bluuebunny/crossref_metadata_2025_split huggingface dataset:
STRATIGRAPHY AND RESERVOIR POTENTIAL OF THE MESOZOIC KHORAT GROUP, NE THAILAND: Part 1: Stratigraphy and Sedimentary Evolution
Authors: Racey A. , Love M.A. , Canham A.C. , Goodall J.G.S. , Polachan S. , Jones P.D. 
Published: December 2007

In this paper, the sedimentology, petrography and biostratigraphy of the Nam Phong Formation and the overlying Mesozoic Khorat Group in NE Thailand are described. Data were gathered during extensive studies in the field (about 100 outcrop localities were investigated) and from laboratory analyses of over 500 surface samples.The Nam Phong Formation is dated accurately for the first time as late Norian to Rhaetian, while the Phra Wihan, Sao Khua, Phu Phan and Khok Kruat Formations (of the Khorat Group) are reassigned to the Early Cretaceous (Berriasian to Aptian) on the basis of new palynological data. The age of the intervening Phu Kradung Formation, which is conventionally assigned to the Lower Jurassic, is probably Late Jurassic or Early Cretaceous, although this cannot be determined with confidence. Changes in provenance between the Nam Phong Formation and the overlying Phu Kradung Formation suggest a possible sedimentary hiatus. Palaeocurrent data suggest that sediments were mainly sourced from the north and east.Part 1 of this paper describes the sedimentology and biostratigraphy of these units; Part 2, which is scheduled to appear in the April, 1996 issue of this Journal, reports on their diagenesis and reservoir quality.
STRATIGRAPHY, SEDIMENTARY ENVIRONMENT AND DEPOSITIONAL EVOLUTION OF THE KHUFF FORMATION IN SOUTH‐CENTRAL SAUDI ARABIA
Authors: Al‐Aswad A. A. 
Published: December 2007

The Upper Permian Khuff Formation, a major gas reservoir unit in Saudi Arabia and other A rabian Gulf countries, has been studied in outcrops south of lat. 23 d̀N in south‐central Saudi Arabia. Fifteen stratigraphic sections were studied and measured; the maximum thickness of the Khuff Formation in this area is about 148m. The formation non‐conformably overlies the Proterozoic rocks of the Arabian Shield here, and the underlying Unayzah Formation is absent due to depositional pinch‐out. The overlying Sudair Shale (Lower Triassic) is found only in small, isolated outliers.The Khuff Formation is composed of alternating sequences of carbonates and siliciclastic rocks, and the proportion of siliciclastics increases southwards. The transgressive Khuff carbonates mark a significant change in the pattern of sedimentation from dominantly siliciclastic to dominantly carbonate. This change is attributed to a combination of factors, all of which acted in favour of carbonate rather than siliciclastic deposition. These factors include a change in the palaeolatitudinal position of the Arabian Plate towards lower latitudes within the subtropical zone; the consequent change inpalaeoclimate towards warmer temperatures; tectonic subsidence associated with the opening of the Neo‐Tethys and closure of the Palaeo‐Tethys Oceans; and the late Early Permian melting of continental glaciers in the area.The major Late Permian marine incursion onto the Arabian Plate resulted in the deposition of extensive carbonates over the Arabian Shelf in a shallow‐marine tidal‐flat system. The shelf was barred, and became differentiated into an inner shelf in the west (where restricted circulation prevailed), and an open‐marine, outer shelf in the east; most sediments were deposited within the photic zone below fairweather wave‐base. The depositional environment changed laterally to the east from a shelf setting to a slope‐and‐basin (with turbidites) in Iran.The sedimentation of the Khuff Formation involved four third‐order depositional cycles, which reflect relative changes in sea‐level. Each cycle began with a transgressive phase, and ended with a regressive phase during which sedimentation occurred in the supratidal zone. The duration of these cycles ranged between 1.33 and 4.08 million yr. Differential tectonic subsidence is invoked to explain these third‐order cycles. The Hail‐Jawf‐Rutbah‐Mosul Arch in the north, and the Hadramaut Arch in the south acted as barriers to the advancing Permian Tethys Sea. The eastern tip of the Arabian Shield was submerged by this transgression.
FUZZY MODELLING AND THE PREDICTION OF POROSITY AND PERMEABILITY FROM THE COMPOSITIONAL AND TEXTURAL ATTRIBUTES OF SANDSTONE
Authors: Fang J. H. , Chen H. C. 
Published: December 2007

