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The Koktokay No. 3 pegmatite is the largest Li- Be- Nb- Ta- Cs pegmatitic rare-metal deposit of the Chinese Altai orogenic belt, and is famous for its concentric ring zonation pattern (nine internal zones). However, the formation age and evolution time span have been controversial. Here, we present the results of LA-ICP- MS zircon U- Pb dating and muscovite 40Ar- 39Ar dating. Four groups of zircon U- Pb ages (∼210 Ma, ∼193-198 Ma, ∼186-187 Ma and ∼172 Ma) for Zones II, V, VI, VII, and VIII, and a weighed mean 206Pb/ 238U age of 965 ± 11 Ma for Zone IV are identified. Also, Zones II, IV, and VI have muscovite 40Ar- 39Ar plateau ages of 179.7 ± 1.1 Ma, 182.1 ± 1.0 Ma, and 181.8 ± 1.1 Ma, respectively. Considering previous U- Pb age studies (Zones I, V, and VII), the ages of emplacement, Li mineralization peak, hydrothermal stage of the No. 3 pegmatite are in ranges of 193-198 Ma, 184-187 Ma and 172-175 Ma, with weighted mean 206Pb- 238U ages of 194.8 ± 2.3 Ma, 186.6 ± 1.3 Ma and 173.1 ± 3.9 Ma, respectively. The No. 3 pegmatite formed in the early Jurassic. The results of xenocrysts suggest that there is another pegmatite forming event of around 210 Ma in the mining district and the old zircon U- Pb ages imply that Neoproterozoic crustal rocks pertain to sources of the No. 3 pegmatite. Including the previous muscovite 40Ar- 39Ar age studies (Zones I and V), a cooling age range of 177-182 Ma is considered as the time of hydrothermal stage and end of formation. The evolution process of the No. 3 pegmatite lasted 16 Ma. Therein, the magmatic stage continued for 9-11 Myr and the magmatic-hydrothermal transition and hydrothermal stages were sustained at 5-7 Ma. These time spans are long because of huge scale, cupola shape, large formation depth, and complex internal zoning patterns and formation processes. Considering some pegmatite dikes in the Chinese Altai, there is an early Jurassic pegmatite forming event. [ABSTRACT FROM AUTHOR]

Recent studies have revealed that the Makeng Fe deposit is a skarn type deposit. However, the skarns in Makeng, occurring primarily between limestone and sandstone, are not typically associated with limestone and plutons. Different periods of intrusions, e.7. Hercynian mafic intrusions and Yanshanian (i.e. early Cretaceous) Dayang- Juzhou granitic intrusion, occurred in the Makeng deposit district. In this study, the formation processes of the skarns and Fe mineralization are constrained by detailed fieldwork, petrology, geochronology, and geochemistry. Skarns and Fe mineralization intersecting the Hercynian mafic intrusions are observed in consecutive specimens from the 106# tunnel. They suggest that the skarn formation and Fe mineralization occurred after the Hercynian mafic intrusions and are related to the later Yanshanian Dayang- Juzhou granitic intrusion. The geochronological characteristics of weakly skarn-altered diabases, the decreasing nature of Fe contents in altered diabase, and the major element compositions of pyroxenes and garnets also support that Hercynian mafic intrusions are strongly reformed by Yanshanian granitic magmas and the Fe migrated from mafic intrusion was responsible for formation of iron ore. [ABSTRACT FROM AUTHOR]

In this paper, we used a theoretical model for the variation of Eulerian porosity, which takes into account the adsorption process known to be the main mechanism of production or sequestration of gas in many reservoir of coal. This process is classically modeled using Langmuir's isotherm. After implementation in Code_Aster, a fully coupled thermo-hydro-mechanical analysis code for structures calculations, we used numerical simulations to investigate the influence of coal's hydro-mechanical properties (Biot's coefficient, bulk modulus), Langmuir's adsorption parameters, and the initial liquid pressure in rock mass during CO2 injection in coal. These simulations showed that the increase in the values of Langmuir's parameters and Biot's coefficient promotes a reduction in porosity because of the adsorption process when the gas pressure increases. Low values of bulk modulus increase the positive effect (i.e., increase) of hydro-mechanical coupling on the porosity evolution. The presence of high initial liquid pressure in the rock mass prevents the progression of injected gas pressure when CO2 dissolution in water is taken into account. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Upper Cretaceous mudstones are the most important source rocks in the Termit Basin, SE Niger. For this study, 184 mudstone samples from the Santonian-Campanian Yogou Formation and the underlying Cenomanian-Coniacian Donga Formation from eight wells were analyzed on the basis of palaeontological, petrographical and geochemical data, the latter including the results of Rock-Eval, biomarker and stable isotope analyses. Samples from the upper member of the Yogou Formation contain marine algae and ostracods together with freshwater algae (Pediastrum) and arenaceous foraminifera, indicating a shallow-marine to paralic depositional environment with fresh- to brackish waters. Terrestrial pollen and spores are common and of high diversity, suggesting proximity to land. Samples from the lower member contain marine algae and ostracods and arenaceous foraminifera but without freshwater algae, indicating shallow-marine and brackish-water settings with less freshwater influence. The wide range of gammacerane index values, gammacerane/C30 hopane (0.07-0.5) and Pr/Ph ratios (0.63-4.68) in samples from the upper member of the Yogou Formation suggest a low to moderately saline environment with oxic to anoxic conditions. In samples from the lower member, the narrower range of the gammacerane index (0.23∼0.35) and Pr/Ph ratios (0.76-1.36) probably indicate a moderately saline environment with suboxic to relatively anoxic conditions. Petrographic analyses of the Yogou Formation samples show that organic matter is dominated by terrestrial higher plant material with vitrinite, inertinite and specific liptinites (sporinite, cutinite and resinite). Extracts are characterized by a dominance of C29 steranes over C27 and C28 homologues. Results of pyrolysis and elemental analyses indicate that the organic matter is composed mainly of Type II kerogen grading to mixed Type II-III and Type III material with poor to excellent petroleum potential. Mudstones from the upper member of the Yogou Formation have higher petroleum generation potential than those from the lower member. Mudstones in the Donga Formation are dominated by Type III organic matter with poor to fair petroleum generation potential. Geochemical parameters indicate that in terms of thermal maturity the Yogou Formations has reached or surpassed the early phase of oil generation. Samples have Tmax values and 20S/(20S+20R) C29 sterane ratios greater than 435°C and 0.35, respectively. 22S/(22S+22R) ratios of C31 homohopanes range from 0.50 to 0.54. The results of this study will help to provide a better understanding of the hydrocarbon potential of Upper Cretaceous marine source rocks in the Termit Basin and also in coeval intracontinental rift basins such as the Tenere Basin (Niger), Bornu Basin (Nigeria) and Benue Trough (Nigeria). [ABSTRACT FROM AUTHOR]

