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Late cretaceous paleogeography of northern Israel and its significance for the Levant geology
Authors:A Flexer
Institution:

Department of Geography, Tel-Aviv University, Tel-Aviv, Israel

Abstract:Senonian-Maastrichtian sediments in northern Israel are characterized by a thick sequence of homogeneous chalk containing profuse planktonic foraminiferids and coccolithophorids. The occurrence (or absence) of chert, bitumen, quartz grains, phosphate content, the variations of plankton-benthos ratio, the generic and family composition of Foraminifera and thickness variations indicate that the sediments were deposited on an outer shelf area in a very non-turbulent pelagic sea. This sea, part of the Tethys ocean which covered all the Levant during the Late Cretaceous, became epicontinental in the vicinity of the Arabo-Nubian Massif. Thickness of sediments is a function of submarine depressions, wedge-out occurring towards uplifted areas which by and large are also present-day structures, except for the western part of the area. Here, non-sedimentation or sediments of reduced thickness can be explained by deposition on a steep part of the continental shelf beyond the shelf break or by erosion due to submarine currents on the outer shelf.

The depth of the sea changed with time. Santonian sediments were deposited in water of relatively great depth (several hundred metres) which decreased during the Early Campanian and attained a minimum in very Late Campanian time. During Early to Late Maastrichtian time subsidence recommenced.

Three marine facies belts are differentiated in the Late Cretaceous chalks of the Levant countries. The data of these rocks in northern Israel (part of the extreme western belt having poorly-defined continental affinities) were utilized in the palaeogeographic analysis of the Levant region.

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