Driven by China’s carbon peaking and carbon neutrality goals and the low-carbon transition of offshore oil and gas operations, the integration of offshore oil and gas with wind, solar, marine, and hydrogen energy is emerging as an important pathway for balancing energy security, emission reduction, and operational efficiency. Focusing on system boundaries and positions along the energy chain, this paper classifies offshore oil and gas–renewable energy integration into four representative pathways: shore power electrification, platform microgrid integration, hydrogen production and export, and energy islands or regional hubs. This study provides a structured narrative review of the key technologies, major constraints, and feasible implementation approaches associated with these pathways from the perspectives of offshore microgrid architecture, energy storage and backup, energy management, and offshore engineering installation, operation, and maintenance. The results indicate that the coordinated use of multiple energy sources and microgrid-based integration is particularly relevant to single-platform and small-cluster scenarios requiring local power balancing and progressive electrification. However, wider deployment remains constrained by resource intermittency, the safety and lifetime of energy storage systems, cross-system coordinated control, offshore engineering reliability, and the lack of a comprehensive standards system. This study provides a reference for offshore platform electrification retrofits in China, the comparison and selection of integration schemes, and the planning of demonstration projects.

The first oil and gas well in the South Yellow Sea Basin was completed in 1961. In 1984, 2.45 tons of light oil were obtained from the Cenozoic strata. However, it remains the only large oil and gas basin in China’s offshore area without industrial oil and gas discoveries. Although the consensus is that the South Yellow Sea Basin is a foreland basin, and the oil and gas exploration prospects are promising, the research on the regional structure and the tectonic evolution of the foreland basin system is weak, which seriously hinders the process of industrial oil and gas discoveries. This paper reports the results of over 30 years of onshore and offshore investigations and well-seismic joint interpretation in the study area: for the first time, the mountains and basins formed by the collision of the North China and Yangtze plates were discovered in the geological survey of the northern islands of the South Yellow Sea Basin; the C-type eclogite chronology of Qianliyan Island, the characteristics of the foreland basins and intracontinental foreland basins around the South Yellow Sea, and the tectonic evolution characteristics and models of the basins were clarified. Through the zircon/phosphate fission track analysis of the deep black Jurassic strata in the Qianyuan S-2 well, it was revealed that the collision and subduction of the Pacific Plate against the Eurasian Plate since the Late Cretaceous–Paleogene led to large-scale uplift movements, and more than 3000 m of strata were eroded in the basin area. This is consistent with the multiple unconformities of E/N, K/N, and T2/N identified by well-seismic joint interpretation, and is also the main reason why oil and gas have been difficult to preserve in the South Yellow Sea Basin since the Middle Triassic–Jurassic. Deep prototype oil and gas exploration in the basin may be the preferred option for current oil and gas exploration deployment, which is conducive to achieving industrial oil and gas discoveries.

In this paper, we investigated the pre- and post-earthquake deformation characteristics of the Longmenshan Fault Zone using long-term ground tilt data from three monitoring stations near the fault zone before the May 12, 2008, Ms8.0 Wenchuan earthquake. The anomalous changes in the EW component are more pronounced than those in the NS component, and at certain stages, there are tilting trend reversals or abnormal tilting rates: before 2004, the annual tilt rates to the west at Maoxian, Wenchuan, and Ya’an stations were -830 ms/a, -210 ms/a, and -1060 ms/a, respectively. Between 2005 and mid-2007 these rates diminished to 25%,16% and 33% of their earlier magnitudes. From late 2007 until the earthquake, the rates were -88%, -28%, and 114%. Additionally, a short-term tilt disturbance lasting about 7 months was detected along the fault zone, propagating from southwest to northeast at approximately 104 km/year. The study concludes that the significant decrease in tilt rates near the epicenter in the 3 years before the earthquake reflects the fault’s increasing locking behavior, while the increase in tilt rate amplitude in areas farther from the epicenter in the half-year preceding the earthquake indicates a release of locking, accelerating the earthquake occurrence. Furthermore, two Ms8.0 earthquakes in Sumatra significantly influenced these short-term tilt disturbances and their propagation, potentially accelerating the strain accumulation process leading to the Wenchuan earthquake, and a stress propogation model for tilt transient disturbances was proposed. Finally, the analysis results obtained from a larger spatiotemporal scale are of great reference value for grasping the distribution laws of seismic precursors, understanding the activity behavior of the fault zone and exploring its disturbance mechanism.

