Matter types

NEXAFS is a useful tool for comparative studies of NOM in the environment. Spectral properties show characteristic fingerprints of organic matter types under investigation. For example, spectra of black carbon exhibit characteristic aromatic... 

These observations can be put on a more chemical basis by examining the variation of AHpp with the atomic hydrogen-to-carbon ratio (Figure 4). Here, the clustering of exinite properties is even more prominent. The single deviant exinite point comes from a very different organic matter type—alginite, rath-... 

Gautier D. L. (1987) Isotopic composition of pyrite relationship to organic matter type and iron availability in some North American Cretaceous shales. Chem. Geol. Isotope Geoset Sect 65, 293-303. 

Hartman-Stroup C. (1987) The effect of organic matter type and organic content on Rock-Eval hydrogen index in oil shales and source rocks. Org. Geochem. 11, 351-369. 

From a geochemical point of view, one of the most important contributions to basin modeling would be the determination of kinetic parameters, followed by characterization of organic matter types. More comprehensive reviews can be found on these topics in articles by Waples (1984, 1994), Hunt (1996), and Welte et al. (1997). 

The direct study of LFCM structure by routine X-ray analysis gives ambiguous results, as far as LFCM themselves are the powerful sources of X-ray radiation, which provides a strong background for detectors. In order to classify at least a condensed matter type (crystalline or amorphous), a temperature dependence of fluidity was measured. Corresponding results are presented in Fig. 1. 

Significant variation in organic geochemistry has been observed within the Whitby Formation and between the Whitby and Kettle Point Formations. Research is in progress to define the geological controls and to relate the resource potential as measured by TOC analyses and FA oil yields to observed variations in organic matter type and maturation level. 

Radke M.,Welte D.H.,Willsch H. (1986) Maturity parameters based on aromatic hydrocarbons Influence of the organic matter type. Org. Geochem. 10, 51-63. 

The onset of primary migration or the oil expulsion threshold is computed taking into account changes in porosity and rock density with depth and time. The critical determination is the threshold porosity Expulsion of liquid hydrocarbons from the source is assumed to commence when the pores become 20% saturated that is, when Pih = 20%. The threshold values for pore saturation are poorly defined and can range from 10 to 60%, depending on the organic matter type (Tissot et al. 1987 Espitalid et al. 1988 Ungerer 1990). 

Davis H. R., Byers C. W. and Dean W. E. (1988) Pyrite formation in the lower Cretaceous Mowry shale effect of organic matter type and reactive iron content. Am. J. Sci. 288, 873 -890. 

Figure I. Elements of a Petroleum System. All petroleum systems contain 1. at least one formation of organic-rich sediments that has been buried to a sufficient depth by overburden rock such that petroleum is generated and expelled, 2. Pathways (permeable strata and faults) that allow the petroleum to migrate, 3. Reservoir rocks with sufficient porosity and permeability to accumulate economically significant quantities of petroleum, and 4. Sealing rock (low permeability) and structures that retain migrated petroleum within the reservoir rock. The top and bottom of the oil window is approximated as a function of burial depth. In actual basins, these depths are not uniform and vary as a function of organic matter type, regional heat flow from basement, in thermal conductivity of the different lithologies, and burial history (e.g., deposition rates, uplift, erosion, and hiatus events).

Hashino, M., Hirami, K., Katagiri, T., Kubota, N., Ohmukai, Y., Ishigami, T., Maruyama, T., and Matsuyama, H. 2011. Effects of three natural organic matter types on cellulose acetate butyrate microfiltration membrane fouling. J. Memb. ScL 379 233-238. 

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