Black Sea Sedimentary Framework

Abstract

This paper summarizes results from important previous Black Sea sedimentary studies in order to provide background information useful for the interpretation of data from Leg 42B drilling. The information presented is basically derived from Atlantis II Cruise 49 (Degens and Ross, 1974) by the Woods Hole Oceanographic Institution and from cruises of the research vessels Akademik S. Vavilov, Vityaz, and Academik Shirshov of the Institute of Oceanology of Academy of Sciences of the Soviet Union (summarized by Shimkus and Trimonis, 1974). A listing of important literature concerning the biology, geology, chemistry, and geophysics of the Black Sea has been compiled by Laking, 1974. BLACK SEA DRAINAGE AREA The drainage area of the Black Sea is about 1,864,000 km 2 (Figure 1) of which approximately 85% belongs to the Russian Platform, and about 15% to high mountain areas. Generally low relief is found on the Russian Platform and Walachian Lowlands to the north and west. The rivers (Danube, Dnester, Bug, Dneper, Don) draining these areas have low velocity and limans at their mouths (see Shimkus and Trimonis, 1974, for a more detailed discussion). In the southwest, south, and east, the Black Sea is surrounded by mountainous regions (Balkan, Pontic, and Caucasus mountains). In contrast with the wide, large rivers of the north and northwest, this area has numerous small, but extremely erosive, rivers. As shown by Table 1, all rivers deposit a total of about 150 million tons of solid material per year into the Black Sea. This number should be considered as a minimum value, because the quantity of sediments transported by the Turkish rivers is probably larger than 17 million tons per year. The importance of organic productivity and river detritus to the sediment budget of the Black Sea can be seen from Figure 2. Based on the data of Table 1 and Figure 2, the Danube is presently by far the most important river draining into the Black Sea. REGIONAL GEOLOGY The Black Sea is located between the Paleozoic Russian Platform and the Mediterranean geosyncline which was folded during the Alpine orogeny. The Russian Platform represents a peneplain surface of Paleozoic, Mesozoic, and Tertiary sedimentary rocks (Figure 3). White chalks, marls, and argillaceous and sandy sedimentary units of Mesozoic and Tertiary age dominate the middle and southern part of the

Sediment dynamics in the Black Sea: numerical modelling and remote sensing observations

“…A value of M e,b = 3.7 × 10 −7 kg m −2 s −1 (Stanev et al 2007) combined with the topography dependency (Eq. 14) ensured reasonable simulations consistent with the distribution of bottom sediment given by Ross et al (1978). We admit, however, that the spatial variability of M e needs to be further improved by developing basin wide maps of bottom properties based on measurements.…”

“…It mimicked aspects of long-term depositional pattern observed in Holocene stratigraphy (see Fig. 7 from Ross et al 1978). Danube sediments travelled southward during a series of episodic transport events.…”

“…The sediment pattern in the near-shore zone of the Black Sea is governed by the surface and alongshore bottom currents and wave action (Ross et al 1978;Nikolov et al 2006). In the western Black Sea, suspended particulate mater (SPM) from the Danube, Dnieper and other big rivers is deposited and trapped on the broad western shelf.…”

Budget of Post-Rifting Sediments in the Gulf of California and Calculation of the Denudation Rate in Neighboring Land Areas

“…If the sediment load of the entering rivers (the Danube from the Alps being the most prominent) is spread equally over the total basin area, a sedimentation rate of 14 cm/ky. results for dry terrigenous material with a 2.5 g/cm 3 specific gravity (calculated from data provided by Ross and Trimonis, 1978).…”

A Greigite-Based Magnetostratigraphic Time Frame for the Late Miocene to Recent DSDP Leg 42B Cores from the Black Sea

“…In 1975, during DSDP Leg 42B in the Black Sea, three holes (379A, 380/380A, and 381) were drilled with a total of 2318 m cored and a recovery of 55% (Figure 1; Ross et al, 1978). While by modern standards this may not be particularly noteworthy, these sites still represent the longest record of sedimentation in the deep, basinal part of the Black Sea.…”