Prefacedoi: 10.1088/1755-1315/600/1/011001pmid: N/A
Full Conference Title: The 1st Virtual Meeting on Deep Oil and Gas (VM Deep Oil&Gas 2020)Date of the Event: 30-31 July, 2020Location: Guangzhou, Guangdong, ChinaPrefaceDue to the rapid development of technology and geo-science, more and more oil and gas resources at deep areas (i.e. ∼8000m) have been discovered. However, there are still a lot of issues to be studied in such deep circumstance. This meeting aims enrolling academic and industrial scholars for the meeting. However, the CoVID-19 pandemic has influenced the academic communication, and many meetings and conferences have been canceled, postponed or changed. The Virtual Meeting on Deep Oil and Gas was finally organized in fully on-line way through internet. Regardless of the pandemic, scholars communicated their understandings on academic/technical ideas on very specific topics of deep oil and gas.Scientific topics discussed in this conference include:□ 1. Fossil fuel resources of deep basin & exploration priorities.□ 2. Geochemistry of source rocks, petroleum accumulation and alteration.□ 3. Oil and gas generation and migration in High T-P circumstance.□ 4. Geophysical and geochemical integrated exploration in deep area.□ 5. Novel geochemical technologies and basin modelling.□ 6. Geochemistry and petrophysics of unconventional oil & gas.□ 7. Deep petroleum system and modeling.□ 8. Case studies in deep and ultra-deep explorations.The VM Deep Oil&Gas 2020 was proposed in May 12, 2019 after the 10th International Conference on Petroleum Geochemistry and Exploration in the Afro-Asian Region (AAAPG2019) held in Guangzhou, China. The main reason was that some presentations in AAAPG2019 showed rapid developments of technology and theories related to deep oil and gas. This meeting aims enrolling academic and industrial scholars for discussing edge progress on evaluating potentials of deep petroleum. However, due to the CoVID-19 pandemic, many academic meetings have been canceled, postponed or changed. One month prior to the meeting, the organizing committee decided to change the meeting into an on-line one, which has been proved an effective way by some international meetings. Because the topics of the proposed meeting are firmly connected with the explorations, the organizer would not like to postpone it. Some of the presenters are from oil industry and the postponing means the delay to communicate the latest progress on deep oil exploration and discussions.
Peer review declarationdoi: 10.1088/1755-1315/600/1/011003pmid: N/A
All papers published in this volume of IOP Conference Series: Earth and Environmental Science have been peer reviewed through processes administered by the Editors. Reviews were conducted by expert referees to the professional and scientific standards expected of a proceedings journal published by IOP Publishing.• Type of peer review: Open.In the process of this volume, the conference took an open type of peer review, which means the reviewer can read the whole manuscript with full information of authors and affiliations. For guarantee the quality of review, the conference required the review make independent judgment and decision according to the manuscript quality and impression of presentation in the conference.• Conference submission management system: All manuscripts are required to be submitted to the universal e-mail address ([email protected]), which was the official e-mail address of the conference and was managed by Dr. Zhentao Li.• Number of submissions received: 60.• Number of submissions sent for review: 56.• Number of submissions accepted: 54.• Acceptance Rate (Number of Submissions Accepted / Number of Submissions Received X 100): 90%.• Average number of reviews per paper: 2• Total number of reviewers involved: 21• Any additional info on review process: In the review process, the average number of reviews per paper is two, and 21 reviewers were involved in reviewing. And most of the reviewers invited are experienced experts from both academic and industry affiliations. The acceptance rate is relatively high, however considering 38 abstracts were excluded in first-round selection for oral presentation, the acceptance rate is reasonable.• Contact person for queries:Yunpeng Wang, State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, E-mail: [email protected]
Phase characteristics of hydrocarbons generated from different types of kerogen at different maturity levels in closed systemChen, Chengsheng; Deng, Rui; Wang, Yunpeng
doi: 10.1088/1755-1315/600/1/012001pmid: N/A
For studying phase characteristics of hydrocarbons generated from different types of kerogen at different maturity levels, pyrolysis data of MM type-I and II kerogen (Maoming oil shale) and Coal type-III (Turpan coal) were collected and used for building phase models by PVT simulation technology. Then, phase diagrams, as well as physical properties (GOR, density, and viscosity) related to different kerogen types and along with maturity history, were output and carried out for comparative studies. The results show that three different types of kerogen perform different hydrocarbon generation processes, which form various yields and hydrocarbon compositions, leading to different petroleum types and diverse phase characteristics. The GORwt and the relative proportion of light and heavy hydrocarbons are two critical factors to shape the phase envelopes. The nature of kerogen with different maturity processes controls the changes of hydrocarbon compositions to form diverse phase characteristics. Their phase diagrams and physical properties on the ground conditions confirmed the different maturity ranges of black oils, light oils, and gas condensates generated by kerogen, respectively. Our study clarified that all types of kerogen at early generations (relatively low maturities) extensively generate black oils even though phase characteristics are different. In contrast, at a relatively high maturity by considering yields and expulsions of hydrocarbons, the MM type-II kerogen prefers to generate light oils, while the MM type-I kerogen prefers to generate black oils and the Coal/type-III kerogen prefers to generate gas condensates.
