Coals Carboniferous

The remainder of this paper can be restricted to coals of North America, since this is the area for which we have data and in any case other contributors to this collection will deal with the coals of their own areas. The first statement above needs qualification we ourselves have no liquefaction data on Canadian coals, but Ignasiak et al. (48) present some in this collection.Relying, as in the earlier part of this paper, on geological information, we can say that the strata of the North Great Plains and Rocky Mountain provinces continue north into Canada, as does the Pacific province. Nova Scotia contains some Carboniferous coals related to those in the Eastern province. 

The solubilities thus recorded for 13 Western (Cretaceous) coals (with 69.6-91.5% carbon, daf) and 8 Carboniferous coals (80.6-90.9% C, daf) are shown in Figure 1, and indicate that... 

The Role of Ether-Linkages in Solubilization of Low-Rank Carboniferous Coals by H-Donors... 

Figure 1. Solubilities after treatment with tetrahydronaphthalene at 390°C for 4 hr (----------------), cretaceous coals (-), carboniferous coals.

Figure 13. The difference in length of coaUfication time for coals of the same degree of subsidence Carboniferous coals of the Lower Elbe Trough and Miocene coals of the U.S. Gulf Coast...

Goldhaber, M.B., Hatch, J.R., Pashin, J.C. et al. (1997) Anomalous arsenic and fluorine concentrations in Carboniferous coal, Black Warrior Basin, Alabama evidence for fluid expulsion during Alleghanian thrusting Abstracts with Programs. The Geological Society of America, 29(6), 51. 

Sample Separation and Characterization. Three vitrinite samples (Silkstone, High Hazels, and Westfield) were obtained by hand-picking of macroscopic vitrain bands in Carboniferous coals. Selected vitrain particles were crushed to pass a B. S. 100 mesh sieve (250 y) and polished mounts were prepared. Sample purity was determined by point-counting (sample reflectivity) 500 points, giving a + 2% (by volume) accuracy (18). 

Sporinite samples were prepared from durain bands in preselected Carboniferous coals. Generally, sporinite in durains occurs in intimate mixtures with other macerals, mostly inert inites. To prepare concentrates, the differences in specific gravities between maceral groups were utilized (18) following a float/sink technique modified after Dormans, et. al. (jj. Briefly, small blocks of durain were crushed to pass the B. S. 

The fusinite sample was hand-picked from a discrete fusain lens located within a Carboniferous coal. Microscopical examination of the sample showed that the recovered material contained fusinite, semi-fusinite and mineral matter as the major components. The concentrate was not demineralized. 

Figure 10 Plot of natural gas yields as a function of rank from a European Tertiary coal and a Carboniferous coal from the eastern USA.

Figure 3.7 a. Cumulative gas yield and rate of gas generation for US Carboniferous coals b. Cumulative gas yield and rate of gas generation for German Tertiary coals (after Higgs, 1986, Geological Society Special Publication, no. 23, Figs 4, 8, 10 and 11. Reprinted by permission). 

The gas production layer is a Lower Palaeozoic karstic plateau at a depth of 3000 m, surrounded by palaeo-valleys filled with a Permo-Carboniferous coal series (which could be the source of the natural gas). The annular surface geochemical anomaly may be related to the edge of the buried plateau. In the production layer, the gas is under a pressure of 120 atmospheres. Therefore the average pressure gradient between the gas... 

In order to verify the dynamic concept of the behavior of gas throughout sedimentary basins, we first report the results of an empirical study on The Netherlands offshore gas fields (Broad Fourteens Basin, Fig. 1 shadowed area). This basin is part of the European Upper Carboniferous Basin. The gas fields are sourced from Upper Carboniferous coals and shales, reservoired in Upper Permian Zechstein carbonates (Plattendolomit) and sealed by Zechstein rock salt (Na2-4). The problem facing exploration was that the rate of dry holes was very high even if structural closure and favorable reservoir properties were confirmed. In order to find a solution and to offer a tool for the prediction of fill or non-fill of structures before drilling, we examined 29 case histories (fields, finds, shows and dry holes) under the aspect of dynamics of gas flow. 

In simple terms ash partings are relatively abundant in Cretaceous and Tertiary coals of the West and rare in Carboniferous coals of the East. We are less certain of the Gulf Coast Tertiary lignites but they appear to have at least a moderate abundance of... 

King, H. M.J Renton, J. J., "The Mode of Occurrence and Distribution of Sulfur in West Virginia Coals", Carboniferous Coal Guide Book, (A. Donaldson, M. W. Presley, and J. J. Renton, eds.). West Virginia Geological and Economic Survey Bulletin B-37-1, 1929. 

Schenk H.J., Horsfield B. (1998) Using natural maturation series to evaluate the utility of parallel reaction kinetic models an investigation ofToarcian shales and Carboniferous coals, Germany. Org. Geochem. 29, 137—54. 

Liu OF, Zhang PF, Ding SL, Lin XS, Zheng NX (1996) NH4-illite in Permo-Carboniferous coal-bearing strata. North China. Chin Sci Bull 41 1458-1461... 

Although granular micrinites and semifusinites of Carboniferous coals do not soften and swell when heated, and are therefore classified as un-reactive petrographic components, their equivalents in Cretaceous coals commonly display fairly pronounced plasticity (101,102). Established standard correlations that connect coke stability with the petrographic compositions of Carboniferous coals (103) can consequently not be applied to Cretaceous coals without some modification (104). 

The main coal seams of North China Coalfield (Permo-Carboniferous coal) deposited on the Ordovician limestone, in which the karst was well developed and groundwater was rich. The water head of the underlain Ordovician limestone groundwater gradually increaseand the water pres-... 

The organic constituents of coal (liptinite, inertinite, and huminite/vitrinite) are individually and in combination (microlithotypes) fundamental to many coal properties. Vitrinite is the most common maceral group in many coals, especially in the Carboniferous coals of the Northern Hemisphere, and it is the properties of vitrinite, together with the variations in those properties with rank, that to a large extent determine the properties of the coal concerned. 

ABSTRACT The present mining depth reaches about 600 m and inreases 12 m per year to deep part in key coal mines of eastern North China. Being the basement of coal measure strata in North China coal mine, the Ordovician karst aquifer is the baleful source of water for exploiting the Carboniferous coal bed (deep coal seam). The coal mines that the exploitation transfers into the deep stratum will be threaten by the deep high or superhigh pressure (8-12 MPa) confined water from Ordovician. Meanwhile, the researched area has the Coal Chemical Industry (CCI) which demands a mass of water. This paper analy-sised the current situation of water resources in the researched area and hydraulic, hychemical feature of deep Ordovician fracture-karst aquifer. The concept of Water and Coal Simultaneous Extraction (WCSE) was put forward. The feasibility test of WCSE was put into effect in study area. Einally, the water pressure of deep karst aquifer was reduced for the deep coal mined safely by means of dewatering, which could supply sufficient water for the CCI. 

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