کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
5785744 1640179 2017 16 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Subsurface Permian reef complexes of southern Tunisia: Shelf carbonate setting and paleogeographic implications
ترجمه فارسی عنوان
مجتمع های صخره ای پرمین جنوبی جنوب تونس: تنظیم کربنات قفسه و پیامدهای پیلوگوئوگرافی
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات زمین شناسی
چکیده انگلیسی


- Reef complexes correspond to fossiliferous limestone and dolomite.
- Lithostratigraphic correlations pinpoint the lateral and vertical facies evolution of Middle to Late Permian sequences.
- The identified reef barrier is trending WNW-ESE and may be extended to Bir Soltane area westward.
- Inner shelf carbonate sedimentary succession corresponds to an interbedding of dolomite, shallow marine limestone, shale and anhydrite and patch reef constructions.
- Upper Permian facies, southward, thins out and bear witness of landward influences.

2-D seismic reflection sections, borehole data as well as published and unpublished data have been investigated to reconstruct the paleogeography of southern Tunisia during Middle to Late Permian times. Paleogeographical reconstruction based on the integration of petroleum well data and 2-D seismic facies interpretation shows three main depositional areas with very contrasting sedimentary pile. These are 1) a subsiding basin; 2) an outer shelf carbonate, and 3) an inner shelf carbonate. Based on typical electric responses of reef buildups to seismic wave, we shall urge that during Middle Permian times, the outer carbonate shelf was subject of reef barrier development. Lithology evidences from core samples show that reef framework correspond mainly to fossiliferous limestone and dolomite. The WNW-ESE recognized reef barrier led between latitudes 33° 10′ 00″N and 33° 20′ 00″N. The Tebaga of Medenine outcrop constitutes the northern-edge of this barrier. Westward it may be extended to Bir Soltane area whereas its extension eastward is still to be determined. Biogenic buildups took place preferentially over faulted Carboniferous and lower Paleozoic paleohighs resulting likely from the Hercynian orogeny. The subsiding basin is located north of Tebaga of Medenine outcrop where Upper Permian sedimentary sequence is made entirely of 4000 m deep marine green silty shale facies. These are ascribed to unorganized and chaotic reflectors. Inner carbonate shelf facies succession corresponds to a typical interbedding of shallow marine carbonate deposits, shale, dolomite, and anhydrite inducing parallel-layered of strong amplitude and good continuity reflectors. Also within the inner carbonate shelf patch reef or reef pinnacles have been identified based on their seismic signature particularly their low vertical development as compared to reef complexes. Southward, towards Sidi Toui area, the Upper Permian depositional sequence thins out and bears witness of land influences as entailed by the increase of silicoclastic sedimentary supply and the lack of marine fossil.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of African Earth Sciences - Volume 129, May 2017, Pages 944-959
نویسندگان
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