The Mata Amarilla Formation dates from the early Upper Cretaceous and was deposited during a transition in tectonic regime from the extensional Rocas Verdes Basin to the Austral Foreland Basin. Detailed sedimentological logs and architectural parameters were used to define 13 facies associations. The distribution of facies associations and associated variations in fluvial architecture have enabled large-scale changes in accommodation space/sediment supply ratios (A/S ratio) to be defined for the three component sections of the Mata Amarilla Formation. The lower and upper sections are characterized by a high A/S ratio, whereas the middle section corresponds to a low A/S ratio. In the western part of the study area, small-scale variations in the A/S ratio were recognized in the middle section. The strong west to east trend in evolution of the fluvial systems coincides with the direction of propagation of the Patagonian fold and thrust belt, which is located to the west of the study area. Intervals of high A/S ratio (i.e. lower and upper sections) are interpreted to have developed during periods of increased loading by the fold and thrust belt caused by tectonic uplift. In contrast, intervals of low A/S ratio (i.e. middle section) were developed during periods of tectonic quiescence. This article suggests that the large-scale variations in A/S ratios are related to different rates of migration and growth of the Patagonian fold and thrust belt, whereas the small-scale variation occurred in response to specific periods of thrusting and folding in the Patagonian fold and thrust belt (i.e. local loads). This field example of the effects of different scales of variation in A/S ratios across the Austral Foreland Basin could be used to recognize similar tectonically forced variations in stratigraphic architecture in other foreland basins throughout the world, as well as to understand the response of fluvial systems to such changes. [ABSTRACT FROM AUTHOR]

The formation mechanism of layered ejecta craters on Mars has remained a topic of intense debate since their discovery. In this study, we perform a global morphological analysis of Martian layered ejecta craters using Thermal Emission Imaging System ( THEMIS) images and Mars Orbiter Laser Altimeter ( MOLA) data. The study focuses on the ejecta morphologies and well-defined distal rampart characteristics associated with 9945 layered ejecta craters with a diameter greater than 1.5 km distributed across the entire Martian surface. Data analysis based on the new database provides new information on the distribution and morphological details of the three major layered ejecta morphologies (single layer ejecta [ SLE], double layer ejecta [ DLE], and multiple layer ejecta [ MLE]). Global analysis is applied to the latitudinal distribution of characteristic parameters, including the ejecta mobility, lobateness values, and onset diameter. Our survey of the distribution and characteristics of layered ejecta craters reveals that strong correlations exist between ejecta mobility and latitude, and there is a latitudinal dependence of onset diameter. Our study of Martian layered ejecta craters provides more detailed information and insights of a connection between the layered ejecta morphologies and the subsurface volatiles. [ABSTRACT FROM AUTHOR]

Eclogite facies cataclasite is recognized at Yangkou in the Chinese Su-Lu ultrahigh- P metamorphic belt. The cataclasite dykes (5−15 cm wide) are bounded by mylonite/ultramylonite zones, cutting through unfoliated metagabbro and/or eclogite. The cataclasite veins (generally 2-4 cm wide) are free of mylonite boundary zones, cutting through the foliation of the high- P host rock. The dykes and veins are dominated by eclogite fragments consisting of debris of omphacite, garnet, quartz, phengite and kyanite, in a matrix of variable amounts of a schist rich in quartz, phengite and kyanite. Garnet clasts in the fragments are welded and overgrown by more Ca-rich garnet containing mineral inclusions different from those in the garnet cores. The micropoikilitic texture of garnet is typical of eclogitic pseudotachylytes. Crack-sealing K-feldspar veinlets in the cataclasite dykes also imply frictional or shock-induced melting of K-mica. The modal abundances in the cataclasite and the schist imply that the dykes formed by flow of the omphacite and garnet-dominated cataclasites into the fractures during seismic faulting, while the lower density minerals (quartz, phengite and kyanite) were largely left in the ultramylonite boundary zones. The dykes have the same composition as their host rocks, except for slightly lower Si and large ion lithophile elements and higher Mg, Ca, Cr, Co and Ni. Chromite, probably spurted from the nearby ultramafic rock, is found as rare particles in the cataclasite fragments. This indicates that material exchange occurred by mechanical mixing between the dykes and the ultramafic rock during seismic faulting. The Cr-rich eclogite minerals grown on the chromite are evidence for coseismic high- P crystallization. Short-lived crystal growth is implied by the fine grain sizes of the eclogite minerals and very limited element diffusion between the garnet clasts and their overgrowths. The fact that the host rocks are more hydrated implies that the dyke formation was not related to fluid infiltration. It appears, therefore, that stress was the key factor inducing the high- P phase transformation in the dykes. Both stress and temperature were only transiently high in the dykes, which have been metastable since they were formed. [ABSTRACT FROM AUTHOR]

Experimental data on diffusion in olivine [ABSTRACT FROM AUTHOR]

This paper presents the results of pollen and charcoal analyses carried out in the sedimentary formation of Ponta da Passadeira, south of the Tejo River estuary, Portugal. The data provide information regarding the evolution of the coastline and ecosystem of the estuary during the mid and late Holocene. The study focuses on a group of upright woody fossilized tree remains that, together with those identified earlier by García- Amorena et al. (2007), form part of the fossil forest of Ponta da Passadeira. Eight remains were identified as Pinus pinaster, four as Pinus pinea and one as Pinus sp . Two specimens of these species were dated to 6523 and 5805 cal. a BP. Pollen analysis was undertaken in a clay layer located at the same point as the fossil forest, which is currently below sea level; the base of the clay layer was dated to 4906 cal. a BP. The pollen spectra reflect the dynamics of the vegetation that grew on this deposit, whereas the sporopollinic input masks the contribution of the regional vegetation. Wood charcoal remains recovered at an adjacent Final Neolithic settlement were also analysed, and a Pinus sp. specimen was radiocarbon dated to 5050 cal. a BP. The correlation amongst the three records provides key ecological markers for the understanding of the evolution of coastline ecosystems, and helps to clarify and understand the Holocene sea rise on the Atlantic seaboard of Iberia. The geographical location of Ponta da Passadeira is strategic because it enables a more clear definition of the configuration of landscapes that show an inflection point in this area of central Portugal. [ABSTRACT FROM AUTHOR]

