Abstract:Shansisuchus shansisuchus Young, 1964 was restudied on the basis of a new specimen. Some anatomical features that were either briefly or not described at all in the original study were detailed. The new specimen not only provides further information on the skull anatomy and the vertebral column but also expands the range of the geographical distribution of the taxon. With new information, the diagnosis of S. shansisuchus was emended and its phylogenetic relationships were further analyzed. S. shansisuchus differs from other archosauriforms primarily in the presence of a large subnarial fenestra anterior to the antorbital fenestra, tongue-in-groove articulations between the ascending process of the premaxilla and nasal and between the premaxilla and maxilla, a tall and posterodorsally directed ascending process of the maxilla, a knee-shaped process of the postorbital projecting into the orbit, a broad descending process of squamosal distally well forked and a large, deeply bow-shaped intercentrum tightly anchoring/capping the sharp ventral edges of two neighboring centra together in cervical and at least first eight dorsal vertebrae. With additional information derived from the new specimen, the phylogenetic relationships of S. shansisuchus were reanalyzed; it is closely related to Erythrosuchus-Vjushkovia clade.

Abstract:Pterosaur bones are for the first time reported from the Tremp Syncline (Spain) and the southern Pyrenees. They come from the Torrebilles-2 site (Isona, Lleida Province) in the upper Maastrichtian part of the Tremp Formation, which falls within the C29r magnetochron. Fragmentary long bones are referred to the Pterosauria based on their cortical thinness, micro-architecture, and histological features. They belong to very large to possibly giant individuals. The most complete specimen is possibly a partial right femur. The review of the Maastrichtian pterosaur record shows that only a few specimens can be referred to the C29r (which contains the K/Pg boundary). The identification of fragmentary remains could improve our knowledge about the abundance and distribution of these flying sauropsids just before the end-Cretaceous mass extinction.

Abstract:The Axymyiidae is one of the small families of the suborder Nematocera within the Diptera. Up to date, three genera and seven species of extant axymyiids have been described from the Holarctic Region, including Canada, China, Hungary, Japan, Russia, and USA, with three genera and three species of fossil taxa described from the Middle Jurassic of Daohugou, northeastern China. A new genus Raraxymyia gen. nov. and two new species, R. parallela and R. proxima gen. et sp. nov. from the Middle Jurassic Jiulongshan Formation of Daohugou Village, Inner Mongolia, China, are herein described based on their well-preserved wings and body characters. A revised key to the genera of axymyiids is provided.

Abstract:The family Mesopsychidae Tillyard, 1917 presently consists of ten described genera from the Early Permian to the Early Cretaceous of Australia, China, Kyrgyzstan, Russia, South Africa, Tajikistan, and Ukraine. Herein, a new genus and a new species of fossil mesopsychid, Epicharmesopsyche pentavenulosa gen. et sp. nov., is described from the Middle Jurassic Jiulongshan Formation of Inner Mongolia, China, supplementing the family-level diversity. The well-preserved, new material reveals many characters, including antennae, wing venation, shape and genitalia that increase our morphological understanding of the family, although unfortunately the mouthparts and most of the legs are not preserved. Diagnosis of the Mesopsychidae is emended to include a four- or five-branched MP in both the fore- and hind wings. This is the first documentation of a wing coupling structure in the Mesopsychidae, consisting of three to four frenula bristles on the humeral lobe at the base of the costal margin of both hind wings. Asymmetrical shape and size of the left and right wings on a specimen of E. pentavenulosa gen. et sp. nov., seems to be a common condition for mesopsychid taxa from northeastern China.

Abstract:Three Schizolepis species collected from the Lower Cretaceous layer of the Huolinhe Basin, Inner Mongolia, China are described. These fossils are Schizolepis longipetiolus Xu XH et Sun BN sp. nov., which is a new species, Schizolepis cf. heilongjiangensis Zheng et Zhang, and Schizolepis neimengensis Deng. The new species is a well-preserved female cone, slender and cylindrical in shape. The seed–scale complexes have long petioles and are arranged on the cone axis loosely and helically. The seed scales are divided into two lobes from the base. Each lobe is semicircular or elongate ligulate in shape, widest at the middle or the lower middle part, with an obtuse or bluntly pointed apex. The inner margin is almost straight and the outer margin is strongly arched. On the surface of the lobe, there are longitudinal and somewhat radial striations from the base to the margin. The seed is borne on the adaxial surface at the base or middle of each lobe. Schizolepis was established in 1847, and, although more than twenty species have been discovered and reported, its phylogenetic position is controversial because of the imperfection of fossils. Most authors have considered there to be a close evolutionary relationship between Schizolepis and extant Pinaceae. Here, we analyze characteristics and compare Schizolepis with Picea crassifolia Kom, which is morphologically most similar to Schizolepis. The results indicate that the genus probably has a distant evolutionary relationship with extant Pinaceae. A detailed statistical analysis of the global paleogeographic distribution of Schizolepis showed that all the fossils of this genus appeared in strata ranging from the Upper Triassic to the Lower Cretaceous in the North Hemisphere, being rare in the Upper Triassic and Lower Jurassic, but being very common from the Middle Jurassic to the Lower Cretaceous, and particularly abundant in the Lower Cretaceous. According to the statistical results, we speculate that the genus originated in Europe in the Late Triassic then spread from Europe to Asia between the Late Triassic and the Late Jurassic. In the Early Cretaceous most species existed in China’s three northeastern Provinces and the Inner Mongolia Autonomous Region and adjacent areas. Combining the paleogeographic distribution of the genus with ancient climatic factors, we deduced that Schizolepis began to decline and became extinct in the Early Cretaceous, and the reason for its extinction is closely related to the icehouse climate during the Early Cretaceous.