A new method is presented here for predicting porosity and permeability from the compositional and textural characteristics of sandstones. The method employs fuzzy modelling which is a linguistic paradigm based on fuzzy logic, rooted in the theory of fuzzy sets. The essentials of fuzzy modelling are explained using an example in which porosity and permeability values of a sandstone are predicted from five compositional and textural attributes. Fuzzy modelling can be accomplished in five steps:

Identification of input and output variables. In this paper, the inputs are five compositional and textural parameters, namely: relative amounts of ductile grains, rigid grains and detrital matrix, to gether with grain size, and the Trask sorting coefficient. The output is either porosity or permeability.
Fuzzy clustering of output values.
Formation of membership grades of input data.
Generation of fuzzy rules; and
Prediction via fuzzy inference.

Compared to statistical modelling (i. e. multiple regression analysis), fuzzy modelling is not only assumption‐free but is also tolerant of outliers. Fuzzy modelling is capable of making both linguistic and numeric predictions based on qualitative knowledge and/ or quantitative data. Thus, fuzzy modelling is not only appropriate for the problem discussed here, but is also desirable for many geological problems characterized by non‐numerical knowledge and imprecise information.
THE ROLE OF OVERPRESSURE IN THE RETARDATION OF ORGANIC MATTER MATURATION
Authors: McTavish R. A. 
Published: December 2007

Abnormal profiles of organic matter maturation in overpressured sequences, which express the retardation of maturation, are a worldwide phenomenon; however, the cause of this retardation has not been explained satisfactorily. Clearly, the different types of pressure in an overpressured regime must be identified in order to determine their role in the retardation of organic matter maturation. Differential pressure is shown to have a marked influence on the maturation of organic matter through its effects on the thermal properties of the source‐rock system.Vitrinite reflectance data from several wells in basins offshore NW Europe have been used to calibrate source‐rock maturation against differential pressure and “effective temperature ” (i.e. observed temperature in an overpressured sequence corrected to the temperature at the same depth in a normally‐pressured sequence). High correlation coefficients with vitrinite reflectance have been measured for both relationships.Differential pressure is a determining factor in porosity reduction. Temperature and porosity affect the thermal conductivity of a rock in both overpressured and normally‐pressured sequences according to established formulae. Cumulative heat flow, the product of observed temperature and thermal conductivity, is an important value which is affected indirectly by differential pressure. A close linear correlation between cumulative heat flow and vitrinite reflectance is proved. Cumulative heat flow can be related to thermodynamic properties of source‐rock systems, and it can be compared to the enthalpy of a system or the internal energy of a reaction. In overpressured sequences, conditions resemble those of constant pressure and constant volume reactions. As a result, cumulative heat flow can be taken as a measure of the final state of a reaction, corresponding in this discussion to the level of vitrinite reflectance. So it can be used as a guide to the state of source‐rock maturation in both normally‐pressured and overpressured sequences.
THE TIMING OF CEMENTATION IN THE ROTLIEGEND SANDSTONES OF THE SOUTHERN NORTH SEA: A PETROLOGICAL AND FLUID INCLUSION STUDY OF CEMENTS
Authors: McNeil B. , Shaw H. F. , Rankin A. H. 
Published: December 2007

We report here on fracture and pore‐filling cements in the Rotliegend Sandstones of the Sole Pit area, UK Southern North Sea. Standard thin‐section petrography and scanning electron microscopy have been complemented by fluid inclusion microthermometry. The main objectives of this paper are to establish the stratigraphy of the sandstones' cements and to describe the cements' characteristics. In addition, the combined use of petrography and fluid inclusion microthermometry is used to define the timing of cementation and gas migration in the Southern North Sea.The geological history of the Sole Pit area is similar to that of other parts of the Southern North Sea. A period of aeolian deposition resulting in the Upper Permian Rotliegend Sandstones was ended by the Zechstein marine transgression. Rapid subsidence followed until Cretaceous times, when a phase of uplift affected the Sole Pit area as well as, for example, the Broad Fourteens Basin. This uplift continued through the Cretaceous and, following a minor phase of subsidence, uplift again took place in the Late Cretaceous and into the Tertiary.When plotted on burial‐thermal history diagrams, the fluid‐inclusion and petrographic results show that quartz cement precipitated over a range of burial depths. Quartz mineralisation was, however, more common at deep burial levels and also during the uplift period in the Sole Pit area, which caused extensive fracturing of the Rotliegend Sandstones. Dolomite precipitation occurred during deep burial diagenesis and ceased largely with the onset of fracturing. Sulphates (anhydrite and barite) were mainly precipitated during the inversion phase in the Sole Pit area. As both the anhydrite fluid inclusions, and possibly also the quartz fluid inclusions within some of these cements contain hydrocarbon gases, the migration of gas took place during the inversion period, using the fractures as migration pathways.
DEPOSITIONAL AND STRUCTURAL DYNAMICS OF THE PLIOCENE PERI‐ADRIATIC FOREDEEP, NE ITALY
Authors: Dattilo P. , Pasi R. , Bertozzi G. 
Published: December 2007