The main generation stage of organic acids during source-rock maturation: Implications for reservoir alteration in deep strataChen, Jian; Xu, Jie; Wang, Qiang; Wang, Susu; Sun, Zhenyu; Peng, Pingan
doi: 10.1088/1755-1315/600/1/012002pmid: N/A
Generation of short-chain organic acids during source rock maturation was simulated over 72 h, using different kerogens at 220°C–360°C. A Youganwo Formation Type I kerogen sample had the highest organic acid yield (31.0 mg g−1 total organic carbon), twice that of the Yanchang and Kezilenuer formation samples (Type II and III kerogens, ∼15 mg g−1). The organic acids were generated mainly in the oil window, regardless of kerogen type. Type I and II kerogen-bearing source rocks produced organic acids with an equivalent vitrinite reflectance (EasyRo) of 1.16%, slightly later than the peak generation of liquid hydrocarbons. Type III kerogen-bearing source rocks produced acids at an early stage (0.95% EasyRo). Most organic acids dissolved in pore waters might have been expelled with hydrocarbons from source rocks containing type I and II kerogen, migrating to reservoirs. Pores and cavities in reservoirs along faults and conduits or near source rocks could be enlarged by mineral dissolution caused by organic acids, with the generated pore space being occupied by the migrated hydrocarbons. During continued burial, these porosities would be preserved, even in deep reservoirs.
Carbonate fine lithology prediction using amplitude attribute of PS-waveQiyan, Chen; Hongqiu, Wang; Jianhu, Gao; Xin, Guo
doi: 10.1088/1755-1315/600/1/012004pmid: N/A
The Lower Permian Maokou Formation and Qixia Formation in central part of Sichuan Basin have huge natural gas exploration potential. For the Maokou Formation, there is argillaceous limestone in the limestone background, and thin dolomite reservoirs are developed. The ability to use conventional PP-wave data to predict lithology and dolomite reservoirs is insufficient. In PP-wave seismic section, the response of argillaceous limestone and dolomite in the limestone background is not obvious, which limits the prediction accuracy of lithology. Making full use of high-precision matched PP-wave and PS-wave seismic data, we find a special phenomenon in the Maokou Formation that PP-wave usually shows weak amplitude and poor continuity while PS-wave shows stronger amplitude and better continuity. Aimed at the particular phenomenon, through multi-wave seismic forward modelling, log lithology interpretation, cross plot of P-impedance with S-impedance and seismic section comparison of PP-wave and PS-wave, it is clear that the weak peak of PP-wave and strong peak of PS-wave reflects weak and subtle change in lithology, which shows the existence of argillaceous limestone in limestone background. And the gas-bearing dolomite reservoirs are characterized by low frequency and weak amplitude on PP-wave, while show weak peak feature on PS-wave. Compared with PP-wave, the favorable lithology (dolomite) distribution predicted by maximum peak amplitude of PS-wave is more consistent with reservoir distribution and origin of hydrothermal-karst-controlled dolomite. Result of lithology prediction by PS-wave is reasonable and reliable for Maokou Formation.
Recovering the phase diagram of condensate gas reservoir in Well TZ86, Central Tarim Basin using PVTsim with geochemical inputsDeng, Rui; Zhang, Haizu; Chen, Chengsheng; Wang, Yunpeng
doi: 10.1088/1755-1315/600/1/012005pmid: N/A
The phase diagram of the condensate gas reservoir in the Ordovician lithologic trap of Well TZ86 was recovered using PVTsim software with geochemical inputs (well fluid components and experiment data). The results show the error between the recovery and measured phase diagrams is within a reasonable range, indicating the reliability of the recovery result. The recovery phase diagram shows an order of CP-Pm-Tm, and the current reservoir temperature and pressure (138.49°C, 65.10MPa) confirms that the fluid belongs to the condensate gas phase currently and turns to the condensate gas-condensate oil coexistence phase when it is mined to the surface condition. The components rich in gaseous hydrocarbons caused by the gas charging in the Late Himalayan and the temperature and pressure condition determined the formation of condensate gas reservoirs in the Tazhong Uplift.
