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Fault step zones are well developed in faulted lake basins in the eastern part of China, among which, forward fault step zones account for a large proportion, and their spatiotemporal configuration relationship, oil and gas accumulation periods and accumulation conditions, which play a key role in the geological evaluation of regional oil and gas exploration, are difficult to study. In order to further clarify its hydrocarbon accumulation mode and filling period, the authors, by taking the Paleogene Dongying and Shahejie formations in the study area as the main target layers, and selecting wells Qidong 3-1, Zhang 10 and Chenghai 16 to represent the low, medium and high fault levels of the fault area, respectively, conducted in-depth research on the oil and gas properties and distribution laws of different charging stages in various districts of Chengbei through reservoir microlithography observation, fluid inclusion identification, salt water inclusion homogenization temperature and salinity test, GOI statistical analysis and other technologies; applied laser Raman test to effectively identify the gas composition of single inclusions in wells Zhang-10 and Qidong 3-1, determined the specific oil and gas accumulation time in Chengbei fault step zone in combination with the single well burial history, paleogeothermal history and autoclastic illite K-Ar isotopic dating technology of well Qidong 3-1, and summarized the four accumulation elements of source rocks, reservoirs, preservation and transportation in Chengbei area. There are two charging stages in the reservoir, the specific accumulation time of the first stage is from the end of Dongying to the early stage of Guantao, about 16 Ma ±, while that of the second stage is in the early stage of Minghua Town, starting from 6 Ma ± and continuing to the present. Multiple sets of reservoir layers are developed in the study area, and the special fault step structure plays a controlling role in channeling the source rocks and reservoirs, the sealing and preservation of oil and gas, and the transportation and accumulation of reservoirs. The regional accumulation conditions are relatively mature, and the lateral migration-accumulation mode of dual-source hydrocarbon supply and multi-stage accumulation and the longitudinal migration-accumulation mode of fault-sand coupling and relay climbing are reflected in the process of oil and gas accumulation.

The quality of source and reservoir rocks as well as their spatial assemblage types are crucial factors that controlling the charging, accumulation, and enrichment of tight oil resource. However, there are still deficiencies in the understanding about these factors, especially regarding differences in the mechanism of charging, accumulation, and enrichment of tight oil between different source-reservoir assemblage types, which restricts the formation of theory as well as the process of exploration and development. Taking the Qingxi Sag of the Jiuquan Basin as an example, we have drawn conclusions by field observations, core descriptions, and drilling analyses that there may be eight types of source-reservoir assemblages. Among these, there are three basic types, namely, the lower-generating and upper-reserving type, upper-generating and lower-reserving type, and sandwich-like type. In addition, there are two special types, the self-generating and self-reserving type and source-reservoir interbedding type. Moreover, the other three types are composite types, which are the lowergenerating and upper-reserving type Ⅱ, upper-generating and lower-reserving type Ⅱ, and sandwich-like type Ⅱ. Among the above mentioned eight types, the first five types are common. The results of statistical drilling and nuclear magnetic resonance experiments mutually verify the corresponding relation between source-reservoir assemblage type and tight oil enrichment. The assemblage types can be ranked according to their positive correlation with enrichment in the following order, from the highest to the lowest: self-generating and self-reservoiring type, sandwich-like type, upper-generating and lower-reservoiring type, lower-generating and upper-reservoiring type, and source-reservoir interbedding type. Differences in the mechanism of charging, accumulation, and enrichment of tight oil among the five common source-reservoir assemblage types are revealed and explained. In addition, their accumulation and enrichment patterns are determined and principal controlling factors are proposed, namely, accumulation dynamics, charging patterns, and storage conditions, which are in fact closely related to the source-reservoir assemblage types.

The dynamic physical simulation of natural gas accumulation process is one of the important means to reveal the mechanism of natural gas migration and accumulation and to summarize its distribution law. However, due to the characteristics of natural gas itself including "easy to leak, difficult to move and difficult to observe" have become holdbacks for the physical simulation of natural gas migration and accumulation. In order to reveal the migration and accumulation mechanisms of fault-controlled gas reservoirs, and to summarize the formation sequence and distribution pattern of gas reservoirs, typical reservoirs in Dongping, Mahai and Nanbaxian areas in the northwestern part of Tarim Basin were taken as examples to establish a geological evolution model for each reservoir. Aiming at the problems of gas reservoir simulation, an adjustable simulation device for gas migration and accumulation was designed, which could realize the dynamic process of structural change and clarify the phenomenon of gas charging and migration, and the formation process of typical gas reservoirs such as Dongping, and Mahai-Nanbaxian, etc. was successfully simulated. It is clear that the fault not only acts as a channel for gas migration and power transmission, but also controls the evolution sequence and distribution pattern. The formation and evolution sequence models of two different types of natural gas reservoirs, named "late accumulation" and "long-term accumulation", were proposed, the mechanism of natural gas migration and accumulation driven by "fault transmission and high pressure" was revealed, and the vertical preservation sequence featured by "co-existence of natural gas in both deep and shallow formations, and the deeper formations are more favorable for preservation" was concluded. A new concept of natural gas exploration was put forward that "if there are shallow gas reservoirs, there must be deep ones", and we can find natural gas from shallow to deep formations.

