• Volume 81,Issue 5,2007 Table of Contents
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    • A New Species of Huaxiapterus (Pterosauria: Tapejaridae) from the Early Cretaceous of Western Liaoning, China

      2007, 81(5):683-687.

      Abstract (2789) HTML (0) PDF 3.43 M (810) Comment (0) Favorites

      Abstract:A new species of Huaxiapterus: H. benxiensis sp. nov. is erected based on the new specimen. The diagnostic characters of Huaxiapterus benxiensis are well-developed premaxillary crest and parietal spine, the crest and spine parallel and extending posterodorsally, and a shallow groove present on the dorsal surface of the anterior portion of the mandibular symphysis. The different skull morphologies of Chinese tapejarid pterosaurs indicate that they are much more diverse than the previous thought.

    • First Record of Fossil Mesocupes from China (Coleoptera: Archostemata: Cupedidae)

      2007, 81(5):688-696.

      Abstract (2583) HTML (0) PDF 5.24 M (745) Comment (0) Favorites

      Abstract:Three new fossil species of the genus Mesocupes of fossil cupedids, M. angustilabialis sp. nov., M. latilabialis sp. nov. and M. collaris sp. nov., are described from the Jiulongshan Formation of Inner Mongolia, China. These new species are the first three records of fossil Mesocupes in China as well as the oldest ones in the world now. This finding also extends the geographical distribution of this genus from Central to East Asia. In addition, based on the ratio of the length of the last to the penultimate abdominal ventrites of new beetles distinctly lower than that of the species from the Karabastau Formation, the age of Daohugou fossil-bearing beds might be older than that of Karatau assemblage and consequently of Middle Jurassic.

    • Pathological Microstructure of a Miocene Ostrich Eggshell from Asia

      2007, 81(5):697-702.

      Abstract (2002) HTML (0) PDF 3.97 M (609) Comment (0) Favorites

      Abstract:Struthio linxiaensis is the oldest fossil ostrich from Asia till today. This paper analyzes the microstructure of the eggshell of Struthio linxiaensis. The SEM and light microscopic results show that a pathological structure occurred associated with the formation of pore canal. The feature of this structure is that crystals of the columnar layer are around the lower part of the pore canal, and formed a broad structure. This structure unit contracts upwards more severely than the canal and looks like a "garlic", which was observed in aumiotes eggshells for the first time. Many evidences indicate that this structure was deposited with the columns simultaneously. The radial section view suggests that the "garlic structure" is not a result of antiperistaltic waves in the avian oviduct. The most possible process of the "garlic structure" formation is the column units around the pore canals with imperfect acidifying when calcified, or have some correlations with the changes in the protein profiles of the organic matrix in the calcareous eggshell.

    • A New Enantiornitine Bird with Four Long Rectrices from the Early Cretaceous of Northern Hebei, China

      2007, 81(5):703-708.

      Abstract (2384) HTML (0) PDF 3.94 M (792) Comment (0) Favorites

      Abstract:Paraprotopteryx gracilis, a new enantiornithine bird from the Early Cretaceous Yixian Formation in Fengning, northern Hebei Province is erected, based on the following characters: Yshaped furcula with a long hypocleidum and a much narrow interclavicular angle, and the morphology of the sternum are different from other enantiornithines. Additionally, alular digit bearing the biggest manual claw extends distally to the distal end of the major metacarpal; the minor metacarpal is slender than the major metacarpal. Carpometacarpus only fused proximally; astragalus and calcaneum partially fused to one another but unfused to the tibia. This is the first record of Mesozoic birds in having four long rectrices, which may represent morphologically a secondary sexual character, an intermediate stage from elongated scale to branched feather, and possess functional advantage in supplementing the lifting surface to compensate the unskilled flight.

    • The Tunggurian Stage of the Continental Miocene in China

      2007, 81(5):709-721.