Recent breakthrough exploration wells in the Huagang Formation in the Y-area of the central anticlinal zone of the Xihu Sag have confirmed the significant exploration potential of structure–lithology complex hydrocarbon reservoirs. However, limited understanding of the provenance system, sedimentary facies, and microfacies has hindered further progress in complex hydrocarbon exploration. Analysis of high-precision stratigraphic sequences and seismic facies data, mudstone core color, grain-size probability cumulative curves, core facies, well logging facies, lithic type, the heavy-mineral ZTR index, and conglomerate combinations in drilling sands reveals characteristics of the source sink system and provenance direction. The Huagang Formation in the Y-area represents an overall continental fluvial delta sedimentary system that evolved from a braided river delta front deposit into a meandering river channel large-scale river deposit. The results indicate that the primary provenance of the Huagang Formation in the Y-area of the Xihu Sag is the long-axis provenance of the Hupi Reef bulge in the northeast, with supplementary input from the short-axis provenance of the western reef bulge. Geochemical analysis of wells F1, F3, and G in the study area suggests that the prevailing sedimentary environment during the period under investigation was characterized by anoxic conditions in nearshore shallow waters. This confirms previous research indicating strong tectonic reversal in the northeast and a small thickness of the central sand body unrelated to the flank slope provenance system. The aforementioned findings deviate from conventional understanding and will serve as a valuable point of reference for future breakthroughs in exploration.

Cretaceous-Miocene sedimentary rocks of northern Borneo contain a record of sediment routing linked to subduction of the paleo-Pacific and closure of the proto-South China Sea. How the sediment routing system responded to these changes continues to be debated, hindered by limited datasets. New Sr isotope data, combined with previous geochemical and chronological data, to determine the provenance of the Cretaceous-Miocene sediments in Borneo. Late Cretaceous-early Paleocene Lubok Antu Mélange, Lupar Formation and Layar Member of the Rajang Group in Sarawak, central Borneo have low 87Sr/86Sr ratios and high ƐNd values and are dominated by Cretaceous detrital zircon grains. The results consistent with sources from the collapsed upper Mesozoic magmatic belt on the Sunda Shelf. In the Paleocene-Eocene Kapit, Pelagus, Metah and Bawang Members of the Rajang Group, there is a decrease in ƐNd values and an accompanying increase in Permian-Triassic and pre-Permian zircon ages. These trends imply that materials eroded from the Eastern Province of Malay Peninsula became progressively more important to the Sarawak region after the early Paleocene. By contrast, to the east, Eocene strata in the Sabah region remain dominated by Cretaceous detrital zircons, sourced mainly from the Schwaner Mountains. Large numbers of Permian-Triassic detrital zircon ages in the Oligocene-middle Miocene strata of Sarawak and Sabah reflect a drainage network extending to older strata along the Malay Peninsula region since the late Eocene. These sources were cut off once South China Sea began to open, leaving the Schwaner Mountains and uplifted central Borneo as the dominant source of sediments in Sabah. The observed changes in sediment provenance between Sarawak in the west and Sabah in the east reflects changes in sediment routing that tracked subduction of the paleo-Pacific plate and the progressive closure of the proto-South China Sea during the late Cretaceous to middle Miocene.

"The 21st Century Maritime Silk Road" (hereinafter referred to as the "Maritime Silk Road") is an important initiative proposed by China in response to the trend of economic globalization. The abundant clean energy resources along its route have significant implications for achieving carbon neutrality, addressing global climate change, and strengthening international cooperation. However, countries along the Maritime Silk Road have varying levels of economic and technological development, resulting in differences in the development and utilization of clean energy resources. This article provides an overview of the distribution and resource size of clean energy sources such as wind energy, tidal and current energy, and wave energy along the Maritime Silk Road, as well as the development status and potential of various countries. It discusses the importance and prospects of maritime clean energy for countries along the Maritime Silk Road. The article suggests that maritime clean energy is an important field for future energy development, with broad application prospects. In particular, countries along the Maritime Silk Road have enormous potential in the development and utilization of maritime clean energy, which is also one of the important means to optimize China's energy supply structure and mobilize the participation of countries along the Maritime Silk Road in its construction. The development and utilization of maritime clean energy require tailored approaches, the establishment of effective resource assessment methods, the development of talent and disciplinary systems, and the construction of open and inclusive platforms for international cooperation and exchange.