Seismic analyses and detailed well‐log correlations have been used to define the depositional patterns and the relative timing of thrust movements in the highly mobile Peri‐Adriatic Foredeep, a gas‐bearing basin of Pliocene age in NE Italy. Due to the high rates of sedimentation and subsidence, up to 8,000 m of mostly deep‐water clastics were deposited in the foredeep in the Marche‐Abruzzo area during the Pliocene‐early Pleistocene.Three phases of foredeep evolution can be recognised. In the first phase, during which there was little structural activity, a sandy turbidite system of regional dimensions (the Cellino Turbidite System) developed on a flat, stable substratum. Discrete sand‐bodies belonging to this system can be traced over distances of up to 80 km. This turbidite system is a key unit in the analysis of the foredeep. The rapid deposition and burial of organicrich sediments favoured the generation of biogenic gas.The second phase offoredeep evolution coincided with the onset of structural deformation. Sediments are mainly deep‐marine shales and minor turbidite sandstones, which were deposited during a period of almost continuous tectonic activity. A major eastward migration of the deep‐marine depocentre then occurred. In the study area, this phase is represented by a series of closely‐spaced local unconformities which can be correlated eastwards with a major late Pliocene turbidite system. The high frequency of the unconformities is a distinctive feature of this interval.The third phase was characterised by thrusting in the eastern part of the foredeep and by the development of a piggy‐back basin. During this phase, shallow‐water, coarse‐grained deltas replaced the deep‐water turbidite systems. Accommodation space for the coarse‐grained deltas was provided to begin with by rapid subsidence. The progressive decrease in accommodation resulted in delta progradation eastwards and ultimately in the infilling of the foredeep.
BASEMENT LITHOLOGY AND ITS CONTROL ON SEDIMENTATION, TRAP FORMATION AND HYDROCARBON MIGRATION, WIDURI‐INTAN OILFIELDS, SE SUMATRA
Authors: Tonkin P. C. , Himawan R. 
Published: December 2007

The Widuri‐Intan oilfields produce from late Oligocene sandstones of the Talang Akar Formation, which were deposited in a fluvial‐to‐deltaic setting on the NW side of the Asri Basin, offshore SE Sumatra. The Asri Basin is of rift origin and formed during the early Oligocene, with its axis oriented in a NE‐SW direction. Approximately 310 million brls of oil have been produced from the fields within the 12‐by‐12 mile (20‐by‐20 km) study area. The oil occurs in a series of structural and stratigraphic traps within slightly sinuous to meandering channel sandstone bodies. The reservoir sequence (sandstone interbedded with minor mudstone and coal) overlies basement rocks, which are predominantly Cretaceous in age. Forty‐nine well penetrations have shown that the basement is composed of one of four lithologies: (1) hornblende granodiorite; (2) metamorphic rocks, mainly mica schist; (3) plugs of metabasalt and related volcanic rocks; or (4) dolomitic limestone.A combination of drill cuttings, sidewall and conventional cores and FMS/FMI images has been used to identify and map the distribution of basement rock type. The basement was subjected to exposure and deep weathering prior to the formation of the Asri Basin, as evidenced by the zones of surface alteration encountered during drilling. The basement palaeotopography had a strong influence on the later distribution of major fluvial channels and sand pinch‐outs. Several major faults appear to be controlled by basement lithology, especially at the boundaries of granodiorite and metabasalt intrusives. An important shear zone, oriented NW‐SE, appears to have offset the basement between the main Widuri and Intan fields, and was subsequently the site of silicification of the mica schists in the basement. The Lidya field is situated where the reservoir pinches out onto eroded areas of basement silicification along this shear zone. Palaeocurrents in the upper 34–2 and 34–1 channel sandstones in the Widuri field were controlled by the orientation of this basement feature. Drape and compaction of Oligocene Talang Akar Formation sediments over eroded volcanic plugs have defined or enhanced a number of structural/stratigraphic plays, including the Widuri and Chesy fields. From seismic and well evidence, the reservoir sequence at the Indri field is underlain by dolomitic limestone and exhibits a series of unusual karst‐related sinkhole and collapse structures. These are circular to slightly elliptical in shape, and extend from basement level to over 900 ft vertically into the overlying Talang Akar Formation.
RESERVOIR CHARACTERIZATION BY A COMBINED MICRO‐EXTRACTION — MICRO THIN‐LAYER CHROMATOGRAPHY (IATROSCAN) METHOD: A CALIBRATION STUDY WITH EXAMPLES FROM THE NORWEGIAN NORTH SEA
Authors: Bhullar A. G. , Karlsen D. A. , Backer‐Owe K. , Tran K. Le , Skålnes E. , Berchelmann H. H. , Kittelsen J. E. 
Published: December 2007