      Abstract (2533) HTML (0) PDF 11.13 M (780) Comment (0) Favorites

      Abstract:The Tunggurian Age was nominated in 1984, and the Second National Commission on Stratigraphy of China formally suggested establishing the corresponding chronostratigraphic unit, the Tunggurian Stage, based on the Tunggurian Age in 1999. The name of this stage comes from a lithostratigraphic unit, the Tunggur Formation, and the stratotype section is located at the Tunggur tableland, 15 km southeast of Saihan Gobi Township, Sonid Left Banner, Inner Mongolia. The Tunggurian Age is correlated to the Astaracian of the European land mammal ages, and they share the same definition of the lower boundary at the base of the paleomagnetic Chron C5Bn.1r with an age of 15.0 Ma. In the Tairum Nor section on the southeastern edge of the Tunggur tableland, this boundary is situated within the successive deposits of reddish-brown massive mudstone of the lower part of the Tunggur Formation, with a distance of 7.6 m from the base of the grayish-white sandstones in the middle part of the section. The Tunggurian is approximately correlated to the upper part of the marine Langhian and the marine Serravallian in the International Stratigraphical Chart. The Tunggurian Stage includes two Neogene mammal faunal units, i.e. NMU 6 (MN 6) and NMU 7 (MN 7/8). The Tairnm Nor fauna from the Talrnm Nor section corresponds to NMU 6, and the Tunggur fauna (senso stricto) from the localities on the northwestern edge of the Tunggur tableland, such as Platybelodon Quarry, Wolf Camp and Moergen, corresponds to NMU 7. Among the Middle Miocene mammalian faunas in China, the Laogou fauna from the Linxia Basin, Gansu, the Quantougou fauna from the Lanzhou Basin, Gansu, the Halamagai fauna from the northern Junggar Basin, Xinjiang, and the Dingjiaergou fauna from Tongxin, Ningxia correspond to NMU 6.

    • Coenotypes in Submerged Paleoforests in the Qianhu Bay, Fujian Province

      2007, 81(5):722-726.

      Abstract (2257) HTML (0) PDF 2.97 M (664) Comment (0) Favorites

      Abstract:The paleoforest remains studied are distributed within a range of 18000 m^2 in the intertidal zone of the Qianhu Bay, Fujian Province. Eighty-nine ancient tree stumps can be clearly recognized in the paleoforest remains. Microscopic studies of 10 relatively low-carbonized stump samples definitely showed four species: Glyptostrobus pensUi (Staunt) Kouch, Schima superba Gardn., Cinnamomum Schaeffer, and Litsea Lam. The 14^C dating of some samples yielded the ages of 42560±350 to 〉43000 a B. P., corresponding to the late Late Pleistocene.

    • Ostracod Biostratigraphy of the Late Cretaceous Qingshankou Formation in the Songliao Basin

      2007, 81(5):727-738.

      Abstract (2803) HTML (0) PDF 9.28 M (734) Comment (0) Favorites

      Abstract:An ostracod biostratigraphic study was performed on 425 samples from the composite geological section constructed by using cores taken from five selected wells drilled in the Late Cretaceous Qingshankou Formation in the Songliao basin. A total of 19 ostracod zones are established in the formation, of which 3 are newly established and 3 are revised. The 19 ostracod zones are described in detail. This study provides a basis for the detailed stratigraphic division and correlation of the Qingshankou Formation and the Gaotaizi oil reservoir in the oilfield in the Songliao basin.

    • From Basin Black Shales to Platform Carbonate Rocks: A Study on Sequence Stratigraphy for the Lower Cambrian of the Upper-Yangtze Region in South China

      2007, 81(5):739-755.

      Abstract (2685) HTML (0) PDF 11.76 M (701) Comment (0) Favorites

      Abstract:

    • Composition and Genesis of Zeolitic Claystones from the Central Indian Ocean Basin

      2007, 81(5):756-770.

      Abstract (2703) HTML (0) PDF 9.69 M (650) Comment (0) Favorites

      Abstract:We examined more than fifty indurated sediments recovered from the Central Indian Ocean Basin (CIOB) during the course of collection for manganese nodules and crusts. The samples occur as slabs either over which ferromanganese oxides are present or over a substrate of altered oceanic basalt in conjunction with palagonite or within the nucleus of manganese nodules. Mineralogically and compositionally, the samples show a mixture of phillipsite, palagonite and montmorillonite. We suggest that the volcanogenic precursors occurring in the CIOB were subjected to varying degrees of alteration under the influence of low temperature conditions, resulting in the formation of zeolitic claystones. The CIOB samples have similarities to those reported from various sites in the world oceans.

    • Daily Variation of Natural Emission of Methane to the Atmosphere and Source Identification in the Luntai Fault Region of the Yakela Condensed Oil/Gas Field in the Tarim Basin, Xinjiang, China

      2007, 81(5):771-778.

