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Organic geochemical analysis, palynology, and PetroMod software for the organic matters of subsurface Tithonian to Valanginian Sulaiy formation of six wells in Basrah Region, South Iraq showed evidences for hydrocarbon generation potential. These analyses include quantitative studies such as pyrolysis, fluorescence spectroscopy, and total organic carbon (TOC), while the qualitative studies are the textural microscopy used in evaluating amorphous organic matter for palynofacies analysis leading to hydrocarbon assessments. High TOC content of up to 7.3 wt.%, kerogen type II of mesoliptinic type with hydrogen index of up to 466 mg HC/g TOC, and mature organic matter along with dysoxic–anoxic environment and stratigraphic framework have rated the succession as a source rock for oil with ordinate gas, not only in Iraq but also in neighboring Kuwait and Saudi Arabia. This case study is also inferred for hydrocarbon generation and expulsion by PetroMod software which confirmed the source potential. 相似文献
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Andrés E. Piatti Ata Sarajedini Doug Geisler Juan Seguel David Clark 《Monthly notices of the Royal Astronomical Society》2005,358(4):1215-1230
Colour–magnitude diagrams (CMDs) are presented for the first time for 10 star clusters projected on to the Small Magellanic Cloud (SMC). The photometry was carried out in the Washington system C and T 1 filters allowing the determination of ages by means of the magnitude difference between the red giant clump and the main-sequence turnoff (MSTO), and metallicities from the red giant branch (RGB) locus. The clusters all have ages in the range 1.5–4 Gyr and metallicities between −1.3 < [Fe/H] < −0.6 , with respective errors of ∼0.5 Gyr and 0.3 dex. This increases substantially the sample of intermediate-age clusters in the SMC with well-derived parameters. We combine our results with those for other clusters in the literature to derive as large and homogeneous a data base as possible (totalling 26 clusters) in order to study global effects. We find evidence for two peaks in the age distribution of SMC clusters, at ∼6.5 and 2.5 Gyr, in good agreement with previous hints involving smaller samples. The most recent peak occurs at a time that corresponds to a very close encounter between the Large Magellanic Cloud (LMC) and the SMC according to the recent dynamical models of Bekki et al. that they used to explain the enhancement of LMC clusters with this age. It appears cluster formation may have been similarly stimulated in the SMC by this encounter as well. We also find very good agreement between cluster ages and metallicities and the prediction from a bursting model from Pagel and Tautvaišienė with a burst that occurred 3 Gyr ago. These two lines of evidence together favour a bursting cluster formation history as opposed to a continuous one for the SMC. 相似文献
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Selahattin Kadir A. Piril Önen-Hall S. Nihal Aydin Cengiz Yakicier Nurten Akarsu Murat Tuncer 《Environmental Geology》2008,54(2):391-409
The Cretaceous-Eocene volcano-sedimentary units of the Zonguldak region of the western Black Sea consist of subalkaline andesite
and tuff, and sandstone dominated by smectite, kaolinite, accessory chlorite, illite, mordenite, and analcime associated with
feldspar, quartz, opal-CT, amphibole, and calcite. Kaolinization, chloritization, sericitization, albitization, Fe–Ti-oxidation,
and the presence of zeolite, epidote, and illite in andesitic rocks and tuffaceous materials developed as a result of the
degradation of a glass shards matrix, enclosed feldspar, and clinopyroxene-type phenocrysts, due to alteration processes.
The association of feldspar and glass with smectite and kaolinite, and the suborientation of feldspar-edged, subparallel kaolinite
plates to fracture axes may exhibit an authigenic smectite or kaolinite. Increased alteration degree upward in which Al, Fe,
and Ti are gained, and Si, Na, K, and Ca are depleted, is due to the alteration following possible diagenesis and hydrothermal
activities. Micromorphologically, fibrous mordenite in the altered units and the presence of needle-type chrysotile in the
residential buildings in which cancer cases lived were detected. In addition, the segregation pattern of cancer susceptibility
in the region strongly suggested an environmental effect and a genetic influence on the increased cancer incidence in the
region. The most likely diagnosis was Li-Fraumeni syndrome, which is one of the hereditary cancer predisposition syndromes;
however, no mutations were observed in the p53 gene, which is the major cause of Li-Fraumeni syndrome. The micromorphology
observed in the altered units in which cancer cases were detected may have a role in the expression of an unidentified gene,
but does not explain alone the occurrence of cancer as a primary cause in the region. 相似文献
15.
Ak&#x;n Kürer Alexandros Chatzipetros Salih Zeki Tutkun Spyros Pavlides
zkan Ate Sotiris Valkaniotis 《Tectonophysics》2008,453(1-4):263
The Yenice–Gönen Fault (YGF) is one of the most important active tectonic structures in the Biga peninsula. On March 18, 1953, a destructive earthquake (Mw = 7.2) occurred on the YGF, which is considered to be a part of the southern branch of the North Anatolian Fault Zone (NAFZ). A 70 km-long dextral surface rupture formed during the Yenice–Gönen Earthquake (YGE).In this study, structural and palaeoseismological features of the YGF have been investigated. The YGF surface ruptures have been mapped and three trenches were excavated at Muratlar, Karaköy and Seyvan sites.According to the palaeoseismic interpretation and the results of 14C AMS dating, Seyvan trench shows that an earthquake of palaeoseismic age ca. 620 AD ruptured a different strand of the 1953 fault, producing rather significant surface rupture displacement, while there are indications that at least two older events occurred during the past millennia. Another set of trenches excavated near Gönen town (Muratlar village) revealed extensive liquefaction not only during the 1953 event, but also during a previous earthquake, dated at 1440 AD. The Karaköy trench shows no indications of recent reactivations.Based on the trenching results, we estimate a recurrence interval of 660 ± 160 years for large morphogenic earthquakes, creating linear surface ruptures. The maximum reported displacement during the 1953 earthquake was 4.2 m. Taking into account the palaeoseismologically determined earthquake recurrence interval and maximum displacement, slip-rate of the YGF has been calculated to be 6.3 mm/a, which is consistent with present-day velocities determined by GPS measurements. According to the geological investigations, cumulative displacement of the YGF is 2.3 km. This palaeoseismological study contributes to model the behaviour of large seismogenic faults in the Biga Peninsula. 相似文献
16.
This paper reports the results of a study of the N-S asymmetry in the flare index using the results of Knoka (1985) combined with our results for the solar cycles 17 to the current cycle 22. By comparing the time-variation of the asymmetry curve with the solar activity variation of the 11-year cycle, we have found that the flare index asymmetry curve is not in phase with the solar cycle and that the asymmetry peaks during solar minimum. A periodic behaviour in the N-S asymmetry appears: the activity in one hemisphere is more important during the ascending part of the cycle whereas during the descending part the activity becomes more important in the other hemisphere. The dominance of flare activity in the southern hemisphere continues during cycle 22 and, according to our findings, this dominance will increase gradually during the following cycle 23. 相似文献
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