Abstract:A biostratigraphic study on calcareous nannofossils from the CM3D06 Co-rich ferromanganese crust from the Magellan seamounts in the northwestern Pacific enabled estimation of depositional age. The bio-imprinting of calcareous nannofossils and other fossil species suggests six age ranges for the nannofossils: late Cretaceous, late Paleocene, (early, middle, late) Eocene, middle Miocene, late Pliocene, and Pleistocene. Gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS) were used to test the Co-rich crusts, and a variety of molecular fossils were detected, such as chloroform bituminous “A” , n-alkane, isoprenoid and sterol. Peak carbon and molecular indices (such as ΣC23?/ΣC24+, CPI, Pr/Ph, Pr/nC17, Ph/nC18 and δ13C) indicate that the parent organic matter is dominated by marine phytoplankton and thallogen whereas there is little input of terrestrial organic matter. Researches on calcareous nannofossils, molecular fossils and molecular organic geochemistry data reveal that the Paleocene/Eocene (P/E) global event is recorded in the cobalt-rich crusts from the northwestern Pacific Ocean. A succession of biomes can be observed near the 85 mm boundary (about 55 Ma), i.e., the disappearance of the late Cretaceous Watznaueria barnesae and Zigodicus spiralis, and Broisonia parka microbiotas above the P/E boundary, and the bloom of Coccolithus formosus, Discoaster multiradiatus, Discoaster mohleri and Discoaster sp. below the boundary. Typical parameters of molecular fossils, such as saturated hydrocarbon components and carbon-number maxima, Pr/Ph, Pr/C17, Ph/C18, distribution types of sterols, Ts/Tm ratios and bacterial hopane, also exhibit dramatic changes near the P/E boundary. These integrated results illustrate that the biome succession of calcareous nannofossils, relative content of molecular fossils and molecular indices in the cobalt-rich crusts near the 85 mm boundary faithfully record the P/E global event.

Abstract:We describe the new mineral species titanium, ideally Ti, found in the podiform chromitites of the Luobusha ophiolite in Tibet, People’s Republic of China. The irregular crystals range from 0.1 to 0.6 mm in diameter and form an intergrowth with coesite and kyanite. Titanium is silver grey in colour, the luster is metallic, it is opaque, the streak is grayish black, and it is non-fluorescent. The mineral is malleable, has a rough to hackly fracture and has no apparent cleavage. The estimated Mohs hardness is 4, and the calculated density is 4.503 g/cm3. The composition is Ti 99.23-100.00 wt%. The mineral is hexagonal, space group P63/mmc. Unit-cell parameters are a 2.950 (2) ?, c 4.686 (1) ?,V 35.32 ( 5) ?3, Z = 2. The five strongest powder diffraction lines [d in ? (hkl) (I/I0)] are: 2.569 (010) (32), 2.254(011) (100), 1.730 (012) (16), 1.478 (110) (21), and 0.9464 (121) (8). The species and name were approved by the CNMNC (IMA 2010–044).