The beginning stages of melt segregation and the formation of leucosomes are rarely preserved in migmatites. Most arrays of leucosomes record a more advanced stage where flow dominates over segregation. However, the early stages in the formation of leucosomes and the segregation of melt are preserved in a partially melted meta-argillite from the metatexite zone (>800 °C) of the contact aureole around the Duluth Complex, Minnesota. The rock contains 2.4 modal% leucosome in a matrix consisting of 40.5% in situ neosome and 57.1% cordierite + plagioclase framework. The domainal microstructure in the matrix is a pre-anatectic feature resulting from the bulk composition. Terminal chlorite reactions produced a large volume of cordierite which, with plagioclase, formed a framework that enclosed patches of biotite + quartz + plagioclase ± K-feldspar. Upon melting, these fertile domains became patches of in situ neosome. Plagioclase in the neosome is less sodic than in the leucosome, hence segregation of melt occurred during crystallization, not melting. Segregation was delayed because the cordierite + plagioclase framework was strong enough to resist dilatation and compaction until after crystallization started. The leucosomes are small (i.e. they are microleucosomes) and display a systematic progression in morphology as length and aspect ratio increase from ~1 to 19 mm and from ~2.5 to >30 respectively. Small equant micropores form first, and in places these coalesce into small (~1 mm, aspect ratio ~2.5), isolated, blunt-ended, elliptical microleucosomes. In the next stage, micropores develop ahead of, and at ~45° to the left and right of the blunt tip of a microleucosome; one of these develops into an elliptical leucosome and an en echelon array of either a left- or right-stepping elliptical microleucosome forms. Each elliptical microleucosome in the en echelon arrays is separated by a bridge of matrix. Next, microleucosomes of greater length (>4 mm) and aspect ratio (>5) form when the bridges of cordierite + plagioclase matrix rupture and the elliptical microleucosomes link together to form a zigzag-shaped microleucosome. Finally, still longer microleucosomes with greater aspect ratios (~30) are formed by the joining of zigzag arrays. Such a progression is characteristic of the way ductile fractures grow. The segregation of melt was driven by the pressure gradient between the dilatant fracture and an adjacent in situ neosome, which drew melt to the growing fracture, thereby creating a microleucosome. The microleucosomes are filled arrays of ductile fractures. Melt was contiguous only between microleucosomes and adjacent patches of in situ neosome. The length-scale of segregation was ~5 mm, the size of a typical patch of in situ neosome, and restricted by the surrounding impermeable cordierite + plagioclase framework. The melt in the microleucosome was the most fractionated and the last to crystallize. All microleucosomes contain entrained minerals as a consequence of their mechanism of growth. Rupture of the bridges resulted in the entrainment of pre-anatectic phases. However, microleucosomes that cross patches of in situ neosome are also contaminated with peritectic phases that were transported with the melt. [ABSTRACT FROM AUTHOR]

Regionally extensive 3D seismic data from the Lower Congo Basin, offshore Angola, have been used to investigate the influence of salt-related structures on the location, geometry and evolution of Miocene deep-water depositional systems. Isochron variations and cross-sectional lap-out relationships have then been used to qualitatively reconstruct the syn-depositional morphology of salt-cored structures. Coherence and Red-green-blue-blended spectral decomposition volumes, tied to cross-sectional seismic facies, allow imaging of the main sediment transport pathways and the distribution of their component seismic facies. Major sediment transport pathways developed in an area of complex salt-related structures comprising normal faults, isolated diapirs and elongate salt walls with intervening intraslope basins. Key structural controls on the location of the main sediment transport pathways and the local interaction between lobe-channel-levee systems and individual structures were the length and height of structures, the location and geometry of segment boundaries, the growth and linkage of individual structures, and the incidence angle between structural strike and flow direction. Where the regional flow direction was at a high angle to structural strike, transport pathways passed progressively through multiple intraslope basins in a fill and spill manner. Segment boundaries and structural lows between diapirs acted as spill points, focusing sediment transport between intraslope basins. Channel-lobe transitions are commonly associated with these spill points, where flows expanded and entered depocentres. Deflection of channel-levee complexes around individual structures was mainly controlled by the length of structures and incidence angle. Where regional flow direction was at a low angle to structural strike, sediment transport pathways ran parallel to structure and were confined to individual intraslope basins for many tens of kilometres. Spill between intraslope basins was rare. The relative position of structures and their segment boundaries was fixed during the Miocene, which effectively pinned the locations where sediment spilled from one intraslope basin to the next. As a result, major sediment transport pathways were used repeatedly, giving rise to vertically stacked lobe-channel-levee complexes along the pathways. Shadow zones devoid of coarse clastics developed in areas that were either structurally isolated from the sediment transport pathways or bypassed as a result of channel diversion. [ABSTRACT FROM AUTHOR]

Understanding the relationship between sedimentation and tectonics is critical to the analysis of stratigraphic evolution in foreland basins. Previous models of foreland basins have explained stratal development, but were done generally under the assumption that steady allogenic forcing produces a steady stratigraphic response. They did not consider autogenic shoreline behaviour during the development of the subsidence pattern characteristic of foreland basins. We present a mathematical model and flume experiments that explore how subsidence and sediment-supply rates control the shoreline trajectory and the stratal patterns that fill foreland basins. Through these models, we found differing autogenic responses in the rate and direction of shoreline migration, and these generated three distinct styles of stratal architecture, despite the constant external forcing (i.e. constant sediment discharge and basin substrate tilting). The first response was 'autoretreat', where shoreline migration switched from initial progradation to retrogradation. The second response was progradation followed by constant aggradation of the shoreline. The third response was maintained progradation with a markedly accelerating rate. We termed this latter newly observed autogenic behaviour 'shoreline autoacceleration'. These three modes of shoreline behaviour and their accompanying stratal architecture provide a basic framework for the relationship between sedimentation and tectonic activity in foreland basins under the simplified conditions presented here. [ABSTRACT FROM AUTHOR]

