bluuebunny/crossref_metadata_2025_split huggingface dataset:
Improved TOC prediction method for shale reservoir of Wufeng Formation and the Lower part of Longmaxi Formation in Jiaoshiba Area, Sichuan Basin
Authors: Jia Rong , Xiaorong Luo , Yuping Li , Chao Li , Quanchao Wei , Guangchun Yu 
Published: December 2020

Abstract
The total organic carbon (TOC) content is the core index of shale gas reservoir evaluation. It is of great significance to quickly and accurately obtain a large number of TOC values for shale gas reservoir evaluation and sweet spots identification. The Lower Paleozoic shale gas reservoirs in southern China were once buried to a depth of more than 6000m, and the diagenesis was relatively complete. The application of various TOC estimation methods was not satisfactory so far. This paper takes the shale of Wufeng Formation and the Lower part of Longmaxi Formation in Jiaoshiba area of Sichuan Basin as the key research object. Based on the analysis and summary of well logging results, a method to improve the accuracy of TOC prediction is proposed. The improved ΔLogR technology with the participation of natural gamma-ray and bulk density logs has strong applicability, leading to accurate calculated TOC content, which has important guiding significance for exploration and development.
The role of exogenous oxygen in organic acid generation in deep reservoirs of petroleum-producing basins: Progress and prospects
Authors: Sun Zhenyu , Xu Jie , Chen Jian , Wang Susu , Jia Wanglu , Peng Pingan 
Published: December 2020

Abstract
The source, yield, and distribution of organic acids in oilfield waters in petroleum-producing basins have not been satisfactorily explained by previous studies that have focused on oxygen-containing functional groups in kerogen as the major source of such acids. This study reviews four possible mechanisms by which exogenous oxygen can participate in petroleum or organic acid generation. Biodegradation and mineral oxidation generate organic acids in oilfield waters, leading to an increase in the oxygen content of altered oils, which then have greater potential for producing organic acids. Hydrolytic disproportionation reaction and thermochemical sulfate reduction reactions at high temperatures lead to the in situ generation and accumulation of organic acids in deep reservoirs. The incorporation of exogenous oxygen increases the yield and expands the distribution of organic acids in reservoirs at various depths. The acids derived from exogeneous oxygen play critical roles in the development and preservation of deep reservoirs. Further research is required to determine the volumes and compositions of organic acids produced by these reactions, and to further understand the role of organic acids in the alteration of deep reservoirs under more realistic conditions.
Development characteristics and formation stages of tectonic fractures of Cretaceous Bashijiqike tight sandstone reservoir in Keshen gas field, Tarim Basin, China
Authors: Wang C L , Zhang C Z , Xiao X J , Tang Y L , Yang X J , Li H B , Mo T , Song B H , Fan K Y 
Published: December 2020

Abstract
The Cretaceous Bashijiqike formation in the Kuqa Depression of the Tarim Basin is ultra-low porosity and ultra-low permeability reservoir, where fractures have important influences on single well productivity and natural gas accumulation. According to the core CT scanning, casting thin section, laser copolymerization, imaging logging and other data, the basic development characteristics of fracture in this area are analyzed. Based on the analysis results of the core fracture cutting relationship, the carbon and oxygen isotope of the fractures filling, and the temperature measurement of the inclusions, the main stages of the regional fractures are determined. The results show that the fractures in the study area are mainly high angles, mostly filled with calcite and gypsum, and the fracture width is generally less than 0.2mm. There are three groups of structural fractures, which are EW/NE-SW and NW-SE, with the dominant orientations being NE-SW and NW-SE. The structural fracture were formed in three stages, which were the late Yanshan movement period-early Himalayan tectonic movement, the middle period of Himalayan, and the late period of Himalayan tectonic movement. The tectonic activity of the late Himalayan tectonic movement is the strongest, and the formation of fractures formed in this period were low degree of filling and effective.
Molecular and carbon isotopic characteristics of C6-14 hydrocarbons in the condensates from Kekeya oil field, Southwest Depression of the Tarim Basin, China
Authors: Wang Q , Jia W L , Yu C L , Zou Y R , Peng P A 
Published: December 2020

