Characteristics and conditions of accumulation of the Upper Jurassic sediments in the South-Eastern Caucasus
Mehdiyeva Z.N.
Institute of Geology and Geophysics, Ministry of Science and Education Republic of Azerbaijan, Baku, AZ1143, H.Javid av., 119 E-mail: zabita.mehdiyeva@gmail.com
The article discusses characteristic structural features of the Southeastern Caucasus region and some geochemical aspects of the lithogenesis of the Upper Jurassic deposits. It studies and characterizes sediments of the various zones (Sudur, Shahdagh-Khizi and Guton-Gonagkend) based on the sections exposed in the river valleys of Gilgilchay, Babachay and Jimichay. Although many studies had covered tectonics, structural geology, stratigraphy and paleontology of the Jurassic succession in the Southeastern Caucasus, there are still questions that require more detail investigations of the stratigraphy, genesis and typification of various rhythmically bedded successions as well as sources of the clastic material. Experienced difficulties in these studies are caused, firstly, by the complex tectonic structure of the region and, secondly, by the lack of necessary paleontological data.
Upper
Jurassic succession in the studied areas is composed of conglomerates,
sandstones, siltstones, mudstones, and carbonate rocks, all combined in the
local suites. In general, the color and lithological patterns of these
terrigenous-carbonate and carbonate sequences differ in the various localities.
Based on
chemical and mineralogical analysis of the rocks, and the collection and
interpretation of archive and published materials, the article provides a
ground for the lithochemical characterization of the studied sections in the
Shahdagh-Khizi zone, stratigraphically identified as the Upper
Oxfordian-Kimmeridgian (Gyzylgazma Formation).
Keywords: Southeastern Caucasus, facies variability, Gyzylgazma Formation, Shahdagh-Khizi zone, geochemical indicators, felsic provenance