Two incomplete bones referred to ankylosaur scapulocoracoid and humerus are described, which were discovered from the Early Cretaceous Jiufotang Formation of Dachengzi Town, Kazuo County, Liaoning Province. Ankylosaur dinosaurs have ever been found in the Lower Cretaceous Yixian, Fuxin and Sunjiawan Formations of western Liaoning. The occurrence of ankylosaurs within Jiufotang Formation improves our knowledge on the ankylosaur stratigraphic distribution. Based on the length of scapulocoracoid, the new dinosaur is estimated to exceed 6.0 meters long, representing the largest ankylosaur in western Liaoning. [ABSTRACT FROM AUTHOR]

The Wenchuan earthquake induced large amounts of debris flows and catastrophic incidents triggered by subsequent rainstorms occurred frequently in the past 6 rainy seasons, and thus resulted in serious casualties, huge economic loss and long-term impact. In this paper, post-seismic debris flows distributed in 10 Wenchuan earthquake extremely stricken counties were verified and debris flow database consisting of 609 debris flows was established based on detailed investigation organized by Land and Resources Department of Sichuan Province. Combined with database and related studies, the impact of Wenchuan earthquake on debris flows was analyzed. And then variation of formation conditions including rainfall threshold and landform condition was analyzed by contrasting pre-seismic and post-seismic debris flows. Followed are some typical viewpoints on initiation mechanism of post-seismic debris flows. In the end of this paper, characteristics of post-seismic debris flows triggered by subsequent rainstorms were comprehensively summarized, such as regional group occurrence, high frequency, high viscosity, chain effect, huge dynamics, large scale and long duration. We hope this paper will be helpful in understanding the formation mechanism, disaster characteristics and prevention countermeasures of post-seismic debris flows in Wenchuan earthquake extremely stricken areas. [ABSTRACT FROM AUTHOR]

A new large-bodied theropod dinosaur, Datanglong guangxiensis gen. et sp. nov., was recovered from the Lower Cretaceous Xinlong Formation of the Datang Basin, Guangxi. It is unique in several features including: posteriormost dorsal vertebra with teardrop-shaped pneumatic foramen confined by enlarged pcdl, acpl and the centrum; posteriormost dorsal with well-developed, horizontal prpl; posteriormost dorsal with a parapophysis projecting more laterally than the diapophysis; brevis fossa shallow with short, ridge-like medial blade; and iliac pubic peduncle with posteroventrally expanded margin. Cladistic analysis supports the idea that this new taxon Datanglong guangxiensis is a primitive member of the Carcharodontosauria in possessing two unambiguous synapomorphies: large external pneumatic foramina and internal spaces present in the lateral surface of ilium, and a peg-and-socket ischiac articulation with the ilium. The presence of the new taxon from Guangxi further confirms that Carcharodontosauria were cosmopolitan large-bodied predators during the Early-mid Cretaceous. [ABSTRACT FROM AUTHOR]

Two new genera with two new species of sawflies, Cathayxyela extensa gen. et sp. nov. and Aequixyela immensa gen. et sp. nov., from the Middle Jurassic Jiulongshan Formation of southeastern Inner Mongolia, China, are assigned to the subfamily Xyelinae (Hymenoptera, Xyelidae). Cathayxyela gen. nov. can be distinguished by the third antennal article longer than the head; mesoprescutum and mesoscutellum nearly equal in length; the forewing with Sc meeting C before the junction of 1-M and 1-Rs; a weak and narrow pterostigma; and 3-Cu at least 1.5 times longer than the 1m-cu. Aequixyela gen. nov. is characterized by the third antennal article nearly as long as the head; the forewing with Rs+M approximately equal to 2-Rs in length; 2m-cu inclined toward the wing base and nearly reaching the middle of cell 3rm; 1m-cu as long as the 2-Cu and 3-Cu; and the cell 2cua of regular hexagonal shape. [ABSTRACT FROM AUTHOR]

Funiusaurus luanchuanensis gen. et sp. nov. was described on the basis of an incomplete skull from the Upper Cretaceous Qiupa Formation of the Tantou Basin in Luanchuan County, Henan Province. It is the second representative of lizards known from Luanchuan and adds a new member to the Luanchuan Fauna. F. luanchuanensis is a small-sized lizard and systematically assigned to the Polyglyphanodontidae of the Teiioidea because of the presence of a caniniform tooth and an elongate posterior process of the postorbital. It is distinctive in that the heterodont dentition bears 19 teeth in both the upper and lower jaws, the 3rd maxillary tooth is large and caniniform, the post-caniniform teeth in maxilla and those posterior to the 3rd dentary tooth are chisel-like in lateral view, the prefrontal possesses a fossa on its lateral surface, the postorbital with an extremely elongate posterior process and the well-developed retroarticular process has a deep fossa on its dorsal surface. In phylogeny, our analysis suggests a close relationship of Funiusaurus to the large-sized Tianyusaurus from the same basin within the Tuberocephalosaurinae. The discovery of Funiusaurus is significant in confirming the status of the Tuberocephalosaurinae, which includes a group of the Asian members of the Polyglyphanodontidae only. [ABSTRACT FROM AUTHOR]

A new bird from the early Cretaceous Yixian Formation of Liaoning, China is described. This new species, Grabauornis lingyuanensis, shares several synapomorphies with the Enantiornithes. The specimen is relatively well preserved. The skeletal morphology of Grabauornis bears close resemblance to that of other Chinese members of this clade. The brachial index (the ratio between the lengths of humerus and ulna) is 0.95, which is close to the average for enantiornithine birds. It indicates that Grabauornis was a rather good flyer, and the presence of an alula in the wing further testifies to this. [ABSTRACT FROM AUTHOR]

Fossil bamboo leaves and pollen from Upper Miocene deposits of the Shengxian Formation in Tiantai and Ninghai counties, eastern Zhejiang, China represent a rare record in Asia. The distinctive pseudopetiole and parallel venation of the leaf blades and the clearly thickened annulus of the pollen aperture place them in the subfamily Bambusoideae. Morphological analysis supports the determination of these fossil leaves as belonging to the genus Bambusium and two new species are described. Bambusium latipseudopetiolus Q.J. Wang et B.N. Sun sp. nov. has a distinctly wide pseudopetiole of 0.23 cm in width and 0.40 cm in length, several vascular bundles on parallel veins, and 5-8 lateral veins on both sides of the midrib. Bambusium longipseudopetiolus Q.J. Wang et B.N. Sun sp. nov. has a distinctly long pseudopetiole of 0.60 cm in length and 0.10 cm in width, several vascular bundles on the pseudopetiole, and 6 lateral veins on both sides of the midrib. Pollen grains from the same layer provide additional evidence of bamboos. They are characterized by 32.0-51.0 μm in diameter, a round pore 3.0-4.0 μm in diameter with a broad thickened annulus 2.5-3.5 μm around, and several conspicuous secondary folds on the exine surface. The morphological analysis leads to their assignment to Graminidites bambusoides Stuchlik. These fossils are important for the study of bamboo phytogeography in China. They demonstrate that there were bamboos growing in southeastern China during the Late Miocene and that bamboos in Zhejiang begin to diversify no later than the Late Miocene. In combination with bamboo fossils from other places, it seems that bamboos had a wide distribution across southern China during the Miocene, ranging from southwestern Yun'nan to southeastern Zhejiang. [ABSTRACT FROM AUTHOR]