      Abstract (2039) HTML (0) PDF 5.90 M (628) Comment (0) Favorites

      Abstract:The static flux chamber method was applied to study natural emissions of methane to the atmosphere in the Luntai fault region of Yakela Condensed Oil/Gas Field in the Tarim Basin, Xinjiang Municipality, northwestern China. Using an online method, which couples together a gas chromatography/high-temperature conversion/isotope ratio mass spectrometry (GC/C/MS), 13^C/12^C ratios of methane in flux chambers were measured and showed that methane gases are liable to migrate from deep oil/gas reservoirs to the surface through fault regions and that a part of the migrated methane, which remains unoxidized can be emitted into the atmosphere. Methane emission rates were found to be highest in the mornings, lowest in the afternoons and then increase gradually in the evenings. Methane emission rates varied dramatically in different locations in the fault region. The highest methane emission rate was 10.96 mg/m^2·d, the lowest 4.38 mg/m^2, and the average 7.55 mg/ m^2·d. The 13^C/12^C ratios of the methane in the flux chambers became heavier as the enclosed methane concentrations increased gradually, which reveals that methane released from the fault region might come from thermogenic methane of the deep condensed oil/gas reservoir.

    • Exploration Potential of Marine Source Rocks Oil-Gas Reservoirs in China

      2007, 81(5):779-797.

      Abstract (2501) HTML (0) PDF 17.10 M (706) Comment (0) Favorites

      Abstract:

    • Control Factors of Solutional Voids in Feldspars and Favorable Zone Forecast of Chang 2 Oil Reservoir Group in the Midwest Ordos Basin

      2007, 81(5):798-804.

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      Abstract:The development of pores in a clastic reservoir is one of the most important research subjects in oil-gas exploration and development, whereas the many reasons for the formation of secondary porosity have increased the degree of difficulty in such research. Thus the research aims are to discover the controlling factors of solutional voids in feldspars and to predict favorable regions for these voids. Macroscopic and systematic researches into the relationship between the kaolinite content in the feldspar solutional void developed area of the Chang 2 reservoir group of the Triassic Yanchang Formation in the Midwest Ordos Basin and the solutional void in feldspar have been made, and from this it can be determined that the kaolinite content has an indicative function to the distribution of the solutional void in feldspar. Solutional void in feldspar is relatively well developed at the area where kaolinite content is high. Although the factors affecting kaolinite content are complicated, yet that of the research area is mainly affected by the impact of the leaching atmospheric water acting on the palaeogeomorphology. Three favorable zone belts for the development of solutional voids in feldspars are forecasted on the basis of restoration of palaeogeomorphology.

    • Formation Mechanism and Controlling Factors of Natural Gas Reservoirs of the Jialingjiang Formation in the East Sichuan Basin

      2007, 81(5):805-816.

      Abstract (2766) HTML (0) PDF 7.28 M (767) Comment (0) Favorites

      Abstract:The Lower Triassic Jialingjiang Formation reservoirs are distributed widely in the East Sichuan Basin, which are composed mainly of fractured reservoirs. However, natural gas with high concentration of H2S, ranging from 4% to 7%, was discovered in the Wolonghe Gas pool consisting primarily of porous reservoirs, while the other over 20 fractured gas reservoirs have comparatively low, tiny and even no H2S within natural gases. Researches have proved the H2S of the above reservoirs are all from the TSR origin. Most of the Jialingjiang Formation natural gases are mainly generated from Lower Permian carbonate rocks, the Wolonghe gas pool's natural gases are from the Upper Permian Longtan Formation, and the natural gases of the Huangcaoxia and Fuchengzhai gas pools are all from Lower Silurian mudstone. The formation of H2S is controlled by the characteristics and temperature of reservoirs, and is not necessarily related with gas sources. The Jialingjiang Formation in East Sichuan is buried deeply and its reservoir temperature has ever attained the condition of the TSR reaction. Due to poor reservoir potential, most of the gas pools do not have enough room for hydrocarbon reaction except for the Wolonghe gas pool, and thus natural gases with high H2S concentration are difficult to be generated abundantly. The south part of East Sichuan did not generate natural gases with high H2S concentration because the reservoir was buried relatively shallow, and did not suffer high temperature. Hence, while predicting the distribution of H2S, the characteristics and temperature of reservoirs are the necessary factors to be considerd besides the existence of anhydrite.

    • A Mathematical Calculation Model Using Biomarkers to Quantitatively Determine the Relative Source Proportion of Mixed Oils

      2007, 81(5):817-826.