Through extensive data research and analysis, this paper comprehensively summarizes the status and key insights of global carbon dioxide capture and storage (CCS) development. It aims to gain a comprehensive understanding of the relevant policies, technologies, and security measures adopted by major countries in their CCS development processes. Furthermore, it explores the existing status and limitations of China’s offshore development efforts, while providing valuable recommendations for enhancing China’s offshore CCS initiatives, as well as serving as a reference for other nations worldwide. Offshore CCS plays a crucial role for China to achieve the development target of carbon peak and carbon neutrality, due to its energy structure and industrial distribution. While China possesses significant offshore CCS potential, achieving commercialization still requires substantial efforts. To facilitate the process and draw insights from successful experiences in other countries, this paper illustrates the characteristics and generalizes the experience of offshore CCS industry practices in America, Europe and Japan, respectively. Furthermore, it is recommended that a new round of investigation into offshore CCS potential be conducted, while promoting integrated collaboration between geological surveying and marine scientific research. Additionally, further research on industrial policies and green financial strategies should be undertaken.

During the Miocene, several reefs formed in the Beikang Basin, South China Sea, which may be potential targets for hydrocarbon exploration. This is due to the environment that developed as a result of the collision, splitting, and splicing of the Nansha Block, which was influenced by the Neogene expansion of the area. However, studies on the types, distribution, controlling factors, and evolution stages of these reefs are scarce. In this study, we used high-resolution seismic data and extensive well-drilling records to gain insights into the evolution of reefs in this particular area. Six distinct types of reefs, namely, the point reef, the platform-edge reef, the block reef, the bedded reef, the pinnacle reef, and the atoll reef, were identified based on our data. These reefs underwent four stages of development. During the initial stage, a few small-sized point reefs emerged in the basin and experienced significant growth during the early Middle Miocene. In the flourishing stage, the reefs predominantly thrived around the Central Uplift and Eastern Uplift areas. In the recession stage, the reefs began to deteriorate during the late Middle Miocene period as a result of the rapid increase in relative sea level caused by tectonic subsidence. In the submerged stage, since the Late Miocene, as the relative sea level continued to rise steadily over time, many reefs that had previously flourished surrounding the Central Uplift and Eastern Uplift areas became submerged underwater, with only a handful of atoll reefs surviving near islands located on the Eastern Uplift. This study indicated the presence of a significant number of well-preserved reefs in the Beikang Basin that have experienced minimal subsequent diagenesis and therefore exhibit high potential as reservoirs for oil and gas exploration.

With the melting of ice and snow in the Arctic region caused by global warming, it not only highlights the advantages of shipping lane resources in the Arctic region, but also brings opportunities for the exploration and development of rich hydrocarbon resources in the Arctic region. This will have a profound impact on the global energy supply and demand pattern and transportation structure. According to the data provided by the U.S. National Geological Survey, the Arctic region is rich in hydrocarbon reserves, with 90 billion barrels of oil reserves and 1669 billion cubic meters of natural gas reserves. Hydrocarbon reserves account for 22

The newly collected seismic data and the existing drilling data provide a good opportunity to better understand the carbonate platform distribution characteristics and the hydrocarbon resource potential in the Xisha sea area of the South China Sea. Based on the seismic data and the reflection characteristics of the carbonate platform’s edge, three boundary indicators were established: abrupt lithological interfaces, fault interfaces, and tidal channels. Combined with the regional geological settings, its spatial and temporal distribution was clearly identified for the first time. The development of the Miocene carbonate platform in the Xisha sea area is divided into six phases, which are further assigned to three evolutionary stages: the bloom stage, the recession stage, and the submerged stage. The sedimentary facies belt of the carbonate platform in each stage is well developed, and the reefs are mainly distributed on the west and southwest edges of the platform. The analysis of the data indicates that the area of the reef and carbonate platform reached 80,000 km2 during the mature period, followed by a retreat period where the scale decreased with the platform’s decline. The Miocene carbonate rocks in the Xisha sea area are widely distributed. They have experienced multiple periods of exposure and infiltration, which further improved the quality of their physical properties for hydrocarbon reservoirs. According to the regional hydrocarbon geological conditions in this area—including the source rock, migration system and the capping layer—the hydrocarbon accumulation potential is preliminarily discussed in this paper. A reservoir model of the reef and carbonate platform is established, which is proposed as typical characteristics of “lower generation, upper accumulation”. It is pointed out that the carbonate platform in the Xisha sea area adjacent to the Huaguang Sag in the Qiongdongnan Basin and the northern Zhongjiannan Basin is a potential area for oil and gas exploration.

