Karoo shale gas baseline research program gets on the way at nmmu 20140219 this project recognises the need for independent robust scientificbased advice to objectively evaluate costbenefit equations, in light of potential bias andor sectional interests related to potential shale gas exploitation in the karoo. This book describes the latest research on the geological, geochemical, geochronological, biological, and geomorphic evolution of the unique and relatively pristine landscape of the cape mountains and the karoo basin, a region in south africa that is currently being targeted for shale gas. We believe that the environmentally sensitive karoo can be protected even if it becomes a national energy resource. Anatomy of a mixedinfluence shelf edge delta, karoo basin. Report on a field visit to exposures in the kalahari. If enough natural gas is found, it could provide south africa with a stable, cleanerburning energy supply for power generation and economic activity for decades. A revision of the ovuliferous fructifications of glossopterids from the permian of south africa. Studies of the effects of mass extinctions on ancient ecosystems have focused on changes in taxic diversity, morphological disparity, abundance, behaviour and resource availability as key. Fossils from the dwyka group in the warmbad basin in southernnamibiafig. Jul 14, 2017 unpacking the issues around fracking in south africa. Submarine mass movement deposits exposed in the vischkuil formation, laingsburg karoo basin, south africa, provide a rare opportunity to analyse and interpret their emplacement history and deformation processes at a scale comparable to seismic examples. The larger megatheropod tracks are 57 cm long and have no.
Given the importance of the karoo system and kalahari group aquifers it is. When and how did the terrestrial midpermian mass extinction. Karoo basin, biostratigraphy, palaeoenvironment, basin development. Shell has applied for rights to explore for natural gas in the karoo. Major portions of the karoo basin have igneous sill intrusions and complex geology, which may affect the quality of the shale resources and create significant exploration risk in pursuing shale plays in the prospective area. Evolution, architecture and hierarchy of distributary deep. This latter area, referred to as the huab basin in the. Depositional environments and stratigraphic correlation of. Predrill groundwater geochemistry in the karoo basin, south. Origin and terminal architecture of a submarine slide.
South africa karoo shale gas deposits seen less than earlier estimates. Xxxx 1 a lithostratigraphic and magnetostratigraphic framework in a geochronologic context for a purported permiantriassic boundary section at old west lootsberg pass, karoo basin. Jul 22, 2015 the existence of a concurrent tetrapod extinction event in the nonmarine karoo basin, situated thousands of kilometres from the emeishan lip, would also suggest an extinction mechanism with a global influence, such as atmospheric disruption through the release of volcanic gases and largescale contact metamorphism of biogenic rocks 11,39,41,42. The coalbearing sediments and coal seams of the karoo basin, southern africa are. Further, groundwater in the karoo basin is the primary source of both drinking and. There are virtually no sills in the basement complexes west and east of the karoo basin.
Currently the permian whitehill formation is thought to be most favourable target formation for shale gas exploration and production, owing to the high total organic content toc averaging 5%, favourable maturities ro 1 4 %, thickness 30m average. The south african portion of the ellisras basin is about 90 kilometres 56 mi from east to west and 35 kilometres 22 mi from north to south. Until recently, the karoo basin was not considered prospective for productive hydrocarbons resulting in very limited modern hydrocarbon exploration onshore in south africa. The karoo tectonic evolution of the tanganyikarukwamalawitrm zone in the east african rift. It extends east from the kalahari basin that underlies much of botswana. The karoo basins of southcentral africa preserve a record of a special time in earths history, when the pangea supercontinent reached its maximum extent during the late paleozoicearly mesozoic interval. Flintd ageological survey of alabama, tuscaloosa, al, usa. The cape and karoo basins represent two largescale episodes of intermittent subsidence and sedimentation within the interior of gondwana fig. The cape and karoo basin stratigraphy in the sw karoo. Origin and evolution of the cape mountains and karoo basin linol, b. The karoo basin in south africa offers an ideal study area to evaluate these processes because the region is targeted for shale gas extraction in the near future, but has only been minimally developed for conventional energy extraction previously. Origin and evolution of the cape mountains and karoo basin. Unpacking the issues around fracking in south africa. As yet very little systematic modern exploration for petroleum has been done the opportunity exists for a new generation of explorers to test the potential of these huge basins.