Yangtzeconus priscus-Archaeospira ornata, an important earliest Cambrian benthonic Assemblage of the Yangtze micromolluscan fauna, occurs mainly in the Lower Cambrian Zhongyicun and Dahai Members of the Yuhucun Formation in E Yunnan, the Tianzhushan Member (=Huangshandong Member) of the Dengying Formation in W Hubei and the Maidiping Member of the Hungchunping Formation in C Sichuan, China. About 90% of the genera of this Assemblage are unknown from the Nemakit-Daldynian and Tommotian molluscan Assemblages of the Siberian Platform, Russia. About 90% of the Siberian molluscan genera do not occur in the Zhongyicun and Dahai Members in the Meishucun section and in the corresponding beds of the Yangtze Platform, because the Tommotian molluscan Assemblage is characterizedly abundant archaeocyathids. It is clearly indicated that the Yangtze and Siberian molluscan Assemblages represent different bio- and lithofacies and ages. The age of the pre-trilobitic Yangtzeconus priscus-Archaeospira ornata Assemblage is older than that of the Nemakit-Daldynian and Tommotian molluscan Assemblages and referable to the Earliest Cambrian. Two new genera Mcnamaraconus and Zhangwentangoconus are herein proposed. [ABSTRACT FROM AUTHOR]

Quantitative studies on the extension and subsidence of the Wanan Basin were carried out based on available seismic and borehole data together with regional geological data. Using balanced cross-section and backstripping techniques, we reconstructed the stratigraphic deposition and tectonic evolution histories of the basin. The basin formed from the Eocene and was generally in an extensional/transtensional state except for the Late Miocene local compressoin. The major basin extension ocurred in the Oligocene and Early Miocene (before ∼16.3 Ma) and thereafter uniform stretch in a smaller rate. The northern and middle basin extended intensely earlier during 38.6-23.3 Ma, while the southern basin was mainly stretched during 23.3-16.3 Ma. The basin formation and development are related to alternating sinistral to dextral strike-slip motions along the Wanan Fault Zone. The dominant dynamics may be caused by the seafloor spreading of the South China Sea and the its peripheral plate interaction. The basin tectonic evolution is divided into five phases: initial rifting, main rifting, rift-drift transition, structural inversion, and thermal subsidence. [ABSTRACT FROM AUTHOR]

The Qilian orogenic belt, as an important component of the central orogenic system, can be divided into three tectonic units from north to south: the North Qilian tectonic belt, the Central Qilian tectonic belt and the South Qilian tectonic belt. The Lajishan ophiolitic mélange zone is an important part of the South Qilian tectonic belt. The study of the formation age and tectonic attributes of the different rock units in the Lajishan is of great significance for reconstructing the tectonic evolution of the south Qilian tectonics belt and the Proto‐Tethys Ocean. The Ayishan formation is an important unit of the Lajishan mélange belt, but its stratigraphic age and formation environment are still not constrained, which limits the reconstruction of the early Palaeozoic tectonic evolution of the South Qilian tectonic belt and the closure time of the Proto‐Tethys Ocean. In recent years, a set of rock assemblages consisting of andesite, rhyolite, sandstone and pebbly sandstone have been identified in the Ayishan formation exposed in the Lajishan through detailed geological mapping in the field. They are in fault contact with the underlying ophiolite mélange. Regionally, a volcano‐sedimentary succession consisting of andesite, rhyolite, volcanic breccia, and volcaniclastic sandstone nonconformably overlies the Cambrian arc‐accretionarycomplex system in the Ayishan area. These rocks were originally assigned to the Ayishan formation and attributed an Early Ordovician age (BGMRQP, 1964, 1991). Our rhyolite samples from the Ayishan formation yielded a weighted mean 206Pb/238U age of 447 Ma using zircon U‐Pb dating, which can be interpreted as the eruption age of the volcanic rocks. These volcanic rock assemblages are distributed in sandstone, pebbled sandstone and conglomerate in the form of interlayers. Therefore, the zircon U‐Pb age of the volcanic rocks can constrain the age of Ayishan formation that it should belong to the late Ordovician rather than early Ordovician. Additionally, we propose that the Ayishan rhyolites were formed in collision‐related tectonic setting based on the geochemistry of the rhyolites, which means the initial continental collision between the Central Qilian block and the Qaidam block occurred at least in the Late Ordovician. Ayishan formation are in fault contact with the Cambrian Donggoumeikuang complex in the south. The Donggoumeikuang complex represents a Cambrian introceanic subduction system that formed in response to subduction of the Proto‐Tethyan Ocean (Yan et al., 2015; Fu et al., 2018). At 450 to 420 Ma, the Proto‐Tethyan Ocean closed and the Qaidam block collided against the central Qilian tectonics belt. Voluminous 450–440 Ma I‐type and S‐type granites (Yan et al., 2015; Tung et al., 2016) that straddle the Central and South Qilian belts formed a broad Andean‐type continental margin (Yan et al., 2019), which indicates that the transition from oceanic subduction to continental subduction occurred in 450–440Ma. At 440–420 Ma, the syncollisional and postcollisional granitoids extensively developed, accompanied by high‐pressure granulite‐facies metamorphism and anatexis in the South Qilian belt and the Qaidam block (Yu et al., 2014; Yan et al., 2015; Fu et al., 2018; Li et al., 2018). [ABSTRACT FROM AUTHOR]

