ISSN:0141-6421    

DOI:10.1111/j.1747-5457.1984.tb00169.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

ISSN:0141-6421    

DOI:10.1111/j.1747-5457.1984.tb00170.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

Almost all production from Carboniferous formations in the Eastern Hemisphere comes from the Soviet Union, with less importantproduction from the United Kingdom, the Southern North Sea basin, the N W German basin (from the northern Netherlands to Poland), Algeria, Ghana, the Gulf of Suez, China and Australia. However, Carboniferous coals extending from the eastern part of Great Britain to Poland were the source of the hugegas reserves that are found in Permian and Triassic reservoirs in the Southern North Sea‐N W German basin complex. Production of oil during 1978 was approximately 2,680,000 b/dt and of gas, about 20.8 Bcfldf. The USSR share was about 2.6 MM brl and 5.2 Bcf per day. Carboniferous production, which peaked in 1975, has since declined steadily.Most of the USSR's Carboniferous production is from marine carbonates andfrom marine to deltaic sandstones in the Volga‐ Urals, Timan‐Pechora and Dnepr‐Donets basins. The latter basin is mainly gas productive. Smaller amounts of hydrocarbons arepresent in marine beds of the North Caspian (Pricaspian) basin of the European USSR and in similar strata of the Chu‐Sarysu basin of Kazakhstan. Some small, but significant, discoveries have been made in carbonates of the southern part of the West Siberian basin. Although the deep Khuff gas of the Middle East is probably mainly of Permian origin, some Late Carboniferous source materials could have generated part of the gas, inasmuch as the base of the Khuff is probably Late Carboniferous.Hydrocarbons in terrigenous Carboniferous rocks in Egypt are believed to have originated in non‐Carboniferous beds; the petroleum in the Carboniferous sandstone reservoirs of Ghana, China and Australia is generally indigenous, and is non‐marine to deltaic. Oil and gas in the Carboniferous strata of Algeria are in marine and deltaic beds and are partly indigenous. The huge Carboniferous gas reserves in Permian, Triassic and, to a lesser extent, Carboniferous reservoirs of the Southern North Sea‐NW German basin are of non‐marine origin. The source materials were the Upper Carboniferous coals of the same area.The volume of produced Carboniferous oil is about 23 B brl, 21 B brl of it from the Volga‐Urals basin alone. About 63 Tcf of gas has been produced, 51 Tcf from the Southern North Sea‐NW German basin. This volume of gas includes Carboniferous gases in Permian and Triassic reservoirs. Proved and probable reserves of Carboniferous oil are about 13 to 14 B brland 85 Tcf, of which more than 50 Tcf remains in the Netherlands “giant Groningen Barents Sea extensions of the Timan‐Pechora basins, and ‐just possibly ‐ in several Chinese basins. The Arabian Gulf(Persian Gulf) also has a very largegas potential, but thegas, mainly in the Khuff, is of unknown origin and may wellnot be Carboniferous. (The Chu‐Sarysu basin,

ISSN:0141-6421    

DOI:10.1111/j.1747-5457.1984.tb00171.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

The rich vertebrate assemblage recovered from the base of the Köprülü shales at the top of the Devonian Red Sandstones in the Border Folds of SE Turkey has proved to be exceptional in its composition and stratigraphic emplacement. For the first time, several fish species that were previously restricted either to the Late Devonian or to the Early Carboniferous were found together. In association, rich Ostracode assemblages indicate a Strunian (Latest Devonian) age for this fauna and a transition from supratidal to infralittoral environments. Due to the wide distribution of the Devonian‐Carboniferous formations in SE Turkey, Iraq and Iran, this fauna should become a good marker for this major stratigraphical boundary in the Middle

ISSN:0141-6421    

DOI:10.1111/j.1747-5457.1984.tb00172.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

Core samples from Well 33/9‐3, Norwegian North Sea, have been analysed sedimentologically, palynologically and micro‐paleontologically. The cores cover the Toarcian Drake Member of the Dunlin Formation, and nearly the whole thickness of the Middle Jurassic Brent Formation.The Drake Member is characterized by pro‐deltaic depositional conditions. In the Brent Formation, five members are recognized (from below): the Broom, Rannoch and Etive Members represent distributary mouth bar facies; while the Ness and Tarbert Members are recognized as interdistributary bay fill sequences.The composition of the kerogen assemblages is controlled by the changing energy regimes of the different depositional facies. Terrestrial plant débris are dominant throughout the studied interval. Marine palynomorphs are present in the Drake Member and in the lower part of the Broom Member. The development of rich, arenaceous foraminiferal assemblages in the Drake Member are interpreted as a response to shallow, pro‐deltaic conditions. Calcareous foraminifera constitute only a small, accessorial part of these ass