The southern main karoo basin of south africa is considered prospective for shale gas exploration. The supergroup consists of a sequence of units, mostly of nonmarine origin, deposited between the late carboniferous and early jurassic, a period of about 120 million years. Its name originated from the main karoo basin in south. Central kalahari karoo basin and its subdivision belts redrawn after smith, 1984.
Then, using the rockworks software, a 3d lithostratigraphic model of the kalahari karoo basin kkb was developed. Rare earth elements in select main karoo basin south. If found in commercially viable quantities, this gas could help secure south africas energy future, but only if we can preserve the unique character of the area as well. When the exploration began in 2018, there was a great deal of excitement and a number of karoo towns, especially in the central karoo basin. The editors at an exploration site on a dolerite sill in the victoria. Characterization of permian mangrullo formation uruguay. The main karoo basin of south africa is renowned for its exceptional palaeontological record and while its vertebrate fossils have been extensively researched, karoo floras have received considerably less attention. Click to edit master title style click to edit master subtitle style da silva, z. Furthermore, the effects of deformation, shale degassing, fluid migration and the natural fracturing characteristics of target shales i. The sediments in this 12km thick succession accumulated in an asymmetrical retroforeland basin, which resulted from the assembly of pangea catuneau et al. Karoo basin may 16 18 schematic crosssection through the karoo basin modified from johnson et al.
Petroleum potential of the karoo basins the karoo basins the karoo basins of southern africa record 100 million years of sedimentation in the heartland of the supercontinent gondwana, in a range of depositional environments. Karoo shale gas baseline research program gets on the way at nmmu. Morphological characteristics of ephemeral stream channel and overbank splay sandstone bodies in the permian lower beaufort group, karoo basin, south africa. Palaeoecology of the triassic molteno formation, karoo. Introduction the main karoo basin of south africa preserves a retroarc foreland basin fill cole 1992 deposited in front of the actively rising cape fold belt cfb in southwestern gondwana. Modie report on a field visit to exposures in the kalahari karoo basin of botswana the karoo supergroup of the kalahari basin. South africas karoo basin probably has a 30th of the shale gas deposits that some estimates had suggested, deflating. Overall, the karoo supergroup across the kalahari karoo basin reflects a transition from a glaciation period through to deltaic and swampy periods ultimately turning arid before the extrusion of. Depositional environments of the lower permian dwyka. Extensive outcrops in the tanqua depocentre, south. Generally, both pre and syn karoo fault systems are considered to have had a local influence on the distribution and thickness of the karoo sequence ecl 1998. This is an overview of the karoo basin in south africa, and its geologic setting. Current petroleum exploration activities in the karoo are focused on three unconventional play types. The first megatheropod tracks from the lower jurassic upper.
The potential impacts of fracking on biodiversity of the karoo basin, south africa chapter pdf available december 2016 with 2,054 reads how we measure reads. Pdf geophysically plumbing the main karoo basin, south. The karoo supergroup is the most widespread stratigraphic unit in africa south of the kalahari. The petroleum potential of south africas onshore karoo. Karoo supergroup the karoo supergroup, south africa, spans approximately 110 ma from the late carboniferous through the early jurassic. Carboniferouslower jurassic karoo succession in the central kalahari karoo sub. At first, crosssections over much larger, regional kalahari karoo basin kkb were developed to assess the vertical extension of each layer unit. The whitehill formation a high conductivity marker.
Hydrocarbonrich groundwater above shalegas formations. The base of the lystrosaurus assemblage zone, karoo basin. Darrah6 abstract horizontal drilling and hydraulic fracturing have enhanced unconventional hydrocarbon recovery but raised. The endpermian mass extinction is considered to represent generally the most severe ecological upheaval in the history of life, with an estimated species diversity loss in excess of 90%.