In this study, high-resolution seismic profiles and well data provided a good opportunity for better understanding the reefs and carbonate platforms in the Wan’an Basin, southwest of the South China Sea, and also provided valuable information for the oil–gas exploration in the reef reservoirs. Four evolutional phases, including the initial phase, the prosperous phase, the recession phase and the submerged phase, of the reefs and carbonate platforms are proposed according to our data. In the Early Miocene, a few small, isolated carbonate platforms initiated in the center of the basin. In the Middle Miocene, they flourished and mainly formed around the Northern Uplift and Central Uplift, with two belts of carbonate platforms in the western area and eastern area that were mainly platform-edge reefs, massive reefs and a few point reefs. In the Late Miocene, the carbonate platforms began to retreat towards the high topographic position because of the rising of sea level. Meanwhile, the numbers and styles of reefs increased to include platform-edge reefs, massive reefs, atoll reefs and point reefs. Since the Pliocene, most of the carbonate platforms have been covered by detrital materials from terrestrial sources. Crustal tectonic activity provides favorable topography for reef growth and the distribution of platforms, and eustasy controlled the vertical growth and lateral migration of reefs. Since the Late Miocene, the rapidly crustal tectonic subsidence and the rising of relative sea level may lead to the drowning of the carbonate platform.

The southern continental margin-slope area of the South China Sea is a complex passive continental margin with diverse tectonic structures and movements. This area is rich in gas hydrate resources and is also an area with a high incidence of potential geological hazards. Identifying and understanding the potential submarine geological hazards in this area is very important for disaster prevention and management during the future exploration and development of marine resources. In this paper, five types of potentially hazardous geological bodies are identified in the research area through high-precision two-dimensional seismic processing and interpretation, including submarine mounds, pockmarks, mass transport deposits, submarine collapses and faults. At the same time, the seismic reflection characteristics and the changes in its morphology and surrounding strata are described. In addition to the causes of geological hazards in this region and their influence on exploration and development, the research prospects of geological hazards in this region are also suggested. Special tectonic and sedimentary conditions, fluid activities and hydrate decomposition may be the conditions for geological hazards in this region, which pose a significant threat to the exploration and development of seabed resources and marine engineering construction in this region. Not only does our conclusion provide useful data for the development and utilization of gas hydrate, but it also presents theoretical suggestions for reducing geological hazards in the development process.

在南海扩张过程中微板块断裂、碰撞、拼接的构造背景下,南海南部中新世以来发育碳酸盐岩台地及生物礁,经过后期成岩改造形成了大量碳酸盐岩储层并蕴藏着丰富的油气资源.为了了解该海域碳酸盐岩储层的发育特征和成因机制,以北康盆地高精度二维地震资料为基础并结合邻区岩心、薄片资料,对该区域碳酸盐岩储层发育的类型、储集空间、成岩作用以及控制因素开展了系统研究.结果表明,南海南部碳酸盐岩储层类型多且储集空间丰富,主要有两类,分别为礁滩储层和不整合面岩溶储层;发育多种孔隙类型,包括原生孔隙和次生孔隙,以次生孔隙为主,包括铸模孔、粒内溶孔、粒间溶孔和晶内溶孔等.该区域碳酸盐岩储集空间主要受白垩化作用、溶蚀作用和白云岩化的建设性改造,并且主要受构造、沉积、古气候和流体活动因素的控制.北康盆地碳酸盐岩可以作为良好的储层,并具有良好的油气成藏条件,能形成"下生上储"的碳酸盐岩油气藏.

以广州海洋地质调查局二维多道地震资料和国外钻井资料为基础,厘清区域地质演化过程及其对盆地地层发育的影响,建立邻区盆地地层层序格架.利用跨盆地地震测线,参考邻区盆地,厘定南薇西盆地地层层序及年代,分析地层生储盖组合特征及其油气地质意义.结果表明,盆地内可追踪识别出7条不整合面(T1,?T2,T3,T31,T4,T5,Tg),将地层划分为7个层序,除T1界面之外,其他不整合面分别对应新生代重要地质事件(广雅运动、万安运动、南沙运动、南海运动、西卫运动、礼乐运动);盆地成盆年代与邻区盆地相同,基底年代为晚白垩世,推测主要发育花岗岩、火成岩和变质岩,T3界面是盆地内最为显著的不整合面,年代为10.4?Ma,对应万安运动;始新世以来发育三种类型生储盖组合,中新世盆地发育碳酸盐岩地层,可为良好的储层,盆地生、储、盖组合较好,具有良好的油气资源前景.