Abstract
The condensates are important oil resources generally reserved in deep layers and mainly composed of light hydrocarbons. In this study, 10 condensates samples were collected from the Southwest Depression of the Tarim Basin, and treated with the purge-and-trap and headspace single-drop microextraction (HS-SDME) techniques to study the chemical and carbon isotope composition of the C6-14 hydrocarbons. The relative amount of C6-14 hydrocarbons is significantly different between the samples. But there is still a good linear relationship between each two of the C6-9/C10-14, nC6-9/nC10-14 and iC6-9/iC10-14 ratios, indicating that the n-alkanes and isoalkanes (including aromatics) are approximately evaporated with the same ratio. And the relative amount of C6-14
n-alkanes in the samples is deceased as the depth increasing. The δ13C values of the C7-14 n-alkanes are in a range of -30.5‰∼-25‰, and consistent with the δ13C values of C14+
n-alkanes that have been reported earlier. The depth might have an unpredicTable effect on the δ13C value when it is over 6000 m, because the samples with the highest and lowest δ13C values all come from the layers at similar depths. This work might suggest that the purge-and-trap and HS-SDME techniques were practicable and reliable methods to study the light hydrocarbons in condensates, and the results could improve the understanding of the condensates from the study area.
Hydrocarbon resource evaluation of deep Paleogene source rock in Dongying Sag
Authors: Wang X H , Chen T , Niu Z C , Li Z , Hou X B , Zhang S C , Wang R , Zhang J 
Published: December 2020

Abstract
The exploration breakthrough of well Fengshenxie 101 once again shows the great potential of sandy conglomerate in deep northern belt of Dongying sag. Based on the oil source correlation, it is confirmed that the condensate oil in this well mainly sourced from the lower part of Es4. The resource of the source rocks are the key factors affecting the exploration of this hydrocarbon system. Based on restoration of original organic matter abundance, the hydrocarbon resources are calculated using genetic method. The total are 4.67 × 108t, indicating that the deep layers of the Dongying sag still have great exploration potential.
Deep and Ultra-deep oil/gas-source correlation methods: A review
Authors: Wu Yingqin , Wang Zhiyu , Yuan Longmiao 
Published: December 2020

Abstract
With the deepening of oil and gas exploration practice, the increasing degree of oil and gas exploration and the increasing demand for oil and gas, the target of oil and gas exploration is gradually transformed into deep and ultra-deep areas. Meanwhile, the genesis of deep and ultra-deep reservoirs has gradually become the focus of research by domestic and foreign scholars. Oil/gas source correlation is an important means to study the genetic relationship between oil and gas and source rocks. Based on the geological and geochemical data, this paper summarizes and analyzes the advantages and disadvantages of the current methods of deep and ultra-deep oil/gas source correlation, and puts forward the existing problems and future development direction of deep and ultra-deep oil/gas source correlation.
Characterization of the import of Botryococcus to the source rocks of the upper member of the Lower Ganchaigou Formation in the Yingxi area, Qaidam basin, China
Authors: Xu Li , Xing Lantian 
Published: December 2020

Abstract
Substantial quantities of Botryococcus fossils have been detected in the source rocks of the upper member of the Lower Ganchaigou Formation in the Yingxi area, Qaidam basin, China. Dicyclic terpane biomarkers, predominantly drimanes or homodrimanes with the same characteristics, also have been detected in extracts from the source rocks. These salient features confirm that Botryococcus is an important parent material for the high-quality source rocks of the upper member of the Lower Ganchaigou Formation of the western Qaidam basin. Our findings contribute to a better understanding on this source rock series and its mechanisms of hydrocarbon generation.
Organic carbon, bitumen content and maturity of Lower Cambrian source rocks in the northern margin of Tarim Basin
Authors: Yang Haijun , Yu Shuang , Zhang Haizu , Li Tengfei , Zhang Huifang , Chen Chengsheng , Fan Shan , Cheng Bin , Jia Wanglu , Liao Zewen , Tian Hui , Wang Yunpeng 
Published: December 2020