The Qilian orogenic belt, as an important component of the central orogenic system, can be divided into three tectonic units from north to south: the North Qilian tectonic belt, the Central Qilian tectonic belt and the South Qilian tectonic belt. The Lajishan ophiolitic mélange zone is an important part of the South Qilian tectonic belt. The study of the formation age and tectonic attributes of the different rock units in the Lajishan is of great significance for reconstructing the tectonic evolution of the south Qilian tectonics belt and the Proto‐Tethys Ocean. The Ayishan formation is an important unit of the Lajishan mélange belt, but its stratigraphic age and formation environment are still not constrained, which limits the reconstruction of the early Palaeozoic tectonic evolution of the South Qilian tectonic belt and the closure time of the Proto‐Tethys Ocean. In recent years, a set of rock assemblages consisting of andesite, rhyolite, sandstone and pebbly sandstone have been identified in the Ayishan formation exposed in the Lajishan through detailed geological mapping in the field. They are in fault contact with the underlying ophiolite mélange. Regionally, a volcano‐sedimentary succession consisting of andesite, rhyolite, volcanic breccia, and volcaniclastic sandstone nonconformably overlies the Cambrian arc‐accretionarycomplex system in the Ayishan area. These rocks were originally assigned to the Ayishan formation and attributed an Early Ordovician age (BGMRQP, 1964, 1991). Our rhyolite samples from the Ayishan formation yielded a weighted mean 206Pb/238U age of 447 Ma using zircon U‐Pb dating, which can be interpreted as the eruption age of the volcanic rocks. These volcanic rock assemblages are distributed in sandstone, pebbled sandstone and conglomerate in the form of interlayers. Therefore, the zircon U‐Pb age of the volcanic rocks can constrain the age of Ayishan formation that it should belong to the late Ordovician rather than early Ordovician. Additionally, we propose that the Ayishan rhyolites were formed in collision‐related tectonic setting based on the geochemistry of the rhyolites, which means the initial continental collision between the Central Qilian block and the Qaidam block occurred at least in the Late Ordovician. Ayishan formation are in fault contact with the Cambrian Donggoumeikuang complex in the south. The Donggoumeikuang complex represents a Cambrian introceanic subduction system that formed in response to subduction of the Proto‐Tethyan Ocean (Yan et al., 2015; Fu et al., 2018). At 450 to 420 Ma, the Proto‐Tethyan Ocean closed and the Qaidam block collided against the central Qilian tectonics belt. Voluminous 450–440 Ma I‐type and S‐type granites (Yan et al., 2015; Tung et al., 2016) that straddle the Central and South Qilian belts formed a broad Andean‐type continental margin (Yan et al., 2019), which indicates that the transition from oceanic subduction to continental subduction occurred in 450–440Ma. At 440–420 Ma, the syncollisional and postcollisional granitoids extensively developed, accompanied by high‐pressure granulite‐facies metamorphism and anatexis in the South Qilian belt and the Qaidam block (Yu et al., 2014; Yan et al., 2015; Fu et al., 2018; Li et al., 2018). [ABSTRACT FROM AUTHOR]

The article discusses a research concerning the heterogeneity of lacustrine shale gas reservoir in Yanchang Formation in Xiasiwan area in Ordos Basin, China. It offers a definition, classification, and characterization methods of heterogeneity of lacustrine shale gas reservoir. Also addressed is the development of sand-shale thin interbed series under the deep-shallow lacustrine in Mesozoic strata.

The article presents a study on the microscopic characteristics and influencing factors of tight reservoirs of Shahezi Formation in Xujiaweizi Fault Depression in China. Methods used in the study include polarizing microscope, Nuclear Magnetic Resonance, and rate-controlled mercury penetration and low temperature nitrogen adsorption. The physical property characteristics of tight glutenite reservoirs and the three aspects of tight reservoirs physical properties are addressed.

The article presents a study concerning the reservoir characteristics of tight sandstone of Shanxi Formation in Linxing area in the North of Ordos basin in China. Key reservoir characteristics include petrological characteristics, sedimentology characteristics, and physical property. Other topics include kinds of reservoir space types of tight sandstone of the formation, sedimentary environment of the area, and cementation and dissolution for the reservoir.

The article presents research related to deep exploration integration technology application in gold deposits in Paishanlou, China, with the help of three dimensional (3D) geological spatial information system. Topics discussed include principle of deep prospecting information integration technology (DPIIT), establishment of 3D geological spatial information models, and application of DPIIT in the Paishanlou gold deposit in China.

The article presents a research report conducted on the Land Subsidence with its monitoring, impact and mechanism in the coastal cities. It states that land subsidence is a geohazard which is consisted in the lower ground surface. The geohazard is a geological state which takes place because of natural and humaninduced processes occurring in the deep subsoil.

The process of solutal convection in porous media is here studied experimentally in a Hele‐Shaw cell. Motivated by the carbon sequestration process, potassium permanganate and water are used to mimic the dissolution of carbon dioxide in brine in underground geological formations. An optical method is used to accurately reconstruct the solute concentration. In this work, we examine the influence of different calibration conditions on the measurement of the solute dissolution rate and we provide indications to improve the accuracy of the technique. [ABSTRACT FROM AUTHOR]

The Cuevas del Pino estate sits in the foothills of Sierra Morena, in calcarenite stone terrain arranged in a slightly sloping strata that gives rise to various geological formations native to the area, among these are caves which resulted from quarrying that supplied Cordoba with stone during its most splendorous centuries. The architects have created a new spatial experience that manages to value the tectonic nature of the area through the use of new architectural elements. (Photo: David Vico) [ABSTRACT FROM AUTHOR]

The article focuses on the uranium-lead age of Badu Dolerite. It includes information on the presence of cluster of carlin-like gold deposits in Youjiang basin in China. It also includes information on zircon uranium-lead analysis, cathodoluminescence images of zircon grains, and sedimentary rocks of the Yanguan Formation.

The article focuses on focuses on a study related to the Cenozoic tectonic evolution of East Kunlun Orogenic Belt in China. It includes information on the impact of Apatite Fission track thermochronology. It also presents information on Eurasian plate collision at the margin of the plateau, dating of Cenozoic sandstone samples, and samples from Shangyoushashan Formation.

The article focuses on findings of a study on discovery of Molar Tooth Structures in the Kangjia Formation at Benxi, Liaoning, citing its Significance. It states stratigraphic and sedimentary research about the Neoproterozoic strata in the Benxi area, and mentions that Kangjia Formation has a conformable contact with the underlying Neoproterozoic Qiaotou Formation. It notes molar tooth structures in the micrites of Neoproterozoic Kangjia Formation.

