Radiolarian Age Constraints of Mid-Cretaceous Black Shales in Northern Tunisia
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The Beyşehir–Hoyran–Hadim Nappes: genesis and emplacement of Mesozoic marginal and oceanic units of the northern Neotethys in southern Turkey
The Beyşehir–Hoyran–Hadim Nappes crop out over 700 km from NW to SE. Above a regionally autochthonous Tauride carbonate platform the Beyşehir–Hoyran Nappes begin with a thrust sheet (c. 400 m) of mainly redeposited carbonates, quartzose sandstones and mudstones of Mid–Late Triassic age, interpreted as a proximal slope–base-of-slope succession. Above is a thrust sheet (c. 1 km) of Middle–Upper T...
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This paper presents a new interpretation of the geometry of Triassic alignment of J. Sidi Mahdi –J. Zitoun in Medjerda Valley Plain (Northern Tunisia) based on detailed analysis of gravity and seismic reflection data. The main results of gravity analysis do not show a distinguish gravity anomaly over Triassic evaporites bodies. The positive gravity anomaly seems to be related to the entire stru...
متن کاملIntroduction and Overview
The term "black shale" is a common expression widely used to describe any dark~olored, fine-grained sedimentary rock relatively rich in organic matter. As defined by Weissert (1981), the range of organic carbon in black shales is between 1 and 30%, but values outside this range exist. The term usually connotes at least partial lithification, yet this may not be true in young, shallow sediments....
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The investigated section cropping out in Kuh-e-Banesh, Zagros basin (southern Iran) is represented by limestone, Cherty beds and marllevels bearing abundant Planktonic foraminifers, radiolarian microfaunas, and ammonite imprints. For the first time, well to moderatelypreserved forms of Planktonic foraminifera have been extracted from black shale and marls levels. Extracted biota was studied wit...
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Black shale is dark-colored, organic-rich sediment, and there have been many episodes of black shale deposition over the history of the Earth. Black shales are source rocks for petroleum and natural gas, and thus are both geologically and economically important. Here, we review our recent progress in understanding of the surface ocean ecosystem during periods of carbonaceous sediment deposition...
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