Abstract:The Neogene-Quaternary Harrat Rahat volcanic field is part of the major intercontinental Harrat fields in western Saudi Arabia. It comprises lava flows of olivine basalt and hawaiite, in addition to mugearite, benmorite, and trachyte that occur mainly as domes, tuff cones and lava flows. Based on opaque mineralogy and mineral chemistry, the Harrat Rahat volcanic varieties are distinguished into Group I (olivine basalt and hawaiite) and Group II (mugearite, benmorite and trachyte). The maximum forsterite content (~85) is encountered in zoned forsteritic olivine of Group I, whereas olivine of Group II is characterized by intermediate (Fo=50), fayalitic (Fo=25) and pure fayalite in the mugearite, benmorite and trachyte, respectively. The more evolved varieties of Group II contain minerals that show enrichment of Fe2+, Mn2+ and Na+ that indicates normal fractional crystallization. The common occurrence of coarse apatite with titanomagnetite in the benmorite indicates that P5+ becomes saturated in this rock variety and drops again in trachyte. Cr-spinel is recorded in Group I varieties only and the Cr# (0.5) suggests lherzolite as a possible restite of the Harrat Rahat volcanics. The plots of Cr# vs. the forsterite content (Fo) suggest two distinct trends, which are typical of mixing of two basaltic magmas of different sources and different degrees of partial melting. The bimodality of Harrat Rahat Cr-spinel suggests possible derivation from recycled MORB slab in the mantle as indicated by the presence of high-Al spinel. It is believed that the subcontinental lithospheric mantle was modified by pervious subduction process and played the leading role in the genesis of the Harrat Rahat intraplate volcanics. The trachytes of the Harrat Rahat volcanic field were formed most probably by melting of a lower crust at the mantle-crust boundary. The increase in fO2 causes a decrease in Cr2O3, and Al2O3, and a strong increase in the proportion of Fe3+ and Mg# of spinel crystallizing from the basaltic melt at T ~1200°C. The olivine-pyroxene and olivine-spinel geothermometers yielded equilibrium temperature in the range of 935-1025°C, whereas the range of <500-850°C from single-pyroxene thermometry indicates either post crystallization re-equilibrium of the clinopyroxene, or the mineral is xenocrystic and re-equilibrated in a cooling basaltic magma.

Abstract:An extensive suite of igneous sills was intruded into the Tertiary sedimentary section of the Jiaojiang sag, East China Sea. This suite has been well imaged offshore through 2D and 3D seismic surveys, showing a close relationship with CO2 content in nearby gas discoveries. A new observational model, which incorporates simple upward propagation, simple horizontal propagation, and transgressive propagation, was proposed to interpret these sill intrusions. In this model, the source magma of the saucer-shaped sills was injected from their lowest points near the center. The transgressive propagation can be interpreted as a combination of the vertical and horizontal propagation. Most shallow sub-volcanic intrusions in the Jiaojiang sag exhibit fingered characteristics, both vertically and horizontally. The vertical fingered propagation produced saucer-shaped sills arranged in the flower style. Along the brims of lower sills could usually be found the upper sills, which are interpreted to have formed simultaneously with or later than the lower feeder sills. In the second type, the chilled paths of the older sills were reutilized by subsequent intrusions. The horizontal fingered propagation formed sheet intrusions that exhibit groove, lobate, tubular, and crevasse splay-like geometry in plan view. In 3D view, the sheet intrusions have still preserved the lower center and higher rim that similar with the sub-rounded saucer-shaped sills. Although fracture propagation may be important, flow inflation was the key mechanism of magma intrusion. Further consideration of the mechanisms underlying sill formation may help explain the fingered characteristics of sill propagation.

Abstract:The Kekekete mafic-ultramafic rocks are exposed in the Kekesha-Kekekete-Dawate area, which are in the eastern part of the East Kunlun Orogenic Belt. It outcrops as tectonic slices intruding tectonically in the Paleoproterozoic Baishahe Group and the Paleozoic Nachitai Group. The Kekekete mafic and ultramafic rocks is located near the central fault in East Kunlun and lithologically mainly consists of serpentinite, augite peridotite, and gabbro. The LA-ICP-MS zircon U-Pb age of the gabbro is 501±7 Ma, indicating that Kekekete mafic-ultramafic rocks formed in the Middle Cambrian. This rock assemblage is relatively poor in SiO2 and (Na2O+K2O) but rich in MgO and SFeO. The chondrite-normalized REE patterns of the gabbro dip slightly to the right; the primitive mantle and MORB-normalized spidergrams of trace elements show enrichment of large-ion lithophile elements (Cs, Rb, Ba, etc.) and no differentiation of high field strength elements. The general dominance of E-MORB features and the geochemical characteristics of OIB suggest that the Kekekete mafic-ultramafic rocks formed in an initial oceanic basin with slightly enriched mantle being featured by varying degrees of mixing of N-MORB depleted mantle and a similar-OIB-type source. From a comprehensive study of the previous data, the author believes that the tectonic history of the East Kunlun region was controlled by a geodynamic system of rifting and extension in the late stages of the Neoproterozoic to early stages of the Early Paleozoic and this formed the paleo-oceanic basin or rift system now represented by the ophiolites along the central fault in East Kunlun, the Kekekete mafic-ultramafic rocks and Delisitan ophiolite.