The apparent lack of pre-seismic crustal deformation preceding the 2008 Ms8.0 Wenchuan earthquake has been the subject of debate. In this study, tiltmeter data recorded close to the earthquake epicenter were analysed using spectrum and wavelet analysis. Changes in the stress field before the earthquake were analyzed based on the Benioff creep release and changes in regional Global Navigation Satellite System (GNSS) baselines. The characteris-tics of far- and near-field seismicity and deformation processes were investigated using rock fracture experiments. The results show that during pre-seismic strain energy accumu-lation, there was a synergy between stress field changes both proximal and distal to the ep-icenter; moreover, we identified a strong correlation between Benioff creep release and shortening of the LUZH-GUAN GNSS baseline. During the sub-instability stage, the de-formation characteristics of different structural sectors differed; faults near the epicenter were in a highly locked state, and the deformation rate and wave spectra of main period waves obviously decreased. This reflects fixed point deformation driven by deep stress. These results are of great significance for understanding geophysical field observations, for clarifying pre-seismic deformation and for earthquake prediction.

The Beikang Basin is located in the southern part of the South China Sea (SCS), which is one of most tectonically complex sea areas. It is a deepwater sedimentary basin that was mainly deposited during the Cenozoic era. Owing to data restrictions, the research on carbonate platforms of this area is still in its infancy. High-resolution seismic data are analyzed to identify the Miocene carbonate platforms and reconstruct the architecture and growth history. The carbonate platforms of Beikang Basin began to develop in the Late Oligocene-Early Miocene, were extended in the Middle Miocene, and declined in the Late Miocene. The carbonate platform mainly developed during two periods: the Oligocene to the Early Miocene, and the Middle Miocene. The carbonate platforms that developed in the Middle Miocene were the most prosperous. The Middle Miocene carbonate platform in the Beikang Basin can be divided into three stages. In the first stage, the platforms had wide range which were thin. During the second stage, the platforms had a smaller range that was controlled by faults. In the third stage, the platforms were gradually submerged. The platform structure developed in the Middle Miocene at the Beikang Basin was controlled by the rate of rising/falling of the sea level and the carbonate growth rate. Based on an analysis of these changes and relationship, the platform can be divided into several patterns: retrogradation, submerged, aggradation, progradation, outward with up-stepping, outward with down-stepping, and down-stepping platforms. At the top of the carbonate platforms in the Beikang Basin a set of carbonate wings or mushrooms usually appeared. These were formed during a period of relative sea-level decline. It is believed that the Miocene carbonate platforms in the Beikang Basin are mainly controlled by tectonic and sedimentary environments, and are also affected by terrestrial detritus.

This research focuses on the seismic characteristics of various fluid flow systems at the southern margin of the South China Sea. We have considered their associated seismic responses and hydrocarbon accumulations and determined the relationships between fluid flow and hydrocarbon migration. From amplitude anomalies and geometric morphology, we identify different focused fluid flow systems, such as mud diapirs/mud volcanoes, gas chimneys, pipes, and fault-related flow systems. We observe that gas-bearing fields associated with high-amplitude anomalous, low-amplitude chaotic, and "drop-down" reflection events serve as distinguishing features of focused fluid flow systems. These systems are affected by tectonic movements and sedimentation, and they are closely related to deep, high-temperature, and high-pressure plastic fluids. Furthermore, our investigations show that focused fluid flow systems, which preferentially develop in the weak parts of the strata, as well as associated faults and fractures, often act as conduits for hydrocarbon migration and accumulation. Therefore, these systems should be given the utmost attention during seismic exploration for hydrocarbons.

The Miocene tropical carbonates deposition was extensive in the southern part of South China Sea. A large number of carbonate platforms developed on topographic highs which maybe inherited from block-tilting during the Eocene to Early Oligocene rifting phase (Fulthorpe and Schlanger, 1989, Sales et al., 1997, Eduard, 2015). The Miocene and present-day carbonate platforms both exhibit platform fragmentation and contraction, which may be controlled by syn-depositional and could lead to the submerging of whole platform ultimately (David et al., 2014). Most of the Miocene Carbonate platforms may be affected by tectonic activity and eustatic variations, and have been explained as being submerged (Vahrenkamp et al., 1998; Zampetti et al., 2004; Fournier et al., 2005; David et al., 2014). Based on the analysis of sea level rising/falling rate and carbonate growth rate, the platform could be divided into several styles (Fig.1), and growth history could be reconstructed in this article.

On the basis of interpretation of comprehensive geophysical data and foreign data analysis, there existed a lot of overburden detachment shear thrust faults along the southeastern margin of Nansha Trough, which composed imbricated overthrust nappe structure. Thrust-faulted nappe structure pattern is determined in this area, which consists of frontal fault zone, thrust fault-folded zone and root zone structures, and presents regularly zonation on plane. The detail description of the structural geometrical characteristics is given in shallow thrust fault zone, and the kinematical mechanism of thrust fault nappe structure is furtherly discussed. Overthrust nappe structure in this area is resulted from island arc-continent collision and orogenic activities.