Well logging is used routinely to delineate variations in the physical properties of the water, gas and oil zones in a petroleum reservoir The analysis of petroleum extracted from reservoir samples is a complementary approach to reservoir screening. For this study, we studied core samples of Jurassic reservoir rock from the Rind discovery (offshore Norway). Bitumen was extracted from these samples using a rapid procedure known as “micro‐extraction”. The extracts were then separated into compound classes (saturated hydrocarbons, aromatic hydrocarbons and polar compounds) by Iatroscan thin‐layer chromatography —flame ionisation detection (TLC‐FID). Using this approach, we show how problematic transition zones in this reservoir, which had not been resolved by logging techniques, were targeted, analysed and categorised. Furthermore, we demonstrate how oil and water zones can be differentiated from residual oil zones, and how the early existence of oil in currently gas‐charged reservoir strata can be inferred. Examples from the Hild, Visund and Ula fields from the Norwegian North Sea illustrate the identification of sand bodies which served as highly interconnected “pipelines” during reservoir filling.The purpose of this paper is to describe and evaluate the combined use of micro‐extraction and Iatroscan TLC‐FID in reservoir screening. We illustrate the application of this dual procedure using case histories from three oilfields and one condensate field in the Norwegian North Sea.
SUPPRESSION AND RETARDATION OF VITRINITE REFLECTANCE, PART 2. DERIVATION AND TESTING OF A KINETIC MODEL FOR SUPPRESSION
Authors: Carr A. D. 
Published: December 2007

The presence of suppressed and retarded vitrinite reflectance (VR) data introduces a number of dificulties into the prediction of hydrocarbon generation in sedimentary basins. Although the effects of suppression can be removed from measured VR values manually, a kinetic model for suppressed vitrinite maturation would enable both suppressed and unsuppressed VR values to be predicted using thermal histories derived from basin modelling. The evaluation of hydrocarbon generation fiom suppressed and unsuppressed vitrinite shows that both have similar reaction kinetics. While hydrocarbon generation involves the rupture of the bonds holding volatiles into the vitrinite structure, increases in VR are mainly produced by aromatisation and condensation reactions which take place after volatiles have been expelled. The reactions involved in hydrocarbon generation are diyerent from those responsible for increases in VR, and it is not therefore appropriate to derive kinetic models of vitrinite maturation from laboratory hydrocarbon generation experiments.During the maturation of normal (unsuppressed) vitrinite, the volatiles generated are expelled via the microporous network; the expulsion efficiency is not limited by the capacity of the microporous network. In hydrogen‐rich (suppressed) vitrinites, excess volatiles saturate the microporous network, restricting further aromatisation and condensation processes within the vitrinite, which results in suppression of VR. Kinetically, this has been modelled by using a variable pre‐exponential or “A” value. Two versions of a kinetic model of vitrinite maturation (SMod‐1 and SMod‐2) have been prepared, based on the amount of suppression predicted by HI‐VR calibration models published by Lo (1993) and Samuels son and Middleton (1998).Two case studies, involving wells Bunga Orkid‐1 (Malay Basin) and 2013–4 (Outer Moray Firth, North Sea), are discussed. Both wells contain suppressed VR values; well 20/3–4 is also overpressured and contains VR data that are both retarded and suppressed. The application of the SMod model to the wells enables heat flow histories derived from tectonic (rift) histories to be used for the prediction of VR data, although in the case of well 20/3–4, the use of a pressure retardation model was also required. Complementary evidence to support the use of the heat flow history applied to well 2013–4 is provided by palaeotemperature data obtained from diagenetic concretions.
REVIEWS
Authors: Frankel S. Herbert 
Published: December 2007