      Abstract (2273) HTML (0) PDF 6.13 M (654) Comment (0) Favorites

      Abstract:It is difficult to identify the source(s) of mixed oils from multiple source rocks, and in particular the relative contribution of each source rock. Artificial mixing experiments using typical crude oils and ratios of different biomarkers show that the relative contribution changes are non-linear when two oils with different concentrations of biomarkers mix with each other. This may result in an incorrect conclusion if ratios of biomarkers and a simple binary linear equation are used to calculate the contribution proportion of each end-member to the mixed oil. The changes of biomarker ratios with the mixing proportion of end-member oils in the trinal mixing model are more complex than in the binary mixing model. When four or more oils mix, the contribution proportion of each end-member oil to the mixed oil cannot be calculated using biomarker ratios and a simple formula. Artificial mixing experiments on typical oils reveal that the absolute concentrations of biomarkers in the mixed oil cause a linear change with mixing proportion of each end-member. Mathematical inferences verify such linear changes. Some of the mathematical calculation methods using the absolute concentrations or ratios of biomarkers to quantitatively determine the proportion of each end-member in the mixed oils are deduced from the results of artificial experiments and by theoretical inference. Ratio of two biomarker compounds changes as a hyperbola with the mixing proportion in the binary mixing model, as a hyperboloid in the trinal mixing model, and as a hypersurface when mixing more than three end- members. The mixing proportion of each end-member can be quantitatively determined with these mathematical models, using the absolute concentrations and the ratios of biomarkers. The mathematical calculation model is more economical, convenient, accurate and reliable than conventional artificial mixing methods.

    • Degradation of Tetrachloroethene by Several Co-metabolism Substrates in Groundwater

      2007, 81(5):827-832.

      Abstract (2034) HTML (0) PDF 2.72 M (614) Comment (0) Favorites

      Abstract:Tetrachloroethene (PCE) is biodegraded by reductive dechlorination with co-metabolism substrates under anaerobic conditions. By inoculating sludge from an anaerobic pool, a biodegradation test of PCE is conducted in the anaerobic condition. In the test, several substrates including methanol, ethanol, formate, acetate, lactate and glucose, are conducive to the conversion from PCE to TCE and 1,1-DCE. The results show the microbe can be cultivated well under the anaerobic circumstances of mixture of sewage (sludge) and soil with the index of COD after eleven days. Degradation of PCE accords with one order reaction kinetics equation. The sequence of the reaction rate constant is Kacetate 〉Kglucose 〉 Klactate 〉 Kethanol 〉 Kformate 〉 Kmethanol, and acetate is an outstanding co-metabolism substratum whose reaction rate constant is 0.6632d^-1.

    • Geological Fluid Mapping in the Tongling Area: Implications for the Paleozoic Submarine Hydrothermal System in the Middle-Lower Yangtze Metallogenic Belt, East China

      2007, 81(5):833-860.

      Abstract (2134) HTML (0) PDF 20.71 M (641) Comment (0) Favorites

      Abstract:

    • Sedimentary Characteristics and Paleoenvironmental Records of Zabuye Salt Lake, Tibetan Plateau, since 128 ka BP

      2007, 81(5):861-874.

      Abstract (2819) HTML (0) PDF 8.84 M (862) Comment (0) Favorites

      Abstract:This paper for the first time reveals high-resolution core records of Zabuye Salt Lake in the interior of the Qinghai-Tibet Plateau. According to 1346 samples taken continuously, relatively accurate 14^C, U-series disequilibrium and ESR ages have been obtained, thus revealing that the lake core ages from 0 to 83.63 m of hole SZK02 are -800 to over 128 ka. In the paper, the lake core sedimentary characteristics (including the lithologies and mineral assemblages) are analyzed in detail and correlated with ostracod assemblages I to XX and sporopollen zones A to I, and on the basis of an integrated analysis of the δ^18O values of authigenic calcium-magnesium carbonate and environmental proxies of minerals, sporopollen and microfossils in the lake core, a correlation has been made of oxygen isotope change between this lake core and the Greenland GISP2 and GRIP and Guliya ice cores, and the climate of Zabuye Salt Lake since 128 ka BP is divided into the last interglacial stage (including substages e, d, c, b and a) of oxygen isotope stage (OIS) 5, early glacial stadial of the last glacial stage of OIS 4, interglacial stadial of the last glacial stage of OIS 3, late glacial stadial of the last glacial stage or Last Glacial Maximum of OIS 2 and postglacial state of OIS 1; in addition, 6 Heinrich (H6-H1) events, Younger Dryas event and 8.2 ka BP cold event have been recognized.

Chief Editor:HOU Zengqian

Governing Body:China Association for Science and Technology

Organizer:Geological Society of China

start publication :1922

ISSN:ISSN 1000-9515

CN:CN 11-2001/P

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