Abstract:The Nage Cu-Pb deposit, a new found ore deposit in the southeast Guizhou province, southwest China, is located on the southwestern margin of the Jiangnan Orogenic Belt. Ore bodies are hosted in slate and phyllite of Neoproterozoic Jialu and Wuye Formations, and are structurally controlled by EW-trending fault. It contains Cu and Pb metals about 0.12 million tonnes with grades of 0.2 wt% to 3.4 wt% Cu and 1.1 wt% to 9.27 wt% Pb. Massive and disseminated Cu-Pb ores from the Nage deposit occur as either veinlets or disseminations in silicified rocks. The ore minerals include chalcopyrite, galena and pyrite, and gangue minerals are quartz, sericite and chlorite. The H-O isotopic compositions of quartz, S-Cu-Pb isotopic compositions of sulfide minerals, Pb isotopic compositions of whole rocks and ores have been analyzed to trace the sources of ore-forming fluids and metals for the Nage Cu-Pb deposit. The δ65CuNBS values of chalcopyrite range from -0.09% to +0.33‰, similar to basic igneous rocks and chalcopyrite from magmatic deposits. δ65CuNBS values of chalcopyrite from the early, middle and final mineralization stages show an increasing trend due to 63Cu prior migrated in gas phase when fluids exsolution from magma. δ34SCDT values of sulfide minerals range from ?2.7‰ to +2.8‰, similar to mantle-derived sulfur (0±3‰). The positive correlation between δ65CuNBS and δ34SCDT values of chalcopyrite indicates that a common source of copper metal and sulfur from magma. δDH2O-SMOW and δ18OH2O-SMOW values of water in fluid inclusions of quartz range from ?60.7‰ to ?44.4‰ and +7.9‰ to +9.0‰ (T=260°C), respectively and fall in the field for magmatic and metamorphic waters, implicating that mixed sources for H2O in hydrothermal fluids. Ores and sulfide minerals have a small range of Pb isotopic compositions (208Pb/204Pb=38.152 to 38.384, 207Pb/204Pb=15.656 to 17.708 and 206Pb/204Pb=17.991 to 18.049) that are close to orogenic belt and upper crust Pb evolution curve, and similar to Neoproterozoic host rocks (208Pb/204Pb=38.201 to 38.6373, 207Pb/204Pb=15.648 to 15.673 and 206Pb/204Pb=17.820 to 18.258), but higher than diabase (208Pb/204Pb=37.830 to 38.012, 207Pb/204Pb=15.620 to 15.635 and 206Pb/204Pb=17.808 to 17.902). These results imply that the Pb metal originated mainly from host rocks. The H-O-S-Cu-Pb isotopes tegather with geology, indicating that the ore genesis of the Nage Cu-Pb deposit is post-magmatic hydrothermal type.

Abstract:Surface lake sediments, 28 from Hoh Xil, 24 from northeastern China, 99 from Lake Bosten, 31 from Ulungur and 26 from Heihai were collected to determine δ13C and δ18O values. Considering the impact factors, conductivity, alkalinity, pH, TOC, C/N and carbonate-content in the sediments, Cl, P, S, and metal element ratios of Mg/Ca, Sr/Ca, Fe/Mn of bulk sediments as environmental variables enable evaluation of their influences on δ13C and δ18O using principal component analysis (PCA) method. The closure and residence time of lakes can influence the correlation between δ13C and δ18O. Lake water will change from fresh to brackish with increasing reduction and eutrophication effects. Mg/Ca in the bulk sediment indicates the characteristic of residence time, Sr/Ca and Fe/Mn infer the salinity of lakes. Carbonate formation processes and types can influence the δ13C–δ18O correlation. δ18O will be heavier from Mg-calcite and aragonite formed in a high-salinity water body than calcite formed in freshwater conditions. When carbonate content is less than 30%, there is no relationship with either δ13C or δ18O, and also none between δ13C and δ18O. More than 30%, carbonate content, however, co-varies highly to δ13C and δ18O, and there is also a high correlation between δ13C and δ18O. Vegetation conditions and primary productivity of lakes can influence the characteristics of δ13C and δ18O, and their co-variance. Total organic matter content (TOC) in the sediments is higher with more terrestrial and submerged plants infilling. In northeastern and northwestern China, when organic matter in the lake sediments comes from endogenous floating organisms and algae, the δ13C value is high. δ13C is in the range of ?4‰ to 0‰ when organic matter comes mainly from floating organisms (C/N<6); in the range of ?4‰ to 8‰ when organic matter comes from diatoms (C/N=6 to 8); and ?8‰ to ?4‰ when organic matter comes from aquatic and terrestrial plants (C/N>8).