The Study of Society: Metfiods and Problems. Ed. by F. C. BARTLETT, M. GINSBERG, E. J. LINDGREN and R. H. THOULESS.A Century of Social Thought. A series of Lectures Delivered at Duke University during the Academic Year 1938–1939, as a Part of the Centennial Celebration of that Institution.A History of Socialism. By SALLY GRAVES. (Hogarth Press. Pp 308. 5s. Income Tax in the Napoleonic Wars. By ARTHOR HOPE‐JONES. (Cambridge Studies in Economic History. Cambridge University Press 1939.The Theory of Idle Resources. By W. H. HUTT. (Jonathan Cape, 1939.Urban and Rural Housing.(League of Nations, Economic Intelligence Service, Ser. L.O.N.P. 1939. State Banks For India. Being a Study of State Banks and Land Mortgage Credit Institutions in Australia, New Zealand, South Africa, and the United States of America, with suggestions for establishing similar Banks in India, by ANWAR IQBAL QURESHI. (London: Macmfflan and Co. Company Finance. By W. COLLIN BROOKS. (P. S. King & Son, Ltd., 1939. The South African Mints. By E. H. D. ARNDT. (Publication of the University of Pretoria. Series No. Ill: Arts and Social Sciences No. Ons Finansies, Geld–en Bankwese. By. E. H. D. ARNDT. (J. L. Van Schaik, Bepk. 1939.
Vaccination againstPseudomonas aeruginosaPneumonia in Immunocompromised Mice
Authors: Scarff Jennifer M. , Goldberg Joanna B. 
Published: December 2007

ABSTRACTImmunocompromised patients are highly susceptible to infection withPseudomonas aeruginosa. Our laboratory previously showed that intranasal administration of an attenuatedSalmonellastrain expressing theP. aeruginosalipopolysaccharide O antigen was effective in clearing bacteria and preventing mortality in wild-type mice after intranasal challenge. We were interested in investigating the efficacy of this vaccine strategy in immunocompromised mice. Mice rendered leukopenic or neutropenic by intraperitoneal treatment with cyclophosphamide (Cy) or RB6-8C5 antibody, respectively, were more susceptible toP. aeruginosapneumonia than their nontreated counterparts, demonstrating 50% lethal doses several logs lower than that in wild-type mice. This hypersusceptiblity was also associated with bacterial dissemination to the liver and spleen and increased lung permeability in Cy mice. Vaccination of the mice prior to treatment resulted in better survival and lower bacterial loads compared to vector-immunized mice. Although the treatments had no effect on antibody titers, this level of protection was still lower than that seen in untreated vaccinated mice. Administration of antibodies directly to the site of infection at the time of bacterial delivery prolonged survival and lowered bacterial loads in the immunocompromised mice. These results demonstrate the importance of white blood cells while still suggesting a critical role for antibodies in protection againstP. aeruginosainfection.
Stabilization of TM Trimer Interactions during Activation of Moloney Murine Leukemia Virus Env
Authors: Sjöberg Mathilda , Lindqvist Birgitta , Garoff Henrik 
Published: December 2007

ABSTRACT
The transmembrane subunit (TM) of the trimeric retrovirus Env complex is thought to direct virus-cell membrane fusion by refolding into a cell membrane-interacting, extended form that subsequently folds back on itself into a very stable trimer of hairpin-like TM polypeptides. However, so far there is only limited evidence for the formation of a stable TM trimer during Env activation. Here we have studied the oligomer composition and stability of an intermediate and the fully activated form of Moloney murine leukemia virus (Mo-MLV) Env. Activation of Mo-MLV Env is controlled by isomerization of its intersubunit disulfide. This results in surface subunit (SU) dissociation and TM refolding. If activation is done in the presence of an alkylator, this will modify the isomerization-active thiol in the SU of Env and arrest Env at an intermediate stage, the isomerization-arrested state (IAS) of its activation pathway. We generated IAS and fully activated Envs in vitro and in vivo and studied their states of oligomerization by two-dimensional blue native polyacrylamide gel electrophoresis (PAGE) and nonreducing sodium dodecyl sulfate (SDS)-PAGE. The IAS Env was composed of trimers of SU-TM complexes, whereas the activated Env consisted of SU monomers and TM trimers. When the oligomers were subjected to mild SDS treatment the TM trimer was found to be 3.5 times more resistant than the IAS oligomer. Thus, this demonstrates that a structural conversion of TM takes place during activation, which results in the formation of a stable TM trimer.