气候变化领域集成服务门户(CCPortal): Evolution of an Archaean intracratonic basin: A review of the Transvaal Supergroup lithostratigraphy in Botswana

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DOI	10.1016/j.earscirev.2019.02.007
	Evolution of an Archaean intracratonic basin: A review of the Transvaal Supergroup lithostratigraphy in Botswana
	Franchi F.; Mapeo R.B.M.
发表日期	2019
ISSN	0012-9015
起始页码	273
结束页码	290
卷号	191
英文摘要	Several lithostratigraphic and radiometric-dating studies over the last half century have generated a robust stratigraphic data set about the Transvaal Supergroup sedimentary deposits throughout southern Africa. The Transvaal Supergroup in southern Africa represents one of the best examples of a Precambrian intracratonic sequence, including one of the best preserved and extensive Archaean/Palaeoproterozoic carbonate platforms. Sediments of the Transvaal Supergroup are hosted on the Kaapvaal Craton in three areas of South Africa and Botswana. Critically, the smallest of the three Transvaal depocentres, the Kanye Basin (including the Molepolole-Mochudi sub-basin), is the least known, and the stratigraphic model is still incomplete. The Kanye Basin in southern Botswana exposes a mixed volcanic-sedimentary succession spanning from the Meso-Neoarchaean to the Palaeoproterozoic, including the complete sequence of the Lower Transvaal Supergroup (LTS) and the lower part of the Upper Transvaal Supergroup (UTS). Although no consensus has been reached so far, the deposition of the Transvaal-age sediments in Botswana likely followed the same thermal and tectonic processes recorded in South Africa, albeit diachronously. The initial stage of rifting was followed by sediments that formed in an epicontinental sea setting that recorded the deepening of the basin. The younger sequence records the reactivation of the extensional tectonics alternating with post-rift thermal subsidence. The nomenclature of the lithostratigraphic units in Botswana is often inconsistent, and the correlations with the main Transvaal basins in South Africa are imprecise. Because of the importance of the Transvaal Supergroup for economic (e.g., skarn deposits and placers) and hydrologic (e.g., the Ramotswa trans-boundary aquifer) reasons, the lack of a consistent nomenclature can introduce ambiguity in the scientific literature and lead to misinterpretations. A thorough lithostratigraphic revision of the Transvaal Supergroup in Botswana will also solve the puzzle of the Transvaal-age deposits in southern Africa, allowing reliable interpretations across the three basins. Here, a comprehensive lithostratigraphic and chronostratigraphic description of the Transvaal Supergroup is provided based on literature data and new observations. New lithostratigraphic charts are produced for the Kanye Basin, revealing the stratigraphic relationships within the different Transvaal basins and the effect of cyclicity in the evolution of this Precambrian basin. © 2019 Elsevier B.V.
英文关键词	Archaean; Botswana; Great Oxidation Event; Kaapvaal Craton; Kanye Basin; Precambrian Basin; Proterozoic
语种	英语
scopus关键词	Archean; basin analysis; basin evolution; carbonate platform; extensional tectonics; inland sea; intracratonic basin; lithostratigraphy; Proterozoic; radiometric method; rifting; Botswana; Kaapvaal Craton; South Africa; Transvaal
来源期刊	EARTH-SCIENCE REVIEWS
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/209926
作者单位	Department of Earth and Environmental Science, Botswana International University of Science and Technology (BIUST), Private Bag 16, Palapye, Botswana; Department of Geology, University of Botswana, Private Bag UB00704, Gaborone, Botswana
推荐引用方式 GB/T 7714	Franchi F.,Mapeo R.B.M.. Evolution of an Archaean intracratonic basin: A review of the Transvaal Supergroup lithostratigraphy in Botswana[J],2019,191.
APA	Franchi F.,&Mapeo R.B.M..(2019).Evolution of an Archaean intracratonic basin: A review of the Transvaal Supergroup lithostratigraphy in Botswana.EARTH-SCIENCE REVIEWS,191.
MLA	Franchi F.,et al."Evolution of an Archaean intracratonic basin: A review of the Transvaal Supergroup lithostratigraphy in Botswana".EARTH-SCIENCE REVIEWS 191(2019).