Abstract:The Jinshachang lead–zinc deposit is mainly hosted in the Upper Neoproterozoic carbonate rocks of the Dengying Group and located in the Sichuan–Yunnan–Guizhou (SYG) Pb–Zn–Ag multi-metal mineralization area in China. Sulfides minerals including sphalerite, galena and pyrite postdate or coprecipitate with gangue mainly consisting of fluorite, quartz, and barite, making this deposit distinct from most lead–zinc deposits in the SYG. This deposit is controlled by tectonic structures, and most mineralization is located along or near faults zones. Emeishan basalts near the ore district might have contributed to the formation of orebodies. The δ34S values of sphalerite, galena, pyrite and barite were estimated to be 3.6‰–13.4‰, 3.7‰–9.0‰, ?6.4‰ to 29.2‰ and 32.1‰–34.7‰, respectively. In view of the similar δ34S values of barite and sulfates being from the Cambrian strata, the sulfur of barite was likely derived from the Cambrian strata. The homogenization temperatures (T ≈ 134–383°C) of fluid inclusions were not suitable for reducing bacteria, therefore, the bacterial sulfate reduction could not have been an efficient path to generate reduced sulfur in this district. Although thermochemical sulfate reduction process had contributed to the production of reduced sulfur, it was not the main mechanism. Considering other aspects, it can be suggested that sulfur of sulfides should have been derived from magmatic activities. The δ34S values of sphalerite were found to be higher than those of coexisting galena. The equilibrium temperatures calculated by using the sulfur isotopic composition of mineral pairs matched well with the homogenization temperature of fluid inclusions, suggesting that the sulfur isotopic composition in ore-forming fluids had reached a partial equilibrium.

Abstract:Five Paleogene volcanics sampled from the northern South China Sea were analyzed via LA-ICP-MS zircon U-Pb dating, including basalt and andesite from Borehole SCSV1 and volcanic agglomerate from Borehole SCSV2, respectively. A total of 162 zircon U-Pb dates for them cover an age range from Neoarchean to Eocene, in which the pre-Paleocene data dominate. The Paleogene dates of 62.5±2.2 Ma and 42.1±2.9 Ma are associated with two igneous episodes prior to opening of South China Sea basin. Those pre-Paleocene zircons are inherited zircons mostly with magmatogenic oscillatory zones, and have REE features of crustal zircon. Zircon U-Pb dates of 2518–2481 Ma, 1933–1724 Ma, and 1094–1040 Ma from the SCSV1 volcanics, and 2810–2718 Ma, 2458–2421 Ma, and 1850–993.4 Ma from the SCSV2 volcanics reveal part of Precambrian evolution of the northern South China Sea, well comparable with age records dated from the Cathaysia block. The data of 927.0±6.9 Ma and 781±38 Ma dated from the SCSV2 coincide with amalgamation between Yangtze and Cathaysia blocks and breakup of the Rodinia, respectively. The age records of Caledonian orogeny from the Cathaysia block are widely found from our volcanic samples with concordant mean ages of 432.0±5.8 Ma from the SCSV1 and of 437±15 Ma from the SCSV2. The part of the northern South China Sea resembling the Cathaysia underwent Indosinian and Yanshannian tectonothermal events. Their age signatures from the SCSV1 cover 266.5±3.5 Ma, 241.1±6.0 Ma, 184.0±4.2 Ma, 160.9±4.2 Ma and 102.8±2.6 Ma, and from the SCSV2 are 244±15 Ma, 158.1±3.5 Ma, 141±13 Ma and 96.3±2.1 Ma. Our pre-Paleogene U-Pb age spectra of zircons from the borehole volcanics indicate that the northern South China Sea underwent an evolution from formation of Precambrian basement, Caledonian orogeny, and Indosinian orogeny to Yanshannian magmatism. This process can be well comparable with the tectonic evolution of South China, largely supporting the areas of the northern South China Sea as part of southward extension of the Cathaysia.

Abstract:BSR (Bottom Simulating Reflector) occurs widely in the strata since the late Miocene in the deep-water area of the northern continental slope of South China Sea (SCS). It is an important seismic reference mark which identifies the gas hydrate and its distribution influenced by the tectonic movements. Single-point basin modeling was conducted using 473 points in the study area. To discuss the relationships between the tectonic subsidence and BSR, the volume and rate of tectonic subsidence in each geological time have been simulated. The results show that there are three tectonic accelerate subsidence processes in the study area since the late Miocene, especially since 1.8Ma the tectonic subsidence accelerates more apparently. Since the Late Miocene to Pleistocene, the rate of tectonic subsidence in deep-water underwent a transformation from weak to strong. The ratio of tectonic subsidence to the total subsidence was relatively high (65-70%). Through the superposition of the BSR developed areas and the contours of tectonic subsidence in this area, it was discovered that more than 80% of BSR tend to be distributed at the slope break or depression-uplift structural transfer zone and the average tectonic subsidence rate ranges from 70 m/Ma to 125 m/Ma.