The karoo basins of southcentral africa sciencedirect. Tectonic evolution of the cape and karoo basins of south. The entire karoo basin and its sedimentary sequences are intersected by a number of deep boreholes. The karoo basin is a retroarc foreland basin developed associated foreland basin, subsequently fragmented as a in front of the cape fold belt cfb, in relationship to result of gondwana breakup, is preserved today in the late palaeozoicearly mesozoic subduction episode south america parana basin, southern africa karoo. The early ordovician to early carboniferous cape basin 160 ma is believed to have developed by extensional processes cloetingh et al. Shale gas developments in the karoo basin i 1 doug colehaajierah mosavel characterisation of surface dust and trapped dust samples around some asbestos mine dumps in mpumalanga province, south africa i 3 maphuti kwata the all new young geoscientists network i 4 refilwe shelembe first south africacanada bilateral collaboration. Dwyka to lower ecca groups in the karoo basin of southern africa catuneanu et al. Kirschvink,4 roger smith3 the karoo basin of south africa exposes a succession of upper permian to. A lithostratigraphic and magnetostratigraphic framework in. Abrupt and gradual extinction among late permian land. Petroleum potential of the karoo basins5 matchdeck. The basin is bounded by the cape fold belt along its southern margins and comprises up to 6 km of clastic sedimentary strata.
A palaeosurface with one megatheropod trackway and several theropod tracks and trackways from the lower jurassic upper elliot formation stormberg group, karoo supergroup in western lesotho is described. Contact metamorphic devolatilization of shales in the karoo basin, south africa, and the effects of multiple sill intrusions ingrid aarnesa. Aukarob hardveld is a semi desert natural region of south africa. Post 10 meandering in the main karoo basin ec south africa. Palynofacies patterns of the highveld coal deposits karoo basin, south africa. Geographically, the southern karoo basin hosts the primary unconventional reservoirplaytargets for.
The location of the still submersed cederberg and hex rivierbaviaanskloof mountains formed a stiff block against which the southwestern part of the karoo basin moved down for a while. Kalahari karoo basin outline showing subbasins after smith, 1984, major pre karoo structural lines after modie, 2007, and outline of the study area in orange. The main groundwater occurrences in the okavango basin are found in the basement rocks, the karoo system formations and the kalahari group formations and minor, but locally important occurrences, exist in the lightly metamorphosed late precambrian palaeozoic sediments. The karoo basin system in the nwtrendingubende belt in tanzania and east congo is a manifestation of the early stage of gondwana breakupin eastcentralafrica. The term karoo was extrapolated from the main karoo basin of south africa, to describe the sedimentary fill of all other basins of. During that time of increasing water depth mainly clays were deposited, followed by the tanqua karoo deepwater sand deposits.
Upb zircon tuff geochronology from the karoo basin, south. The majority of the theropod tracks are referable to either eubrontes or kayentapus based on their morphological characteristics. Hydrogeology of the main karoo basin water research commission. If the inline pdf is not rendering correctly, you can download the pdf file here. Ecca group shales within the karoo basin are poorly understood and integrated. For this reason, the karoo basins sensu stricto, which show clear similarities with the main karoo basin of south africa, are generally restricted to southcentral africa fig. The karoo basin reaches 600,000 sq km in central and southern south africa and contains thick, organic rich shales such as the permian whitehill formation. A stratigraphic framework at old lootsberg pass, karoo basin geological society of america bulletin, v. These reflect the progressive infilling of the karoo basins, the changing tectonic framework as well as the migration of gondwana from polar to tropical latitudes. The karoo basin is bounded on its southern margin by the cape fold belt. Upb zircon tuff geochronology from the karoo basin, south africa. Sedimentary deposits of the karoo sequence in northwestern damaraland are exposed in the goboboseb mountains south of the ugab river, as well as in an area approximately 100 by 50 km wide on both the northern and southern sides of the huab river fig.
No exact definition of what constitutes the karoo is available, so its extent is also not precisely defined. The ellisras basin is about 320 kilometres 200 mi north of the main karoo basin. The karoo supergroup is the largest stratigraphic unit in southern africa, covering almost two thirds of the present land surface, including central cape province, almost all of orange free state, western natal, much of southeast transvaal, zambia, zimbabwe and malawi. The laingsburg depocentre of the sw karoo basin, south africa preserves a wellexposed 1200 m thick succession of upper permian strata that record the early filling of a basin during an icehouse. The karoo supergroup is the most widespread stratigraphic unit in africa south of the kalahari desert.