On the basis of formulating and perfecting the definition and connotation of tight oil, a comparative study was carried out on the basin formation, hydrocarbon generation, hydrocarbon preservation and reservoir formation for 9 tight oil basins of China and 6 of USA. It was concluded that China′s tight oil has great potential, but the accumulation conditions are complex and diverse. There are 9 tight oil basins in China located in 3 tectonic areas in the eastern, middle and western parts of mainland China. Due to the combined action of the 3 plates of the Pacific, Siberia and India, the type, scale and formation of tight oil basins as well as the generation, preservation and enrichment of hydrocarbon are varied and have regular change trends among the three tectonic areas. From the western tectonic area to the central and then to the eastern one, the distribution scale of tight oil changes from small to large and then to middle, and the number of tight oil distribution horizon decreases from the Upper Permian to the Middle Jurassic and finally to the Lower Cretaceous. The generation conditions of tight oil changed from bad to good and to relatively good. The types of tight oil reservoirs change from multiple and complex to relatively complex and then to relatively simple. The reservoir performance of tight oil reservoirs changes from relatively good to relatively poor and to relatively good, while permeability changes from relatively high to relatively low and to relatively high. The conditions of tight oil migration and accumulation change from relatively poor to good and to relatively good, and the types of tight oil reservoirs change from more to less and back to more. The exploration and development potential of tight oil is the largest in the western tectonic area, followed by the central and then the eastern one. The tight oil basins and tight oil accumulations in China and USA have both commonalities and obvious differences. The fundamental reasons for the differences are the stability of structures and the heterogeneity of sedimentary facies. The tight oil basins in China have poorer tectonic stability and continental deposition, while the tight oil basins in USA have better structural stability and marine deposition. As a result, the hydrocarbon generation capacity of tight oil basins in China is worse than that in USA, but the reservoir conditions are generally better than those in USA. The accumulation mechanism and model of tight oil enrichment in China are more complex than those in USA. The quality of tight oil in USA is generally better than that in China. The size of tight oil basins in USA and the exploration and development potential of tight oil are greater than those in China.

People-to-people exchange has become a heated topic of the Chinese foreign policy. Since the beginning of the twenty-first century, China has established people-to-people dialogues with the United States, the European Union, the United Kingdom, France and Russia. In 2012, China and the EU established a high-level dialogue for people-to-people exchange, making people-to-people exchange the third pillar of China-EU relations. However, China is not a newcomer to people-to-people exchanges with Europe. Why does China launch the people-to-people diplomacy? Is it a plus or a must for China as well as for China-EU relations? The author reviews the history and current situation of China's people-to-people exchange and investigates China’s motivations behind the policy. Using the historical institutionalism as an approach, this paper argues that people-to-people diplomacy is a key component of the contemporary Chinese foreign policy towards Europe. China has long been an unequal counterpart to Europe since the 1840s. After the development of bilateral political and economic cooperation in the past four decades, people-to-people diplomacy is the last part that China needs to finish in order to regain equal status with Europe. In addition, it is also a step towards realising the "great rejuvenation of the Chinese nation".

The purpose of 3D human pose estimation is to predict information such as the 3D coordinate position and angle of human joint points, and construct human representations (such as human bones) for further analysis of human posture. With the continuous advancement of deep learning methods, more and more high-performance 3D human pose estimation methods based on deep learning have been proposed. However, due to the human occlusion of the picture and the large demand for training scale, there are still challenges in 3D human pose estimation. The research purpose of this paper is to review a number of research papers in recent years, analyze and compare the reasoning process and core elements of these methods, and comprehensively elaborate the 3D human pose estimation methods based on deep learning in recent years. In addition, this paper also introduces the relevant datasets and evaluation indicators, compares the experimental data of some models on the Human3.6M dataset, Campus dataset and Shelf dataset, and analyzes and compares the experimental results. Finally, according to the results of this survey, the difficulties and challenges faced by the current 3D human pose estimation are discussed, and the future development of 3D human pose estimation is discussed. [ABSTRACT FROM AUTHOR]