Abstract:Monitoring and sampling of main plants, soil CO2, soil water, bedrock, spring water, drip water and its corresponding speleothem were performed at four cave systems of Guizhou, Southwest China, from April 2003 to May 2004, in order to understand stable carbon isotope ratios variations of dissolved inorganic Carbon (DIC) in cave percolation waters (δ13CDIC) and their implications for paleoclimate. Stable carbon isotopic compositions and ions (Ca, Mg, Sr, SO4, Cl etc.) were measured for all samples. The results indicate that there are significant differences among the δ13CDIC values from inter-cave, even inter-drip of intra-cave in the four caves. The δ13CDIC values from the Liangfeng Cave (LFC) is lightest among the four caves, where vegetation type overlying the cave is primary forest dominated by tall trees with lighter average δ13C value (–29.9‰). And there are remarkable differences in δ13CDIC values of different drip waters in the Qixing Cave (QXC) and Jiangjun Cave (JJC), up to 6.9‰ and 7.8‰, respectively. Further analyses show that the δ13CDIC values in cave drip waters are not only controlled by vegetation biomass overlying the cave, but also hydro-geochemical processes. Therefore, accurate interpreting of δ13C recorded in speleothems cannot be guaranteed if these effects of the above mentioned factors are not taken into consideration.

Abstract:A method is proposed to predict the flowing bottomhole pressures (FBHPs) for two-phase coalbed methane (CBM) wells. The mathematical models for both gas column pressure and two-phase fluid column pressure were developed based on the well liquid flow equation. FBHPs during the production were predicted by considering the effect of entrained liquid on gravitational gradients. Comparison of calculated BHPs by Cullender-Smith and proposed method was also studied. The results show that the proposed algorithm gives the desired accuracy of calculating BHPs in the low-productivity and low-pressure CBM wells. FBHP is resulted from the combined action of wellhead pressure, gas column pressure and fluid column pressure. Variation of kinetic energy term, compressibility and friction factors with depth increments and liquid holdup with velocity should be considered to simulate the real BHPs adequately. BHP is a function of depth of each column segment. The small errors of less than 1.5% between the calculated and measured values are obtained with each segment within 25?m. Adjusting BHPs can effectively increase production pressure drop, which is beneficial to CBM desorption and enhances reservoir productivity. The increment of pressure drop from 5.37 MPa2 to 8.66 MPa2 leads to an increase of CBM production from 3270 m3/d to 6700 m3/d and is attributed to a decrease in BHP from 2.25 MPa to 1.33 MPa.

Abstract:The aim of the present study is to locate and decipher the groundwater quality, types, and hydrogeochemical reactions, which are responsible for elevated concentration of fluoride in the Chhindwara district in Madhya Pradesh, India. Groundwater samples, quality data and other ancillary information were collected for 26 villages in the Chhindwara District, M.P. India during May 2006. The saturation index was computed for the selected samples in the region, which suggest that generally most of the minerals are saturated with respect to water. The concentration of fluoride in the region varies from 0.6 to 4.74 mg/l, which is much higher as per the national and international water quality standards. The study also reveals that the fluoride bearing rock formations are the main source of the higher concentration of fluoride in groundwater along with the conjuncture of land use change. Moreover, the area is a hard rock terrain and consists of fractured granites and amygdaloidal and highly jointed compact basalt acting as good aquifer, which is probably enriching the high content of fluoride in groundwater. High concentration of fluoride is found in deeper level of groundwater and it is possible due to rock-water interaction, which requires further detailed investigation. The highly alkaline conditions indicate fluorite dissolution, which works as a major process for higher concentration of fluoride in the study area. The results of this study will ultimately help in the identification of risk areas and taking measures to mitigate negative impacts related to fluoride pollution and toxicity.

Abstract:Trace metal concentrations were investigated in a recent sediment core collected from the Rehri Creek area of the Karachi coast, Sindh - Pakistan. The core was sliced horizontally at 2.5-cm intervals to determine grain size, sediment composition, pH, organic matter, and acid-leachable trace metals: cadmium, chromium, copper, lead, and zinc. The trace metals were analyzed by ICP. To separate anthropogenic from geogenic input, several approaches were made, including comparison with sediment quality guidelines—ecotoxicological sense of heavy metal contamination and classification by quantitative indexes. Grain-size analysis and sediment composition of core sample show a sandy nature with neutral pH. Elemental sequence (ES) of the trace metals is in the order of Zn (19.2-109.56 ppm) > Si (66.46-101.71 ppm) > Ba (12.05-26.86 ppm) > As (8.18-17.36 ppm) > Ni (4.2-14.69 ppm) > Cr (3.02-9.62 ppm) > Pb (2.79-6.83 ppm) > Cu (2.2-5.29 ppm) > Co (0.9-2.05 ppm). Thus it is likely that the area may face a serious threat of metal pollution with the present deposition rates unless stringent pollution control norms are adopted. The Sediment Geo-accumulation Index shows that there is no Cr, Cu, Ni, Pb, Zn, or Fe pollution; however, the former index and the Pollution Load Index indicate arsenic pollution in the sediments.

