Tectonics of Pleistocene Deposits in the Northeast of Taman Peninsula, South Azov Sea Region

Abstract

Studies in paleomagnetism, structural geology, and paleontology (mammals, mollusks, palynology) in the coastal sections of the Taman Peninsula north-western part (2017–18) resulted in definition of three sedimentary sequences. The sandy and clayey lower sequence (I) formed at 2.1–1.7 Ma. It contains a normally magnetised zone within deposits of reversed polarity correlated to the Olduvai Subchron and the Matuyama Chron. The middle sequence (II) is composed of the basal pebbles overlain by sands. The reversely magnetised deposits hosting the Sinyaya Balka site, the type locality of the Tamanian faunal complex, is correlated to the basal bed of the middle sequence II. The overlying sands are normally magnetised (Jaramillo Subchron) in the lower part and show reverse polarity (late Matuyama Chron) in the upper part. The sequence II is dated in the range of 1.3–0.78 Ma. The silty upper sequence (III) represents Middle-Late Pleistocene. The dissimilar displacement degree of the sequences reflect developmental stages of the Quaternary deformation. The sequence I is characterised by dip angles up to 70° is fragmented by faults into blocks. The sequence II filled the relief of the eroded surface of the sequence Member I and also displaced by faults. The faulting separated the bone-bearing body of the Taman faunal complex as a rock land-slide. The attitude of the member III outline an anticline with a gentle south-western and a steeper north-eastern limbs eroded by land-slides and marine abrasion. During its entire life the anticline was affected by mud volcanism. The anticline continues its development at the present stage.