Abstract
The lower Paleozoic area in Tarim Basin is the key field of deep oil and gas exploration, and the lower Cambrian source rock is the focus of current research. However, due to the deep burial depth, there are few samples of Lower Cambrian source rocks revealed by drilling. The lower Cambrian source rocks are widely exposed in the northwest of the basin, which provides a good opportunity for the study of source rocks. In this paper, the organic geochemistry of three sections and a shallow drill sample from Aksu Area in the northwest and Kuruktag area in the northeast of the basin has been systematically analyzed. The total organic carbon (TOC), bitumen content and maturity of source rocks are studied. The organic carbon content of the lower Cambrian source rocks in the Keping area of the northwest basin ranges 1.49%-14.07%, and the content of bitumen ranges 7.73-24.53 mg / g • TOC. However, the organic carbon content of the lower Cambrian outcrop samples in the Sugetebulake section ranges from 0.93% to 7.90%, and the soluble organic matter content ranges from 0.73 to 5.89 mg / g • TOC. The TOC of Lower Cambrian source rocks in Yardang mountain area of northeast basin is low, ranging from 0.75% to 1.42%, and the content of bitumen is between 2.97-3.94 mg / g • TOC. In terms of organic matter abundance, the Cambrian source rocks developed in gentle slope facies are better than those in deep-water shelf facies. The measured reflectance (Ro%) of Shairik shallow drilling samples is between 1.0% - 1.7%, with an average of 1.45%. The Ro% of Sugatebulak samples is between 1.4%-1.75%, with an average of 1.55%, indicating that the overall maturity of the source rocks in the northwest is in the condensate wet gas stage. The measured reflectance of the Cambrian source rocks in the Yardangshan and Kuruktag sections in the northeast of the basin is between 1.5-2.5% RO, with an average of 1.75% ro. The overall maturity of the source rocks in the northeast of the basin is relatively higher, suggesting a wet gas stage.
Study on the characteristics of in-situ gas desorption from the Wufeng - Longmaxi shale in the Sichuan Basin
Authors: Zhenheng Yang , Ming Fan , Baojian Shen , Menhui Qian , Lingjie Yu , Ershe Xu 
Published: December 2020

Abstract
Upper Ordovician Wufeng Formation-Lower Silurian Longmaxi Formation shale in the Sichuan Basin and its periphery is an important horizon for shale gas exploration and development in my country. The rapid on-site desorption instrument independently developed by Sinopec Wuxi Institute of Petroleum Geology was used to test the desorption gas volume, lost gas volume, total gas content, natural gas components of desorbed gas and carbon isotope of methane in typical shale gas wells in this area. Data analysis shows that the carbon isotope value and characteristics of the first sample of methane can predict shale gas enrichment layers, and the total gas content and desorbed natural gas components can identify shale gas sweet spots; shale gas components and carbon isotope values can jointly identify shale gas Genesis type, kerogen carbon isotope characteristics and shale gas carbon isotope characteristics can be used as effective means for gas source comparison; shale gas composition characteristics can distinguish the preservation conditions of the area, which are indicative for the study of the degree of shale gas loss; The combined application of total gas content and initial dissipation index can better identify the sweet spots of shale gas, and avoid single-factor identification of sweet spots; the carbon isotope value of methane shows obvious fractionation effect with desorption time, which can predict shale gas production stage and residual gas content.
Dissolution of arkose under conditions relevant to deep reservoirs: the effect of organic acid on the porosity and pore size distribution of arkose
Authors: Zhang Chen , Li Yuanju , Chen Kefei , Zhou Shixin , Li Jing , Li Pengpeng , Sun Zexiang , Meng Bingkun , Fu Deliang 
Published: December 2020

Abstract
The organic acid is important in forming secondary pores and enhancing total porosity of the clastic rock. But there is little study to investigate the effect of organic acid on the porosity distribution of clastic rock from deep reservoirs. The changes in porosity, permeability, and porosity distribution of the dissolved medium-grained lithic arkose, from Yanchang Formation in Ordos Basin, were examined by nuclear magnetic resonance (NMR). The results show that porosity and permeability of rock increase with the time of exposure of the rock to the organic acid solution and it increases rapidly in the early period, then slightly increases to a saturation level. Besides, organic acid mainly changes the frequency and the shapes of T2 distribution in NMR analysis, and this study suggests that organic acid has more effect on rocks with larger pore throat than those with smaller pore throat.
Study on simulation of reservoir-controlling of fault-unconformity composite transport in Chengbei Fault Zone
Authors: Hong Zhang , Xianzheng Zhao , Jufeng Wang , Haitao Liu , Hongjun Li , Changyi Zhao , Xiaowei Dong , Da Lou 
Published: December 2020

Abstract
Due to the multi-phase tectonic movements in Chengbei Fault Zone, a superimposed pattern of Paleozoic buried hill and Cenozoic fault-step slope was developed on the North China platform. The fault–unconformity composite transport played a vital role in the oil and gas supply for the underlying buried hill and the distal high slope, resulting in the accumulation forming of multi-layer multi-type oil and gas. On the basis of seismic and well logging data, the characteristics of fault–unconformity composite transport in Chenghai buried hill and southern high slope were determined. And the reservoir-controlling mechanisms of fault–unconformity composite transport were revealed through oil and gas filling simulation experiments under different transport conditions. The results showed that the composite transport of fault and unconformity in buried hill zone was beneficial to the forming of large-scale reservoirs, and the dominant thick reservoirs or even negative tectonics under unconformity with abundant oil source were the main hydrocarbon accumulation area. As to the forming of reservoirs in the high slope, the key was the lithology configurations around the unconformity of “upper sand and lower mud” and “upper gravel and lower mudstone”. With the help of fault, the composite transport enables long-distance migration of oil and gas from the northern source rocks in Shahejie Formation, leading to hydrocarbon accumulation above the unconformity of Guantao Formation and even in the structural trough of southern high slope. These results revealed that fault–unconformity composite transport was helpful to hydrocarbon accumulation on a large scale, and even negative tectonics in buried hill below unconformity or structural troughs in high slope above unconformity are potential to form reservoirs. This provides a useful reference for theoretical research on reservoir forming in fault basins and a beneficial guidance for oil exploration in similar areas to a certain extent.
Primary productivity and basin redox conditions within the Mesoproterozoic Hongshuizhuang Formation from Chaoyang area, Liaoxi sag
Authors: Zhang Tao , Sun Shouliang , Li Yongfei , Zong Wenming , Sun Qiushi 
Published: December 2020

Abstract
The Mesoproterozoic Hongshuizhuang Formation in Liaoxi sag, northern China, is an important hydrocarbon source unit having good potentials to generate oil and gas. The total organic carbon (TOC) content ranges from 0.54% to 4.07% in the Chaoyang area. Trace element geochemistry was utilized to study the primary productivity and basin redox conditions during the deposition of Hongshuizhuang Formation black shales. The results suggest that primary productivity during the deposition of the Hongshuizhuang Formation was relatively high. The redox-sensitive elements results indicate that the Hongshuizhuang Formation was deposited under euxinic or anoxic bottom water conditions. The degree of environment restriction, diagenesis, reoxygenation, and the presence of free H2S can make some of the redox-sensitive elements proxies and primary productivity proxies not applicable. The high TOC content of the Hongshuizhuang Formation is contributed by high primary productivity in the surface water combined with euxinic/anoxic in the bottom water.
The role of water during gas generation
Authors: Ni Yunyan , Liao Fengrong , Chen Jianping , Zhang Dijia 
Published: December 2020

Abstract
Resources of coal-derived gas in the deep strata are found abundant in China. Recent advances in petroleum geochemistry suggest water may contribute hydrogen and oxygen to the formation of hydrocarbons and oxygenated alteration production. However, the role of water during gas generation has been in debate due to conflicting research results. In this study, a Jurassic coal sample from the Kuqa depression, Tarim Basin, China was artificially matured by nonhydrous pyrolysis and hydrous pyrolysis at isothermal (330 °C, 350 °C, 370 °C for 72h) and non-isothermal (440 °C, 470 °C and 500 °C at heating rate of 2 °C/h) temperatures. Both isothermal and non-isothermal experiments generated more methane but less C3-5 hydrocarbon gases and CO2 non-hydrocarbon gas in the nonhydrous system relative to hydrous conditions. In the isothermal experiment, the nonhydrous pyrolysis generated at most 24% more methane relative to the hydrous pyrolysis, but the hydrous pyrolysis generated 5%∼87% more C3-5 hydrocarbon gas and at most 28% more CO2 relative to the nonhydrous pyrolysis. In the non-isothermal experiment, the nonhydrous pyrolysis generated 25%∼94% more methane relative to the hydrous pyrolysis, but the hydrous pyrolysis generated at most 2.56 times more C3-5 hydrocarbon gas and 1.04 times more CO2 relative to the nonhydrous pyrolysis. In general, the compositional variation trend of hydrocarbon and non-hydrocarbon gases is similar between the isothermal and non-isothermal experiments. This indicates that contribution from the supercritical water in the non-isothermal pyrolysis is not essential. With the presence of water, the secondary cracking of C3-5 alkanes in the hydrous experiments was significantly suppressed, as shown by the relatively higher yield of C3-5 alkanes in the hydrous systems. The availability of exogenous hydrogen from water in the hydrous pyrolysis inhibits the carbon-carbon bond cross linking, thus the reaction pathway of hydrocarbon generation is dominated by the thermal cracking of carbon-carbon bonds. The significant increase in CO2 in the hydrous pyrolysis indicates water is not only the source for exogenous hydrogen but also the source for the excess oxygen accounted for the formation of CO2. The overall geochemical implication of these experimental results is that it is important to consider the role of water in the hydrocarbon generation, especially in the deep strata where both geological and geochemical conditions are complex.
Bioactive micropatterned platform to engineer myotube-like cells from stem cells
Authors: Tijore Ajay , Lee Bae Hoon , Salila Vijayalal Mohan Hari Krishna , Li King Ho Holden , Tan Lay Poh 
Published: December 2020

Abstract
Skeletal muscle has the capacity to repair and heal itself after injury. However, this self-healing ability is diminished in the event of severe injuries and myopathies. In such conditions, stem cell-based regenerative treatments can play an important part in post-injury restoration. We herein report the development of a bioactive (integrin-β
1 antibody immobilized) gold micropatterned platform to promote human mesenchymal stem cell (hMSC) differentiation into myotube-like cells. hMSCs grown on bioactive micropattern differentiated into myotube-like cells within two weeks. Furthermore, the up-regulation of myogenic markers, multi-nucleated state with continuous actin cytoskeleton and the absence of proliferation marker confirmed the formation of myotube-like cells on bioactive micropattern. The prominent expression of elongated integrin-β
1 (ITG-β
1) focal adhesions and the development of anisotropic stress fibers in those differentiated cells elucidated their importance in stem cell myogenesis. Together, these findings delineate the synergistic role of engineered cell anisotropy and ITG-β
1-mediated signaling in the development of myotube-like cells from hMSCs.
Fabrication of microvascular constructs using high resolution electrohydrodynamic inkjet printing
Authors: Zheng Fei , Derby Brian , Wong Jason 
Published: December 2020

Abstract
Fabrication of the intricate anatomy of vasculature within engineered tissue remains one of the key challenges facing the field of tissue engineering. We report the use of electrohydrodynamic (EHD) inkjet printing to create hydrogel-based microvascular tissues with hierarchical and branching channels, whose minimum feature size of 30 μm approaches the physical scale of native capillary blood vessels. The principle relies on the use of complementary thermoreversible gelling properties of Pluronic F127 (PF-127) and gelatin methacryloyl, which served as sacrificial templates and permanent matrices respectively. Human dermal fibroblasts and human umbilical vein endothelial cells were successfully co-cultured within the engineered microvascular tissue constructs for up to 21 days, and attained high cell viability. Tissue specific morphology was maintained on perfusion. The ability to create cellularised, vascularised proto-tissues with high spatial resolution using EHD inkjet printing, provides a new strategy for developing advanced vascular models with the potential to impact upon an extensive range of biomedical applications.