variables are hypothesised to structure high-latitude coral communities in South Africa along and across its narrow shelf and were investigated using a correlative approach that considered spatial autocorrelation. Surveys of sessile communities were conducted on 17 reefs and related to depth, distance to high tide, distance to the continental shelf edge and to submarine canyons. All four environmental variables were found to correlate significantly with community composition, even after the effects of space were removed. The environmental variables accounted for 13% of the variation in communities; 77% of this variation was spatially structured. Spatially structured environmental variation unrelated to the environmental variables accounted for 39% of the community variation. The Northern Reef Complex appears to be less affected by oceanic factors and may undergo less temperature variability than the Central and Southern Complexes; the first is mentioned because it had the lowest canyon effect and was furthest from the continental shelf, whilst the latter complexes had the highest canyon effects and were closest to the shelf edge. These characteristics may be responsible for the spatial differences in the coral communities.

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46

Hodgson, D. M., H. L. Brooks, A. Ortiz-Karpf, Y. Spychala, D. R. Lee, and C. A. L. Jackson. "Entrainment and abrasion of megaclasts during submarine landsliding and their impact on flow behaviour." Geological Society, London, Special Publications 477, no. 1 (March 28, 2018): 223–40. http://dx.doi.org/10.1144/sp477.26.

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AbstractMany mass transport complexes (MTCs) contain up to kilometre-scale (mega)clasts encased in a debritic matrix. Although many megaclasts are sourced from the headwall areas, the irregular basal shear surfaces of many MTCs indicate that megaclast entrainment during the passage of flows into the deeper basin is also common. However, the mechanisms responsible for the entrainment of large blocks of substrate, and their influence on the longitudinal behaviour of the associated flows, have not been widely considered. We present examples of megaclasts from exhumed MTCs (the Neuquén Basin, Argentina and the Karoo Basin, South Africa) and MTCs imaged in three-dimensional seismic reflection data (Magdalena Fan, offshore Colombia and Santos Basin, offshore Brazil) to investigate these process–product interactions. We show that highly sheared basal surfaces are well developed in distal locations, sometimes extending beyond their associated deposit. This points to deformation and weakening of the substrate ahead of the flow, suggesting that preconditioning of the substrate by distributed shear ahead of, and to the side of, a mass flow could result in the entrainment of large fragments. An improved understanding of the interactions between flow evolution, seabed topography, and the entrainment and abrasion of megaclasts will help to refine estimates of run-out distances, and therefore the geohazard potential of submarine landslides.

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47

McGlashan, J. E., and D. C. Macleod. "The Effect of Sewage Sludge Disposal to Sea through Pipelines Previously Discharging only Settled Effluent." Water Science and Technology 18, no. 11 (November 1, 1986): 93–104. http://dx.doi.org/10.2166/wst.1986.0145.

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The City of Durban has two submarine outfall sewers designed for the disposal of approximately 365 000 m3/d of domestic and industrial effluents. Until recently these outfall sewers were only permitted to discharge settled effluents, the resultant sludge having to be treated and disposed of on land in the one instance and incinerated in the other. As the result of a two year programme of research the city has been permitted to discharge settled effluent from both outfalls to which the underflow from the sedimentation basins has been reintroduced. Retention of the sedimentation basins has permitted effective removal of floatable material. The pipelines were operated during the research period by discharging only settled effluent from the one whilst from the other the discharge consisted of the settled effluent stream to which the sludge had been reintroduced. Halfway through the programme the roles of the two pipelines were reversed. This paper briefly reviews marine disposal in South Africa, the Durban submarine outfalls, the events which preceded the research project, the design of the research programme and the results of the study in terms of bacteriological, biological and chemical monitoring, current measurements in the immediate vicinity of the pipelines and dilution calculations with the aid of more rigorous mathematical treatment.

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48

Lajeunesse, Patrick, and Michel Allard. "The Nastapoka drift belt, eastern Hudson Bay: implications of a stillstand of the QuebecLabrador ice margin in the Tyrrell Sea at 8 ka BP." Canadian Journal of Earth Sciences 40, no. 1 (January 1, 2003): 65–76. http://dx.doi.org/10.1139/e02-085.

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During deglaciation of eastern Hudson Bay, the western margin of the QuébecLabrador sector of the Laurentide Ice Sheet came to a stillstand about 8 14C ka BP along the Nastapoka Hills, a series of topographic highs along the bay. These hills are the northward continuation of the eastern Hudson Bay cuesta system. It left a drift belt consisting of ice-contact submarine fans along the western slopes of the hills, small frontal moraines on hilltops, and grounding-line deposits on sills between the hills. Geomorphological, sedimentary, and radiometric evidence suggest that the stillstand responsible for deposition of the Nastapoka drift belt was either entirely or partly synchronous with the deposition of the Sakami moraine farther south. There was a period when these two morainic systems marked a continuous ice margin. These stillstands occurred due to reduction of ablation at the ice margin. In the Nastapoka Hills, ablation slowed down when the ice margin was anchored on higher relief and stood at a regional break of slope that grounded the ice margin and reduced water depth at the ice terminus, therefore, putting an end to intensive calving. In eastern James Bay and southeastern Hudson Bay, stabilization of the ice margin was caused by a reequilibrium of the ice terminus after a rapid drop of water level due to the drainage of Glacial Lake Ojibway. The new data improves the resolution of the position ice margin in eastern Hudson Bay at 8 ka BP.

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BERNAL, M. C., S. D. CAIRNS, P. E. PENCHASZADEH, and D. LAURETTA. "Stylasterids (Hydrozoa: Stylasteridae) from Mar del Plata submarine canyon and adjacent area (southwestern Atlantic), with a key to the species off Argentina." Zootaxa 4969, no. 3 (May 12, 2021): 401–52. http://dx.doi.org/10.11646/zootaxa.4969.3.1.

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The Argentine continental margin is a poorly explored area as regards its benthic biodiversity. Few works have been made near the Brazil-Malvinas confluence (around 38° S) regarding corals, especially in deep waters (over 1000 m). Hitherto 17 species of stylasterids are known from southwestern Atlantic (SWA) off Argentina. Fourteen species of stylasterids collected from the Mar del Plata submarine canyon and adjacent area in years 2012 and 2013 at depths between 800 and 2200 m are discussed, including the descriptions of 13 of them. The geographic distribution of six species and bathymetric range of occurrence of two species are broadened in this work. Stations where most specimens were collected are located in areas where sedimentation is known to be scarce. Species in common between the study area and the Antarctic region, south of Chile, South Africa, New Zealand and New Caledonia suggest the Circumpolar Antarctic Current and the Malvinas Current are the means for dispersion. A key of identification of all stylasterid species off Argentina is included.

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Wiles, Errol, Andrew Green, Mike Watkeys, Wilfred Jokat, and Ralph Krocker. "The evolution of the Tugela canyon and submarine fan: A complex interaction between margin erosion and bottom current sweeping, southwest Indian Ocean, South Africa." Marine and Petroleum Geology 44 (June 2013): 60–70. http://dx.doi.org/10.1016/j.marpetgeo.2013.03.012.

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Journal articles on the topic 'Submarine fans – South Africa'

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