The article focuses on findings of a study on firstly discovered cosmic spherules in carbonaceous siltstone from the Taizi Formation of the Mesoproterozoic Shennongjia Group, Central China. It states that the spherule-bearing sequence was developed at the upper Taizi Formation, and mentions that Taizi Formation is mainly composed of grey medium-fine grained sandstone.

Podiform chromitites are characteristically occurred in ophiolites (e.g., Thayer, 1964; Dickey, 1975). However, the metallogenic processes for podiform chromitites are still unclear. Early models involved fractional crystallization and crystal settling from picritic or basaltic melts in magma chambers (Dickey, 1975; Boudier and Coleman, 1981), but it was also proposed that podiform chromitites formed from partial melting and melt extraction in host mantle peridotites (Dick, 1977; Dick and Bullen, 1984). Recent studies by the majority of authors have suggested that melt-rock interaction at the Moho transition zone may have played a key role in the formation of podiform chromitites (Zhou and Robinson, 1994; Zhou et al., 1996, 2005, 2014; Robinson, 2008; Page and Barnes, 2009; Uysal et al., 2009, 2012; González-Jiménez et al., 2011, 2015). Based on the occurrence of some ultrahigh pressure minerals (e.g. diamond and coesite) in chromitites, it has been proposed recently that the formation of podiform chromitite is likely related to multiple processes inclusing mantle recycling (Yang et al., 2007; Yamamoto et al., 2013). Although geat progresses have been made towards understanding the genesis of podiform chromitites, some fundamental issues in remain unanswered. For examples, what are the major controls on the size of chromitites? And why some ophiolites contain large podiform chromitite bodies, whereas most ophiolitic massifs are essentially chromitite-barren? The Yarlung-Zangbo Ophiolite belt is one of the most famous ophiolite zone in the world. It contains fresh peridotites as well as different-sided podiform chromitites. The Luobusha ophiolite in the eastern segment of the belt hosts the largest chromite deposit in China. In the central and western segments of belt the Dazhuqu and Dongbo ophiolitic massifs contain some small-scale chromitite bodies. Such characteristics make the Yarlung-Zangbo Ophiolites an ideal subject to investigate the major controls on the metallogenesis of podiform chromitites. The Luobusha chromitites are large lens and enclosed in dunite. In contrast, the Dazhuqu and Dongbo chromitites display generally as narrow dykes or irregular seams with dunite envelopes. The closely spatial association of the chromitites and dunite envelopes, together with their textural features, support a petrogenetic model that the chromitites from the Luobusha, Dazhuqu and Dongbo massifs form from reaction of melt with host peridotite. In terms of chemical composition of chromite, there are distinctive differences between those from the Luobusha and the Dazhuqu or the Dongbo. Chromite from the Luobusha chromitites has high Cr# (71-82), whereas Chromite in the Dazhuqu chromitites show relatively low Cr# (16-63), and chromite in the Dongbo chromitites includes low Cr# (11-47) and high Cr# (70-81) types. For the Dongbo and Dazhuqu massifs, linear trends of Cr# with MgO, FeOt, Ni, Ga, V and Sc in chromite from the chromitites and dunites of are similar to those of the host peridotites, suggesting that the melt-rock reaction may provide major budget of Cr for the chromitites. The similar compositions at a given Cr# in chromite from these rocks also demonstrate that the chromitites may have been formed by in-situ crystallization of chromite under low melt/rock ratio. In contrast, the Luobusha chromitites have different trends of compositions in chromite from that of the host peridotites, implying that the formation of the chromitite bodies requires a continual replenishment of Cr-rich melts from deeper mantle. Fractionation and accumulation of chromite from a large volume of Cr-rich melt may play an important role on the formation of the Luobusha chromitites. MORB-normalized trace element patterns of chromite from the Luobusha chromitites suggest that it has been formed from Cr-rich boninitic melt at surpra-subduction zone (SSZ) setting. However, the Dongbo and Dazhuqu chromitites have formed originally from a MORB-affinity melt at a mid-ocean ridge (MOR) environment. In summary, the Luobusha chromitites crystallized from a Cr-rich melt in a dynamic conduit, where fractional crystallization and crystal settling play a key role in formation of the large chromitites. In contrast, the small-scale mineralizations of the Dongbo and Dazhuqu chromitite pods are formed from in situ produced melts. Podiform chromitites can be formed in MOR environment, whereas the higher Cr content in boninitic melt and assimilation of subducted slab materials at SSZ setting may benefit the formation of large chromite deposit. [ABSTRACT FROM AUTHOR]

The Central Asian Orogenic Belt (CAOB) is one of the largest Phanerozoic accretionary orogen. (Windley et al., 1990, 2007; Jahn et al., 2000a, b, c; Yakubchuk, 2002, 2004; Xiao et al., 2003, 2004). It is the optimal study area for revealing the accretion and reworking processes of the continental crust. The Khanka Massif is located in the most eastern part of the CAOB, and mainly crops out in the territory of Russia, with a small segment in NE China. In addition, a large number of multi-stage granitic rocks are formed in geological evolution in this area, recording amounts of information about crustal accretion and reworking processes (DePaolo et al., 1991; Rudnick, 1995; Wu et al., 2011). In view of this, this paper uses the spatial-temporal variations of trace elements and zircon Hf isotopic compositions of phanerozoic granitoids within the Khanka Massif as a case to reveal the crustal accretion and reworking processes of micro continental massifs from the orogenic belt, further to understand the formation and evolution processes and mechanisms of the global continental crust. According to the statistics of zircon U-Pb ages of granitoids in the Khanka Massif, indicate that the granitic magmatisms in the Khanka Massif have eleven peaks: 492 Ma, 460 Ma, 445Ma, 430Ma, 425Ma, 302Ma, 287Ma, 258Ma, 249 Ma, 216Ma and 213Ma, it can be divided into eight main stages: Late Cambrian, Middle-Late Ordovician, Middle Silurian, Late Carboniferous, Early Permian, Middle-Late Permian-Early Triassic, Late Triassic-Early Jurassic, Early Cretaceous. The Phanerozoic granitoids in Khanka massif are selected in this paper as a suite of granodiorite-monzogranite-syenogranite. The SiO2 contents of the Phanerozoic granitoids exceed 65%, and has high Al2O3, low Mg#, TFe2O3, Cr, Co and Ni contents. This suggests that mixture with mantle-derived magma did not occur, and it should be a typical crustal source (Lu and Xu, 2011). Combined with evident characteristics of light rare-earth elements (LREEs) and large ion lithophile elements (LILEs) enrichment, and heavy rare-earth elements (HREEs) and high field-strength elements (HFSEs) loss, we suggest that the primary magma was derived by partial melting of lower crustal material (Xu et al., 2009), and geochemical properties of the Phanerozoic granitoids essentially reflect the nature of the magmatic source region. According to the temporal variation of zircon Hf isotopic data of Phanerozoic granitioids, zircon Hf isotopic compositions of Phanerozoic granitoids have a obvious correlation with age. With the decrease of formation time of the Phanerozoic granitoids (Late Cambrian∼Middle-Late Ordovician∼Middle Silurian∼Early Permian∼Middle-Late Permian-Early Triassic∼ Late Triassic-Early Jurassic), εHf (t) values of zircons gradually increase, whereas their TDM2 ages gradually decrease (Paleoproterozoic-Neoproterozoic), suggesting that the generation of granitic magmas from the Khanka Massif could have experienced the change from the melting of the ancient crust to the juvenile crust during Paleozoic to Mesozoic. According to the sample location, it can be found that εHf (t) values of Phanerozoic granitoids have the tendency to decrease with latitude increase, showing that components of the ancient continental crust gradually increase from south to north. However, at the same latitude range, the εHf (t) values of Phanerozoic granitoids also inconsistent. Taken together, these differences reveal the horizontal and vertical heterogeneity of the lower continental crust within the Khanka Massif. According to the relative probability of two-stage model (TDM2) ages of zircon Hf isotope from Phanerozoic granitoids within the Khanka massif, it could be divided into three stages: (1)Late Paleoproterozoic (2) Mesoproterozoic (3) Neoproterozoic. It reveals that the main part of the continental crust within the Khanka Massif were formed in Late Paleoproterozoic-Neoproterozoic. The Phanerozoic granitoids in the Khanka Massif reworked from the source rocks with different ages(Paleoproterozoic-Mesoproterozoic-Neoproterozoic). [ABSTRACT FROM AUTHOR]

