Facies profile

Free carbon content in various rocks of the facies profile of the BIF of the KMA (after Plaksenko)... 

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. 

Contents of REE in massive sulfides from the BMC are strongly controlled by the abundance of and REE concentrations in phosphate minerals, specifically apatite, xenotime and monazite. Strong positive Eu anomalies in apatite, account for the anomalous Eu signatures of exhalative sulfides whereas REE in monazite masses are largely reflective of detrital sources and may mask hydrothermal signatures. Limited release of mobile trace elements (LREE and Eu) during green-schist facies metamorphism has partly modified REE profiles for VMS deposits of the BMC. 

The concentrations of the total alkylthiophenes (except thiophene hopanoids) in the bitumens show a depth profile somewhat similar to that of the total sulfur content (cf. Figures 6a and Id). The high concentrations of alkylthiophenes in Facies B compared to A and C are consistent with the proposed incorporation of inorganic sulfur species into specific funtionalised lipids in anoxic marine environments (6-12). 

The depth profiles of the two isoprenoid thiophenes (Figure 16a-b) are similar. Both profiles show maxima (at 56m and 83m) in Facies A. Recently, the structures of both C26 isoprenoid thiophenes have been unambiguously elucidated by coinjection experiments and comparison of mass spectral data with synthetic standards (45). The first and second eluting isomers (XVIII and XIX respectively, Figure 15) possess a regular (2,6,10,14,18-pentamethylheneicosane) and an irregular (2,6,10,14,19-... 

The loess profile of locality no. 6 at Siitto shows a sandy facies and contains in its upper stratum an Upper Pleistocene interglacial fauna Riss-Wurm"), with a pronouncedly tundra small-mammal fauna 5 m below (Riss-loess , Janossy and Krolopp, 1981). 

Granulite facies calcite from the Hida metamorphic belt, Japan, exhibits one of the best-documented isotope profiles that is at least in part due to diffusional exchange (Wada, 1988 Arita and Wada, 1990 Graham et al., 1998). The marbles are modally dominated by extremely... 

I I Beach facies EZI Black shales Fig. 6. Vertical stratigraphic profile of 5 S and 5 C through the Manjeri Fm. 

In both samples, the presence of a flat-topped Mn profile may reflect the diffusional flattening of an initially bell-shaped compositional profile during high-temperature metamorphism. Volume diffusion of this type is thought to commence in the upper part of the amphibolite facies (Spear 1993). 

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