Marine organic facies

Paleozoic limestone (Webb et al. 2004). These kimberlites all have similar groundmass mineralogies consisting mainly of carbonate, spinel, and serpentine with lesser monticellite, mica, apatite, and perovskite (Kong et al. 1999) and they are all of volcaniclastic facies near ground surface. Varying thicknesses of clay and fine marine sediments of the Tyrell Sea ( 4000 - 12000 years BP) and 1 to 4 m of peat overlie kimberlites (Fraser et al. 2005). Bioherms composed of coral and skeletal remains of other marine organisms sometimes outcrop. 

Phytoplankton should be regarded as the main supplier of organic carbon in ancient marine sediments. However, it should be kept in mind that the distribution of observed in the facies profile does not coincide spatially with the distribution of phytoplankton and production of oxygen, as most dead plankton decomposes in the surface layer, as a result of which the accumulation of organic matter would be considerably greater in the nearshore zone than in the deep sea. 

OC and K series), non-marine (D, Ca and C series) and transitional (B series) deposits. Within each series organic matter is often found in quite different facies, for instance acid treatment (Table III) indicates that within the Lothians Upper Oil Shale group samples Cal and Ca6 are carbonate rich (>40%) whereas Cal5 is carbonate poor (2.5%) 5 these differences are obvious within other series as noted in Table III. Microscopical analysis of polished blocks in white and blue light allowed the data in Table II to be compiled. 

Framvaren has a well documented history of environmental change from fjord to lake and then back to a fjord. Sediment cores from both oxic and anoxic past environments contain organic carbon contents of 6-18% and reveal complex distributions of lipid compounds, the dominant classes being n-alkanes, n-alcohols, sterols and long-chain alkenones (Ficken Farrimond, 1995). The alkenones, which are predominantly produced by marine prymnesiophyte algae, are most abundant in the fjord facies of both cores, but are also detectable in the lacustrine sediments, albeit in much lower concentrations. The dramatic increase in abundance of these compounds is interpreted to record the change in environment from lake to fjord. 

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