The article focuses on findings of a study on geochemical characteristics and geological significance of picritic rocks in Permian Tiaohu Formation from Santanghu Basin, Xinjiang of China. Topics include magmatic activity of Permian in Santanghu Basin; characteristics of picritic rocks, such as SiO2 amount of picritic rocks; and voluminous postcollisional granitoids and Armantai and Karamaili suture zone formation age.

The article focuses on findings of a study on shallow water sandy braided river reservoir architecture. Topics include significance of the reservoir analytic hierarchy process (AHP); major reservoir located at the part of Minghuazhen formation and the Guantao Formation in Neogene; and results like formation of braided sand bar, and architecture of braided river.

The article talks about geological formation such as extensional tectonics, rifting, formation of sedimentary basins, cretaceous volcanism, emplacement of dyke swarms and development of hydrocarbon pools in and around Peninsular India. It talks of seismic profiles generated by Pre-Stacking and Depth Migration (PSDM) and Pre-Stacking and Time Migration (PSTM) processing techniques having great potential in mapping the basement faults. It also mentions mapping of dyke swarms and integration.

The article focuses on a study based on source rock and cap rock on the Upper Ordovician Wufeng Formation-Lower Silurian Longmaxi Formation as a means of shale gas reservoir assessment. Topics discussed include organic matter beneficial to the development of organic-matter pores in the Wufeng F ormation-Longmaxi Formation; indirect cap rock referring to the gypsum rock and mudstone of the Lower-Middle Triassic; and shale gas preservation conditions.

The article focuses on a study based on Characteristics and Distribution Pattern of Seafloor Sinuous Pockmark Train in the Niger Delta Basin, West Africa. Topics discussed include pockmarks as manifestations of fluids escape through the seabed; cross-sectional view of pockmark which include Vshaped morphology with a few U-shaped occurrences; pockmarks as reflection of Reservoirs' morphology and geometry; and importance of pockmarks for development of submarine channels.

The article presents a study on Botryoidal structures from the Sinian Dengying formation and Sichuan Basin in China. It highlights the characterization of its interior structural attributes and occurrences as well as its formation mechanisms. It also outlines its insertion between karst caves, dissolution fissures and bedrocks.

The article reports on uranium-lead (U-Pb) geochronology of detrital zircon and the provenance of Sanya formation at the Yinggehai Basin in South China Sea. It highlights the acquisition of zircons from heavy liquids through a Frantz magnetic separator as well as fastened in epoxy. An overview of its morphology is also presented.

The article reports on the meganodular limestone in South China. It highlights time-specific facies-based three-dimensional network structure of the Upper Ordovician Pagoda Formation in the country. It also outlines the basis of the analysis on the formation which involves the use of geochemical, paleontological and sedimentological information.

The article discusses a research concerning sandstone control factors of oil of the Third Member of Shahejie Formation in Dawangzhuang in Raoyang Sag, China. Topics include the impact of the physical properties of the third member of Shahejie Formation on hydrocarbon, the factors of oil-bearing, and reservoir quality. Methods used in the study include mercury experiments, porosity and permeability analysis, and drawing cross-plot.

The article discusses a research concerning source rocks and the accumulation contribution in residual basin, focusing on the pre-Jurassic period in the Tainan Depression in Turpan-Hami Basin, China. Topics include the formation of residual basin, tectonic development features and evolution history of Pre-Jurassic Residual Basin, and oil-source correlation and genetic method. Methods used include hydrocarbon accumulation model, core samples, and rock samples analysis.

The article discusses a research concerning geochemistry and petrography of clastic deposits from the Late Paleozoic Shihezi Formation in Eastern Ordos Basin in China, along with the implications for provenance and tectonic setting. Topics include the significance of provenance studies in reconstructing paleo-drainage systems, mineralogy and petrology of sandstones, and major, trace, and rare earth element compositions of sandstones from the formation.

The article presents a research concerning the characteristics of micro pore-throat of tight oil reservoir in Permian Lucaogou formation in Jimsar Sag in China. It offers an analysis of the reservoir properties, reservoir space, and micro pore-throat structure using poroperm testing, thin section identification, electron microscopy analysis, and other analysis. The correlation between throat parameters and porosity of micritic dolomite reservoir is discussed.

The article discusses a research concerning estimation algorithms of the methane sorption capacity of the Longmaxi Marine Shale in South China. Details about the variation of methane sorption capacity, change in the Langmuir pressure, and linear relationship between isosteric heat and standard entropy of adsorption. Also provided is information on the role of shale as the source and reservoir for natural gas.