TY - JOUR N2 - The organic carbon (OC)-rich, black shale succession of the Middle Triassic Bravaisberget Formation in Spitsbergen contains scattered dolomite-ankerite cement in coarser-grained beds and intervals. This cement shows growth-related compositional trend from non-ferroan dolomite (0–5 mol % FeCO3) through ferroan dolomite (5–10 mol % FeCO3) to ankerite (10–20 mol % FeCO3, up to 1.7 mol % MnCO3) that is manifested by zoned nature of composite carbonate crystals. The d13C (-7.3‰ to -1.8‰ VPDB) and d18O (-9.4‰ to -6.0‰ VPDB) values are typical for burial cements originated from mixed inorganic and organic carbonate sources. The dolomite-ankerite cement formed over a range of diagenetic and burial environments, from early post-sulphidic to early catagenic. It reflects evolution of intraformational, compaction-derived marine fluids that was affected by dissolution of biogenic carbonate, clay mineral and iron oxide transformations, and thermal decomposition of organic carbon (decarboxylation of organic acids, kerogen breakdown). These processes operated during Late Triassic and post-Triassic burial history over a temperature range from approx. 40°C to more than 100°C, and contributed to the final stage of cementation of the primary pore space of siltstone and sandstone beds and intervals in the OC-rich succession. L1 - http://www.czasopisma.pan.pl/Content/110549/PDF-MASTER/PPR30-231.pdf L2 - http://www.czasopisma.pan.pl/Content/110549 PY - 2009 IS - No 3 EP - 248 KW - Arctic KW - Svalbard KW - Middle Triassic KW - cementation KW - petrography KW - geochemistry KW - carbon and oxygen isotopes A1 - Krajewski, Krzysztof P. A1 - Woźny, Ewa PB - Polish Academy of Sciences PB - Committee on Polar Research VL - vol. 30 DA - 2009 T1 - Origin of dolomite-ankerite cement in the Bravaisberget Formation (Middle Triassic) in Spitsbergen, Svalbard SP - 231 UR - http://www.czasopisma.pan.pl/dlibra/publication/edition/110549 T2 - Polish Polar Research ER -