@article {2636,
	title = {Using Stable Carbon Isotopes to Quantify Radiocarbon Reservoir Age Offsets in the Coastal Black SeaAbstract},
	journal = {Radiocarbon},
	volume = {61},
	year = {2019},
	month = {Jan-02-2019},
	pages = {309 - 318},
	abstract = {Constraining radiocarbon (C-14) reservoir age offsets is critical to deriving accurate calendar-age chronologies from C-14 dating of materials which did not draw carbon directly from the atmosphere. The application of C-14 dating to such materials is severely limited in hydrologically sensitive environments like the Black Sea because of the difficulty to quantify reservoir age offsets, which can vary quickly and significantly through time, due to the dynamics of the biogeochemical cycling of carbon. Here we reconstruct C-14 reservoir age offsets (Rshell-atm) of Holocene bivalve shells from the coastal Black Sea relatively to their contemporaneous atmosphere. We show that the C-14 reservoir age offset and the stable carbon isotope composition of bivalve shells are linearly correlated in this region. From a biogeochemical standpoint, this suggests that inorganic stable carbon isotope and C-14 compositions of Black Sea coastal waters are controlled by the balance between autochthonous primary productivity and heterotrophic respiration of allochthonous pre-aged terrestrial organic matter supplied by rivers. This provided an important implication for Black Sea geochronology as the reservoir age offset of C-14-dated bivalve shell can be inferred from its stable carbon isotope composition. Our results provide a fundamental and inexpensive geochemical tool which will considerably improve the accuracy of Holocene calendar age chronologies in the Black Sea.},
	keywords = {Black Sea, Carbon cycle, freshwater reservoir effect, Geochronology, Reservoir age},
	issn = {0033-8222},
	doi = {10.1017/RDC.2018.61},
	url = {https://www.cambridge.org/core/product/identifier/S0033822218000619/type/journal_articlehttps://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0033822218000619},
	author = {Soulet, Guillaume and Giosan, Liviu and Flaux, Cl{\'e}ment and Galy, Valier}
}
@article {2531,
	title = {Compilation of geophysical, geochronological, and geochemical evidence indicates a rapid Mediterranean-derived submergence of the Black Sea{\textquoteright}s shelf and subsequent substantial salinification in the early Holocene},
	journal = {Marine Geology},
	volume = {383},
	year = {2017},
	month = {Jan-01-2017},
	pages = {14 - 34},
	abstract = {Our knowledge of rate and processes in which semi-enclosed environments alternate from lacustrine to marine is commonly limited because of the paucity of specific proxies for sea level and salinity. Here we investigate the timing, rate, and key mechanisms involved in the transformation of the previously isolated Black Sea-Lake to the modern partly-enclosed marine sea using a suite of geophysical, geochemical, and geochronological methods.

Cores were collected in transects across shelves of Ukraine, Romania, Bulgaria, and Turkey. Biogenic carbonate from these cores was analyzed for radiocarbon and strontium, oxygen, and carbon isotopes. Strontium results indicate that the submergence of the Black Sea shelf at 9300 calendar years BP was caused by the ingress of Mediterranean water and was abrupt, taking < 40 years. The seismic reflection profiles show a uniform drape of subsequent sediment over aeolian dunes indicating a drowning with no time for erosion accompanying the submergence. Moisture measurements beneath the uniform drape indicate that the shelf was dry before submergence and the shoreline of the Preboreal lake may have regressed to beyond 120 mbsl. Mollusks colonized the newly submerged substrate of the inner shelf at the same time as they colonized the outer shelf. The succession of mollusk species with shells whose strontium isotope composition has a marine component indicates a rising salinity. The transformation of the lake to a sea is affirmed by increases in the shells{\textquoteright} strontium and oxygen isotopic ratios towards the external ocean value.

Radiocarbon years are calibrated to calendar years by tuning the oxygen and carbon isotope composition of the mollusk record to that of the U/Th dated Sofular Cave stalagmites. The match shows a reduction of the lake{\textquoteright}s prior high reservoir age accompanying the inflow of the Mediterranean water. In 900 years the salinity reached a threshold that excluded all previous Black Sea lacustrine fauna. These results imply that any substantial postglacial submergence of the Black Sea shelves did not occur prior to entry of Mediterranean water.},
	keywords = {Black Sea, Black Sea transgression, Isotope geochemistry, Lake transgression, Marine-lake connections, paleoceanography, paleosalinity, Reflection profiles},
	issn = {00253227},
	doi = {10.1016/j.margeo.2016.11.001},
	url = {https://doi.org/10.1016/j.margeo.2016.11.001},
	author = {Yanchilina, Anastasia G. and Ryan, William B.F. and McManus, Jerry F. and Dimitrov, Petko and Dimitrov, Dimitar and Slavova, Krasimira and Filipova-Marinova, Mariana}
}
@article {911,
	title = {Identification of a novel alkenone in Black Sea sediments},
	journal = {Organic Geochemistry},
	volume = {32},
	year = {2000},
	note = {id: 1719},
	pages = {633-645},
	abstract = {We report the identification of a novel long-chain ketone in Holocene Black Sea sediments. Based on chemical properties, and chromatographic and mass spectrometric characteristics, this compound has been identified as a di-unsaturated C36 ethyl ketone. Further analyses indicated the position and configuration of the double bonds, and the novel alkenone was determined to be hexatriaconta-(16E,21E)-dien-3-one. While this compound is present in only trace quantities in Unit I sediments, it is the most abundant alkenone in portions of Unit II. Its presence thus apparently pre-dates the invasion of Emiliania huxleyi in the Black Sea. The down-core profiles and isotopic compositions suggest that the precursor for the C36:2 alkenone may be distinct from that of the C37-39 alkenones, however the biological origin of this novel compound is presently unknown.},
	keywords = {Alkenone, Black Sea, Haptophytes, Holocene, Sediment, Structure characterization},
	doi = {10.1016/S0146-6380(01)00019-5},
	author = {Xu, L. and Reddy, C. M. and Farrington, J. W. and Frysinger, G. S. and Gaines, R. B. and Johnson, C. G. and Nelson, R. K. and Eglinton, T. I.}
}