Abstract:The palynomorph assemblage of lake sediments younger than 51.9 kaBP from Wulagai Gobi in Inner Mongolia was analyzed to reconstruct the vegetation and climate. From 51.9 to 30.6 kaBP, the vegetation was arid to semi-arid grassland with only slight changes. According to the palynomorphs, trees and shrubs were very rare. The large number and diversity of algae indicate the presence of a lake. Quantitative climatic conditions were reconstructed using the Best Analogues Method. The results indicate that the annual mean temperature was higher than that at present. The combination of temperature and annual precipitation suggests a change in the climate from cool dry to warm dry and then cool humid. Our results show that the annual precipitation values were mostly higher than that at present but were lower than 400 mm. It infers that the study area was already within the arid to semi-arid regions but with a stronger influence of the summer monsoon during 51.9 to 30.6 kaBP than at present. With slight differences mainly in time scale, the changing trend of the annual temperature curve is consistent with the other climatic records from Antarctica, Greenland, Hulu Cave (East China), and the Tibetan Plateau during the last glacial period. From 30.6 kaBP to present, very few palynomorphs were detected in the samples. Hence, no information about the vegetation and climate could be extracted. Combined with other studies during Late Pleistocene, we presume that the reason for the lack of pollen during this period was caused by an abrupt temperature fall after 30.6 kaBP or that the lacustrine conditions were unsuitable for pollen deposition. It was probably incurred by the oxidation on land prior to deposition. But for those samples only with algae, it might be caused by the fact that algae could finish their life history in a very short time in a seasonal lake.

Abstract:An ichnofossil assemblage is preserved in sediments of the Middle Bhuban Formation, Surma Group, of Miocene age from the Durtlang and Chanmari sections, Aizawl district, Mizoram, northeastern India. The studied sections comprise a thick, bioturbated and thinly bedded sandstone–silty shale facies. The preserved ichnofossils show high density and low diversity with the assemblage represented by feeding and resting traces, i.e., Psilonichnus upsilon Frey et al., 1984, Ophiomorpha isp., Teichichnus spiralis Mikulá?. 1990, Skolithos isp., Palaeophycus isp., and other horizontal burrows. Sedimentary structures associated with these traces are mainly cross bedding, flaser bedding and slump structures. Considering the distribution of the Psilonichnus ichnogenus across an integrated ichnological–sedimentological framework, the stratigraphic interval of the Middle Bhuban Formation, in which they occur, are interpreted to have been deposited under a shallow, marginal-marine channel complex dominated by tidal channels developed in quiet, brackish-water portions of a delta plain.

Abstract:Results of the global shale gas resources show that minable resources of global shale gas are 187 trillion cubic meters (tcm), of which China accounts for 36 tcm (about 20% of the total amount), which is mainly distributed in the Sichuan Basin, Yangtze Terrace, and Ordos Basin. From 2009 to 2012, China completed an accumulative number of 129 drilling wells related to shale gas, including 46 investigated vertical wells, 55 exploration wells and 28 evaluation wells, with 2012 production ranging from 25 million cubic meters (mcm) to 30 mcm. ChinaPetro has established two national-level shale-gas demonstration zones, one of which is the Changning-Weiyuan Demo Zone in Sichuan Province, in which 16 wells have been completed and 12 passed through fracture and extraction testing, with 2000 to 30000 cm per day for a vertical well and 10000 to 16000 cm for a horizontal well. The other demo zone is located in Zhaotong, Yuannan Province, and here 7 wells have been completed, with 2500 cm per day for a vertical well and 15000 to 36000 cm for a horizontal well. Because the former testing is naturally stable, the PetroChina Southwest Oil & Gasfield Company formally began “The Shale Gas Trial Pipeline Project of the Changning Region” in June 2013. When completed and put into production, it will become China’s first pipeline especially for shale gas. This pipeline in the Changning region will start with No. 201-H1 gas station and end at Shuanghe station, and will link with the Texi (Sichuang)-Anbian (Yunnan) pipeline. The total length of the pipeline reaches 92.8 km, with a designed pressure of 6.3 MPa and an estimated daily transportation amount of 4.5 mcm. As telecommunication fiber cable is being paved simultaneously with the pipeline, future shale-gas stations will be able to be controlled and managed digitally. Although construction of this pipeline marks the first step in China’s shale-gas exploration and exploitation, the cost issue has become a bottleneck constraining large-scale commercial exploration because of the deep burial of the shale gas and the high cost of drilling and fracturing. Therefore, there is still some way to go before profitable exploration for shale gas ensues.

