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Shell concentrations from the Miocene Ar Rajmah Group at Soluq-Al Abyar road cut, southern Al Jabal Al Akhdar, NE Libya

  • ArabGU2016
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Abstract

The Miocene Ar Rajmah Group, exposed along the Soluq-Al Abyar road cut in southern Al Jabal Al Akhdar, NE Libya, is very rich in both micro- and macrofossils, especially molluscs and echinoids. Seven shell concentrations were recognized of which four from the Benghazi Formation; pectinids–small oyster concentration (BSC1), Echinolampas sp.–Clypeaster cf. martini concentration (BSC2), molluscan shell concentration (BSC3), and Echinolampas cf. amplus–Clypeaster acclivis concentration (BSC4). Three shell concentrations occur in the Wadi Al Qattarah Formation; large oyster concentration (QSC1), Crassostrea gryphoides–Chlamys zitteli concentration (QSC2), and Cubitostrea digitalina concentration (QSC3). The main factors controlling the formation of the shell concentrations were storm-induced waves and currents, reduced sediment input, settling behavior of benthic macro-invertebrates, and productivity.

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Acknowledgements

We are greatly appreciated to Professors F.T. Fürsich (Eralngen University, Germany) and M. A.M. Abdelhamid (Ain Shams University, Egypt) for reading an earlier typescript and providing constructive comments. The assistance during the field work by Mr. M. El Namous and Mr. U. El-Sherief (Earth Sciences Department, Benghazi University) is greatly appreciated. We also thank Mr. Adel Al-Marime and Mr. Walead Al-Kafiefi (the Gulf Oil Company) for their support in preparing some thin-sections and printing their photomicrographs.

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Authors and Affiliations

  1. Geology Department, Faculty of Science, Benha University, Benha, Egypt

    Gamal M. El Qot

  2. Earth Sciences Department, Faculty of Science, Benghazi University, Benghazi, Libya

    Esam O. Abdulsamad & Abdelsalam El Fakhry

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  1. Gamal M. El Qot
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  2. Esam O. Abdulsamad
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  3. Abdelsalam El Fakhry
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Correspondence to Gamal M. El Qot.

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This article is part of the Topical Collection on Current Advances in Geology of North Africa

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El Qot, G.M., Abdulsamad, E.O. & El Fakhry, A. Shell concentrations from the Miocene Ar Rajmah Group at Soluq-Al Abyar road cut, southern Al Jabal Al Akhdar, NE Libya. Arab J Geosci 10, 47 (2017). https://doi.org/10.1007/s12517-016-2789-8

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