ISSN:0141-6421    

DOI:10.1111/j.1747-5457.1984.tb00173.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

Petrographic and reservoir characteristic studies (porosity and permeability measurements) were carried out on 447 core samples from seven boreholes penetrating concealed unconformities in England and the Western Desert of Iraq. In England, the unconformities occur at the following boundaries: (a) Cretaceous/Devonian; (b) Lower Lias/Rhaeto‐Liassic/Beds of unknown age/Carboniferous Limestone Series; (c)Triassic/Lower Carboniferous; (d) Triassic/Upper Coal Measures (equivalent to Upper Pennsylvanian); and (e) Triassic/Permo‐Trias/Permian. The borehole in the Western Desert of Iraq encountered five unconformities, in successions ranging in age from the Carboniferous to the Cretaceous.The results showed great variations in porosity and permeability in the vicinity of these unconformities. These variations are attributed to diagenetic and epidiagenetic processes which may be summarized as follows: (1) early alteration of unstable components such as feldspars; (2) filling of pores and coating of grains by authigenic clay materials; (3) development of pyramidal or bipyramidal overgrowths on quartz grains; and (4) introduction of late diagenetic poikilotopic sparry calcite and/or dolomite cement.Carbonate rocks are affected by: (1) early dissolution and development of vuggy porosity; (2) dolomitization and dedolomitization; (3) vadose and phreatic cementation; (4) silicification; and (5) modification of porosity and permeability through the growth of new minerals.Finally, on the basis of the results obtained, three models illustrating the evolution of porosity beneath unconformities are propo

ISSN:0141-6421    

DOI:10.1111/j.1747-5457.1984.tb00174.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

Geophysical definition of the three major sedimentary basins of the Ross Sea and scientific drilling on their margins have provided enough information for conceptual models of hydrocarbon generation and source rock character to be applied.The Waples‐Lopatin geochemical model used is an accepted part of preliminary exploration in petroleum frontier areas where data are limited. The model has only a narrow empirical base despite widespread use by the exploration industry, but its value is in the collation and utilization of a variety of parameters which control the physical environment of hydrocarbon generation. This modelling evaluation attempts to overcome the condemnation of a region because of the lack of data rather than the lack of true petroleum potential.In the Ross Sea, the Deep Sea Drilling Project (DSDP) holes 270–273 showed that methane and heavier hydrocarbons are present in the drilled sequences. However, to be significant, they must be indicative of regional generation and not just the result of local anomalies. Modelling shows that there are areas of the Ross Sea where the conditions for hydrocarbon generation should be present and these areas are worthy of future explorat

ISSN:0141-6421    

DOI:10.1111/j.1747-5457.1984.tb00175.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

During the prospectivity analysis of the 40 blocks of the 8th Norwegian round of licensing, a potential “giant” stratigraphic trap was discovered. Its evolutionary histroy makes it especially interesting from a regional point of view.Well information from neighbouring blocks and high quality seismic data has made this possible.In block 16/4 in the southern part of the Viking Graben, a combined stratigraphic/structural trap was formed during the Late Paleocene‐Early Eocene.A submarine fan sequence reached across the viking Graben from the Shetland Platform onto the western flank of the Utsira High of block 16/4 during the Early Paleocene. Later, the Tertiary basins sank with the depo‐centers centered over the old graben. This sinking, together with reactivation of old faults in the southern part of block 16/1 and the northern part of block 16/4 during the Late Paleocene‐Early Eocene, created a large trap. This type of trap is typical for early post‐rift sequences where the post‐rift basin development is governed by the old lines of weakness inherited from the underlying

ISSN:0141-6421    

DOI:10.1111/j.1747-5457.1984.tb00176.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

Book reviewed in this article:Guide to the Petroleum IndustryPetroleum accumulationsOil and Gas YearbookPictures from SpaceEuropean Petroleum Industries Handbook

ISSN:0141-6421    

DOI:10.1111/j.1747-5457.1984.tb00177.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY