Quantitative evaluation and models of hydrocarbon accumulation controlled by faults in the Pearl River Mouth Basin

The Pearl River Mouth Basin is the largest petroliferous basin in the northern South China Sea, where hydrocarbon accumulation is strongly controlled by fault activities. This study performed the quantitative evaluation of the effects of faults on hydrocarbon migration and accumulation in the basin. The results indicate that the critical values of vertical migration of middle-shallow hydrocarbon, including the active strength of faults and the ratio of fault throw to shale caprock thickness, were up to 10 m/Ma and 5, respectively. The lateral hydrocarbon migration efficiency of the unbreached relay zone was higher than that of the barely breached and strongly breached types. The lower critical value of shale gouge ratio for the clay sealing efficiency was 0.32. Additionally, the zones with the EW-trending transtensional faults were found to have unique dual functions of migration and stress sealing, suggesting that the linking fault positions play important roles in the lateral migration of hydrocarbons. Finally, seven hydrocarbon accumulation models controlled by faults in different tectonic settings were constructed to clarify the effects of faults on the vertical and lateral migrations of hydrocarbon. These models suggested that fine hydrocarbon exploration should be undertaken in the northeastern Baiyun Sag, and that middle-deep hydrocarbon exploration should be enhanced in the Enping, Huizhou, and southwestern Baiyun Sags.Cited as: Peng, G., Wu, Z., Dai, Y., Zhang, L., Yu, S., Wang, W., Pang, H. Quantitative evaluation and models of hydrocarbon accumulation controlled by faults in the Pearl River Mouth Basin. Advances in Geo-Energy Research, 2023, 8(2): 89-99. https://doi.org/10.46690/ager.2023.05.0

Enhancing LGMD-based model for collision prediction via binocular structure

IntroductionLobular giant motion detector (LGMD) neurons, renowned for their distinctive response to looming stimuli, inspire the development of visual neural network models for collision prediction. However, the existing LGMD-based models could not yet incorporate the invaluable feature of depth distance and still suffer from the following two primary drawbacks. Firstly, they struggle to effectively distinguish the three fundamental motion patterns of approaching, receding, and translating, in contrast to the natural abilities of LGMD neurons. Secondly, due to their reliance on a general determination process employing an activation function and fixed threshold for output, these models exhibit dramatic fluctuations in prediction effectiveness across different scenarios.MethodsTo address these issues, we propose a novel LGMD-based model with a binocular structure (Bi-LGMD). The depth distance of the moving object is extracted by calculating the binocular disparity facilitating a clear differentiation of the motion patterns, after obtaining the moving object's contour through the basic components of the LGMD network. In addition, we introduce a self-adaptive warning depth-distance, enhancing the model's robustness in various motion scenarios.ResultsThe effectiveness of the proposed model is verified using computer-simulated and real-world videos.DiscussionFurthermore, the experimental results demonstrate that the proposed model is robust to contrast and noise

我が国における研究学園都市研究の概観

二十一世紀末以降,高等教育システム改革の実施と進学者定員枠の拡大に伴い,我が国においては研究学園都市(中国語では「大学城」と称す)の設置ブームが巻き起こった。これを受けて,研究学園都市という新しい区域形態に対する多角的な研究が次第に国内の学界で注目され始めた。本論では,近年のわが国における研究学園都市研究に関する大量の文献に対し,詳細な振り返りと概観をした。そして最後に,研究学園都市に対するさらなる研究を行う意義と今後の展望をまとめた。Since the end of the twentieth century, with the reform of higher education and expansion of college enrollment, a great many university towns have been built in our country. Many scholars have paid more and more attention to research of the university town, the new form of regional pattern, from many different views. This paper has reviewed in details most of the research of university towns of our country and given some comment on this. Finally, the paper put forward the significance of further studying the university towns

Comment on "Geochronology and geochemistry of submarine volcanic rocks in the Yamansu iron deposit, Eastern Tianshan Mountains, NW China: Constraints on the metallogenesis" by Tong Hou, Zhaochong Zhang, M. Santosh, John Encarnacion, Jiang Zhu, Wenjuan Luo [Ore Geology Review, 56(2014):487-502]

International audienceIn a recent paper, Hou et al., (2014) presented their study on the Yamansu iron deposit in eastern Tianshan Mountains, NW China. Hou et al., (2014) proposed a genetic model for the iron mineralization in Yamansu, which was based on geochronology and geochemistry study on volcanic rocks and skarns. In their paper, they gave an excellent discussion on the geochemistry data of basalt. However, we would like to address the following arguments: (1) What are meanings of zircon U-Pb ages derived from the basalt and skarn? (2) Did the Yamansu basalts provide the source of iron for the skarn mineralization? 2 What are meanings of zircon U-Pb ages derived from the basalt and skarn? Hou et al., (2014) separated zircons from basalt and garnet skarn, and then dated by LA-ICP-MS. These zircons yielded coeval ages of 324.4 ± 0.94 and 323.47 ± 0.95 Ma for the basalt and skarn, respectively. These ages lead them to make the conclusion that the skarn formation in Yamansu deposit is related to subaqueous volcanism. Here, we may ask what the relations between the basalt and the skarn are. In addition, we need to know what the protolith of these skarn is, and what triggered the skarnization. If observations in the field proof the skarn were obviously later than the basalt, Hou's conclusion seems untenable

A springboard into politics: Do Chinese entrepreneurs benefit from joining the government-controlled business associations?

Business associations in authoritarian regimes behave systematically different from their counterparts in democratic regimes. Using a unique dataset of Chinese private firms, this paper examines the impacts of joining the most prominent business association in China, the All-China Federation of Industry and Commerce (ACFIC) which was initiated and strongly controlled by the government We find that ACFIC members have much higher chances to obtain formal political identities, that is, the deputy of People's Congress (PC) or the People's Political Consultative Conference (PPCC). However, ACFIC membership itself cannot help entrepreneurs acquire scarce resources that are controlled by the government. Rather, ACFIC members bear heavier tax burdens and make more informal payments to government officials. These findings suggest that the ACFIC act as a springboard into politics, rather than an effective collective action committee that can bring common benefits to its members or protect members from government predation

Experimental and Numerical Simulation of the Formation of Cold Seep Carbonates in Marine Sediments

Cold seep emissions of low temperature fluid from the marine sediment basins are mainly comprised of methane and other hydrocarbons. A series of biogeochemical processes related to methane lead to the formation of authigenic carbonate minerals. In this study, a self-built experimental device was used to study the formation process of carbonate minerals under cold seep conditions. The concentrations of pore water chemicals, HCO3− and Ca2+ at different heights of the reactor under flow conditions can be observed. According to the experimental results, the formation process of carbonate minerals under cold seep conditions was estimated, that 1 m carbonate growth needs 12,000 and 7000 years, respectively, under fast (5 mL·min−1) and slow emission (1 mL·min−1) conditions. Furthermore, TOUGHREACT was used to simulate the diagenesis process. A 1D unsteady react-transport model was developed, and the experimental data was used to constrain the simulation. The results of simulation show that the carbonates need 17,000 and 9700 years to grow 1 m under the condition of fast and slow flow scenarios, respectively. The results of this work will contribute to the study of foundation on the formation of authigenic minerals in cold seep areas, and for the physical properties of sedimentary media as well

Comprehensive Analysis of Tumor-Infiltrating Immune Cells and Relevant Therapeutic Strategy in Esophageal Cancer

A growing body of evidence has indicated that behaviors of cancers are defined by not only intrinsic activities of tumor cells but also tumor-infiltrating immune cells (TIICs) in the tumor microenvironment. However, it still lacks a well-structured and comprehensive analysis of TIICs and its therapeutic value in esophageal cancer (EC). The proportions of 22 TIICs were evaluated between 150 normal tissues and 141 tumor tissues of EC by the CIBERSORT algorithm. Besides, correlation analyses between proportions of TIICs and clinicopathological characters, including age, gender, histologic grade, tumor location, histologic type, LRP1B mutation, TP53 mutation, tumor stage, lymph node stage, and TNM stage, were conducted. We constructed a risk score model to improve prognostic capacity with 5 TIICs by least absolute shrinkage and selection operator (lasso) regression analysis. The risk score=−1.86∗plasma+2.56∗T cell follicular helper−1.37∗monocytes−3.64∗activated dendritic cells−2.24∗resting mast cells (immune cells in the risk model mean the proportions of immune cell infiltration in EC). Patients in the high-risk group had significantly worse overall survival than these in the low-risk group (HR: 2.146, 95% CI: 1.243-3.705, p=0.0061). Finally, we identified Semustine and Sirolimus as two candidate compounds for the treatment of EC based on CMap analysis. In conclusion, the proportions of TIICs may be important to the progression, prognosis, and treatment of EC

The influence of coupling mode of methane leakage and debris input on anaerobic oxidation of methane

Anaerobic oxidation of methane (AOM) is an important biogeochemical process, which has important scientific significance for global climate change and atmospheric evolution. This research examined the delta S-34, terrigenous clastic indices of TiO2 and Al2O3, and times for formation of the Ba front at site SH1, site SH3 and site 973-4 in the South China Sea. Three different coupling mechanisms of deposition rate and methane flux were discovered. The different coupling mechanisms had different effects on the role of AOM. At site 973-4, a high deposition rate caused a rapid vertical downward migration of the sulphate-methane transition zone (SMTZ), and the higher input resulted in mineral dissolution. At site SH3, the deposition rate and methane flux were basically in balance, so the SMTZ and paleo-SMTZ were the most stable of any site, and these were in a slow process of migration. At site SH1, the methane flux dominated the coupled mode, so the movement of the SMTZ at site SH1 was consistent with the general understanding. Understanding the factors influencing the SMTZ is important for understanding the early diagenesis process

Effect of lithological rhythm on gas production performance via depressurization through a vertical well in a confined hydrate reservoir

The lithological characteristics of subsurface formations control the variations in the permeability. Herein, the effect of lithological rhythm on gas production was numerically investigated for depressurization applied in a confined hydrate reservoir. The lithological rhythm structures from simple uniform, positive, and reverse rhythms to complex composite rhythms were designed. The water-to-gas ratio showed that economic feasibility of all rhythms varied with the expansion of the hydrate dissociation region. The depth of high permeability region affected the hydrate dissociation and temperature recovery. Therefore, the gas production rate of positive rhythm was higher than that of the uniform and reverse rhythms, while the reverse rhythm was economically more suitable in the later stages of the production. Furthermore, the gas and water production rates decreased with the increase in the permeability contrast. The number of composite rhythmic layers negligibly affected the gas production rate, while it significantly affected the hydrate saturation distribution, indicating an increasing hydraulic connectivity in the lateral direction that may lead to water breakthrough. Moreover, the rhythmic structures significantly affected the gas production rate and the economic feasibility, and controlled the developed depth of high hydraulic connectivity. Therefore, minor and large seepage pathways could form in a complex rhythm reservoir