Palaeoenvironmental studies of organic-rich shales
An integration of stratigraphic and geochemical data sheds light on the depositional palaeoenvironment and hydrocarbon-yield potential of organic carbon-rich shales.
A combination of outcrop and drilling-core studies allows recognition of the origin (palaeonvironment), depositional conditions and physico-chemical properties of ´black shales´ -- the crucial source-rocks for petroleum. The studies integrate stratigraphic geological knowledge with geochemical data, including: (a) stable-isotope analysis of organic matter (d13C, d15N), biogenic carbonate (d13C, d18O) and framboidal pyrite (d34S); (b) trace-element analysis (Mo, Cu, Zn, Ni); (c) Rock Eval® analysis (TOC, HI); and (d) analysis of various biomarkers. The research results improve our knowledge on the origin of petroleum and on the hydrocarbon generation potential of particular 'black shale' units in subsurface rock successions.