The karoo basin covers around 610,000 square kilometres 237,000 square miles, and its size and geology lends itself to potentially enormous volumes of unconventional shale gas. This book describes the latest research on the geological, geochemical, geochronological, biological, and geomorphic evolution of the unique and relatively pristine landscape of the cape mountains and the karoo basin, a region in south africa that is currently being targeted for shale gas exploration and development. Post 10 meandering in the main karoo basin, eastern cape, south africa. Jul 25, 2017 this is an overview of the karoo basin in south africa, and its geologic setting. Geothermal energy from the main karoo basin south africa. Ransome editors inversion tectonics of the cape fold belt. The endpermian is associated with major changes in both marine and terrestrial biodiversity. Multistage evolution of dolerites in the karoo large igneous. Rare earth elements in select main karoo basin south africa coal and coal ash samples. Late permian karoo basin tectonics in south africa are reflected as two finingupward megacycles in the balfour and upper teekloof formations. In the case of the karoo basin, the hvc represent pipelike piercement structures formed in a subaerial basin setting svensen et al. The supergroup consists of a sequence of units, mostly of nonmarine origin, deposited between the late carboniferous and early jurassic, a period of about 120 million years in southern africa, rocks of the karoo supergroup cover almost two thirds of the present land surface, including all of. More than 500 hydrothermal vent complexes are mapped in the karoo basin, and the complexes range from.
The karoo basin is located within longitude 17 e and 30 e and latitude 25 s and 33 s fig. Clues to reconstruction of palaeoenvironment and palaeoclimate. Abrupt and gradual extinction among late permian land vertebrates in the karoo basin, south africa peter d. The karoo basin lies north of the cape fold belt, and the karoo supergroup comprises the erosional detritus shed from the uplifting cape fold belt catuneanu et al. Structure and evolution of hydrothermal vent complexes in. Prospectivity is greatest in the south west of the basin, where the shales have a high organic content, are thermally mature and sufficiently thick. The cause of this mass extinction is still a matter of debate. The karoo basin occupies an area of approximately 66 % of the southern part of the african continent comprising mostly sedimentary rocks of paleozoic age hamilton and finlay 1928. Magnetostratigraphic constraints on the age of the lower.
Poor yields of palynomorphs from the beaufort and stormberg groups have complicated the. The karoo basins of southcentral africa evolved during the firstorder cycle of supercontinent assembly and breakup of pangea, under the influence of two distinct tectonic regimes sourced from. Structure and evolution of hydrothermal vent complexes in the karoo basin. The erosional remants of the main karoo basin cover approximately. Pdf structure and evolution of hydrothermal vent complexes in the. The karoo supergroup itself overlies the earlytomiddle paleozoic cape supergroup, principally composed of quartzose sandstones and subordinate. Pdf the potential impacts of fracking on biodiversity of. The karoo sediments in the sbf basin clearly represent the broad spectrum of the same set of palaeo environments that are recognized in the main karoo basin rocks. Is the deepseafan laingsburg formation permian, karoo basin, south africa in fact.
For more information, download the petroleum potential of the karoo basins pdf here. Palynofacies patterns of the highveld coal deposits karoo. New late permian tectonic model for south africas karoo basin. Multistage evolution of dolerites in the karoo large. Depositional environments varied geographically in the karoo basin and ranged from marine to lacustrine for the dwyka to lower ecca groups of southern africa. The aim of that paper was to test geochemical similarities or differences between sills and dykes in the golden valley sill complex to throw light on their emplacement mechanism. A provisional basin analysis of the karoo supergroup. Historical reflection seismic, petroleum exploration wells and regional magnetic data are used to better understand the. Karoo basin shale gas unconventional concept play report. Petrography and geochemistry of sandstone samples of. Deflating the shale gas potential of south africas. The great karoo basin covers an area of over 700,000 km 2 and constitutes a retroarc foreland basin.
Along the basin s southern margin the karoo succession attains a maximum composite thickness of 12 km. South africa karoo shale gas deposits seen less than. Van zijl 1977 published a practical manual on the resistivity method. Breeding young as a survival strategy during earths greatest. Contact metamorphic devolatilization of shales in the karoo. The karoo basin shell has applied for rights to explore for natural gas in the karoo. Recent interest in the main karoo basin of south africa has been sparked by the possibility of extensive shale gas resources. Drake, editors, studies in continental margin geology. Predrill groundwater geochemistry in the karoo basin.
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