Diagenetic history

To gain an understanding of the composition of the reservoir rock, inter-reservoir seals and the reservoir pore system it is desirable to obtain an undisturbed and continuous reservoir core sample. Cores are also used to establish physical rock properties by direct measurements in a laboratory. They allow description of the depositional environment, sedimentary features and the diagenetic history of the sequence. 

Rocks from 27 boreholes from the Lublin Carboniferous Basin (LCB) were analysed to characterize their mineralogy and diagenetic history (Fig. 1). 

Carbonate sediments deposited in shallow marine environments are often exposed to the influence of meteoric waters during their diagenetic history. Meteoric diagenesis lowers 8 0- and 8 C-values, because meteoric waters have lower 8 0-values than sea water. For example. Hays and Grossman (1991) demonstrated that oxygen isotope compositions of carbonate cements depend on the magnitude of depletion of respective meteoric waters. 5 C-values are lowered because soil bicarbonate is C-depleted relative to ocean water bicarbonate. 

Wherever possible in further analysis of carbonate diagenetic processes, we will consider the diagenetic history of the rocks in light of the framework of plate tectonics. 

Hydrology There are two major factors influencing the distribution of fresh groundwaters on Bermuda (Vacher, 1978). The first is that the limestones of Bermuda represent a lateral succession of stratigraphic units (Figure 7.23 ), rather than a layer-cake arrangement. The second is the diagenetic history of the... 

Beach D.K. (1982) Depositional and diagenetic history of Pleiocene-Pleistocene carbonates of northwestern Great Bahama bank Evolution of a carbonate platform. Ph.D. dissertation, Univ. of Miami, Coral Gables, Florida. 

Mapstone N.B. (1975) Diagenetic history of a North Sea chalk. Sedimentology 22, 601-614. 

Ristvet B.L. (1971) The progressive diagenetic history of Bermuda. In Bermuda Biol. Station for Research Spec. Pub. 9,118-157. 

Wise, S.W., Jr. and Kelts, K.R., 1972. Inferred diagenetic history of a weakly silicified deep sea chalk. Trans. Gulf Coast Assoc. Geol. Soc., 22 177—203. 

A general model which relates fault episodes to the diagenetic history of a basin is also presented. This model may serve as a guide in order to predict fault characteristics (deformation products and style) as well as the possible presence of fault related cementation. Predictions on deformation products are highly relevant when seal evaluations of faults are to be performed. 

Kaiser, W.R. (1984) Predicting reservoir quality and diagenetic history in the Frio Formation (Oligocene) of Texas. In Clastic Diagenesis (Ed. McDonald, D.A. Surdam, R.C.). Mem. Am. Ass. petrol. Geol., Tulsa, 37, 195-216. 

Most diagenetic minerals are the same in the sandstones of the Lower Freshwater Molasse and the Upper Marine Molasse, apd there is no significant difference between the paragenesis of the two units. Minor variations are detected in the diagenetic history preceding the first calcite generation. 

McBride, E.F. (1988) Contrasting diagenetic histories of concretions and host rock. Lion Mountain Sandstone... 

Lundegard, P.d. (1989) Temporal reconstruction of sandstone diagenetic histories. In Burial Diagenesis (Ed. Hutcheon, I.E.). Miner. Ass. Canada Short Course Handbook 15, 161-200. 

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