Characteristics and accumulation period of Cambrian-Ordovician hydrocarbon inclusions in Yingmai 7 area, Tabei UpliftFan, Shan; Zhang, Huifang; Lou, Hong; Shi, Chaoqun; Zhou, Siyu; Wang, Zuotao; Ma, Xiaodan; Jiang, Jun
doi: 10.1088/1755-1315/600/1/012006pmid: N/A
According to the fluorescence characteristics of hydrocarbon inclusions under the microscope, the interpenetration relationship with the occurrence veins, and the homogenization temperature, the hydrocarbon inclusions developed in the Cambrian-Ordovician reservoir in Yingmian 7 area can be divided into four periods, which correspond to four hydrocarbon accumulation events respectively. The periods of accumulation determined by the analysis of homogenization temperature and burial history are as follows: late Caledonian to early Hercyian low mature heavy oil filling, late Hercyian medium mature normal oil filling, early Himalayan high mature light oil filling and late Himalayan over mature natural gas filling. Among them, periods of I, II hydrocarbon inclusions distribution range is limited, only visible in part of the wells in Yingmai 7 area; periods of III, IV hydrocarbon inclusions in Yingmai 7 area are widely distributed, which reveals the Himalayan period of the two-stage oil and gas filling on the reservoir formation.
Exploration potential of Zhaoxian shale gas of Carboniferous Benxi Formation in Ordos BasinFu, Jinhua; Wei, Xinshan; Huang, Daojun; Zhang, Hui; Jia, Yani; Liu, Yan; Liu, Wenxiang
doi: 10.1088/1755-1315/600/1/012008pmid: N/A
In recent years, the domestic study on shale gas has been affected greatly by significant research achievements of overseas marine-facies shale gas exploration and development. In order to study exploration potential of Zhaoxian shale gas of Carboniferous Benxi Formation in Ordos Basin, the petrology, organic geochemistry and gas-bearing capacity of Zhaoxian shale samples from Benxi Formation were investigated. Based on these parameters, the exploration potential of these shales were estimated by applying mathematical statistics and analysing logging response characteristics. Results showed that the Zhaoxian shale was located in the lower part of the Benxi Formation, it was formed in a marine sedimentary environment with a thickness of 15-30m, logging was characterized by higher gamma anomalies and high compensation neutrons. The brittle minerals were mainly quartz, carbonate rock and pyrite, with an average of 36.9%, and a maximum of 50.9%. The total organic carbon (TOC) content was greater than 1% in general and the average value was 2.8%. Organic matter type of the shale samples was mainly type II2 and a few samples were of type II1 organic matter. Vitrinite reflectance values (1.82% on average) showed that shale samples were at mature-high mature stage, which enables good pyrolysis gas generation. The desorbed gas content ranged between 0.34∼2.01 m3/t with an average of 0.99 m3/t. All the evidences indicate that Zhaoxian shale from Carboniferous Benxi formation was of great potential for shale gas exploration.
Characteristics and petroleum geological significance of high-quality source rock in Gufeng Member of Middle Permian Maokou Formation in northern Sichuan Basin, ChinaFu, X D; Chen, Y N; Wang, X F; Lv, X J; Li, W Z; Yao, Q Y
doi: 10.1088/1755-1315/600/1/012009pmid: N/A
Based on the comprehensive analysis of drilling and outcrop profile data, the stratigraphic boundary between Middle Permian and Upper Permian in northern Sichuan Basin is redefined systematically. It is confirmed that the source rock of carbonaceous and siliceous mudstone is widely developed in the Gufeng Member of Middle Permian Maokou Formation in the northern part of the basin, and its thickness is mainly between 5-40 m. The source rock in the Gufeng Member has large variation scope of TOC, mainly in the range of 0.5%-30%, and the average value of most profiles more than 2.0%. It is a set of high-quality source rock as a whole. Its major organic matter is type II. At present, its thermal maturity changes greatly, and it is in the mature-over mature stage. The deep-water sedimentary environment, strong reduction conditions and high paleo-productivity jointly controlled the development and distribution of high-quality source rock in the Gufeng Member under the background of extensional structure at the end of the Middle Permian. High-quality source rock in the Gufeng Member is of great significance to the exploration of marine conventional natural gas and shale gas in northern Sichuan Basin.