Abstract:From 2010 to 2012, geologists at the Institute of Karst Geology the Chinese Academy of Geological Sciences carried out the “Chinese Geological Carbon Sink Projects Research”. They did investigation and research work according to three aspects of carbon sink: karst, soil, and mineral, and achieved important results. Through the investigation and test of karstification in the Guijiang River catchment of Guangxi Province, geologists obtained test data from more than 100 water points, and therefrom calculated the CO2 flux of unit area as 41 t/km2·a in the drainage area. Through the carbon sink investigation of Shanxi Huoquan Spring, Thunder Temple Spring and other spring areas in North China, geologists have preliminarily calculated that the CO2 flux of unit area was 5.3 t/km2·a in the North China karst area. According to the results of the annual survey, the total amount of karst carbon sink in China reaches about 60 million tons each year, accounting for more than 1/10 of the world karst carbon sink (600 million tons). At the same time, statistics show that atmospheric CO2 consumed by carbonate weathering of major rivers in China is 1260–1759×109 mol/yr, accounting for more than 1/10 of the atmospheric CO2 consumed by global rivers (12300×109 mol/yr). Thus karstification in China plays an important role in reducing CO2 content in the global atmosphere. Through this recent research on soil carbon sink, geologists also found that different land-use modes had great effect in karst carbon sink, so that carbon sink produced by karstification increases 2–8 times from rocky desertification to scrub to secondary forest. Carbon sink produced by karstification can be improved by 5.71–7.02 t/km2·a from farmland to secondary forest. Research also shows that dissolved organic carbon content in the soil in karst areas is 1/5 in acid soil. If 50 tons of sludge is added per hectare of soil, after 6 months per kilogram of soil organic carbon can increase on average 1.7 grams. Therefore they thought: a wide range of karst rocky desertification comprehensive treatments has an important effect for the improvement of the regional ecological environment, for maintenance of ecological security, and for promotion of the global CO2 emission reduction. Moreover, modifying karst soil with the sludge would not only improve the soil properties but also greatly improve soil carbon sequestration. This first major investigation of the Chinese mineral sink shows that consumption rate of atmospheric CO2 by silicate weathering in a basalt drainage area was 6×105 mol/km2·a, higher than the world average level; serpentine ultrabasic minerals and their total tailings storage CO2 can reach 13.5 trillion tons, equivalent to 2000 x Chinese CO2 release in 2005. Thus, in addition to carbonate karstification that can form a large number of geological carbon sinks, basalt and ultramafic rock mineral weathering also has huge potential for carbon sink. Preliminary estimates of the atmospheric CO2 amount consumed by silicate weathering in China is about 305–811×109 mol/year, accounting for 3.5%–9.3% of the global mineral consumption of atmospheric CO2 (8700×109 mol/yr). Thus, as geologists worldwide carry out further studies on the geological environment of CO2 emission reduction, then CO2 underground storage is conditional, and the prospects for solving this global problem are very bright.

Abstract:The International Geological Map of Asia at the scale of 1:5 000 000 (IGMA5000) compiled by the IUGS Commission for the Geological Map of the World (CGMW) Subcommission for South and East Asia in collaboration with the subcommissions for Northern Eurasia, the Middle East and Seafloor Maps is a major cooperative project under the aegis of CGMW with the support of UNESCO and IUGS. Launched in 2005 and completed in 2012, the enterprise involved more than 100 geologists from 20 Asian and European countries, namely Cambodia, China, DPR of Korea, France, India, Indonesia, Iran, Iraq, Japan, Kazakhstan, Laos, Malaysia, Mongolia, Myanmar, Pakistan, the Philippines, Republic of Korea, Russia, Thailand and Vietnam. It was also backed by the substantial efforts of the China Geological Survey and published by the Geological Publishing House (Beijing) in June 2013. The IGMA5000 is the first-of-its-kind digitally-created international geological map of Asia depicting the geology of both the continent and offshore areas. The map spans the entirety of Asia and its peripheral regions from the Alps in the west to the Mariana Trench in the east and from the Arctic Ocean in the north to the Java Trench in the south. It will provide an essential foundation for users to explore the geology of Asia from a global perspective and help with the understanding of the tectonic relationship between the Asian continent and its neighboring continents and oceans.