Fine-grained sediments contain over 90% of marine methane hydrate, significantly impacting the global carbon cycle and climate system. The formation of hydrates in these sediments is complex and not well understood. Minerals play a crucial role in determining the properties of porous media (sediments). We investigated nucleation controls using quartz-bentonite mixed samples based on data from the South China Sea. Differential scanning calorimetry (DSC) shows a nonlinear nucleation efficiency pattern. Low-field nuclear magnetic resonance and particle size analysis reveal a three-stage mechanism: (1) initial inhibition due to strong water absorption by minor clay; (2) promotion through optimal clay aggregation into ”pseudo-coarse particles” that enhance pore space; (3) inhibition caused by pore filling from excessive clay. These findings clarify the unique nonlinear accumulation patterns of hydrates in fine-grained sediments, providing essential insights for assessing global methane inventories and their potential environmental impacts.

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.

To investigate the accumulation characteristics of gas hydrates in the Shenhu Area of the South China Sea from a multi-property perspective,we performed a joint interpretation of marine Controlled-Source Electromagnetic (CSEM) and multi-channel seismic data. The four stratigraphic interfaces identified from the 2D constrained inversion resistivity profiles of two marine CSEM lines correlate well with seismic interfaces T1-T4. A deeply-rooted high-resistivity anomaly zone, extending upward over 3 km in width, couples with chaotic seismic reflections. This correlation confirms the development of mud diapirs and indicates a high thermal maturity of deep source rocks, thereby establishing a foundation for thermogenic gas supply. The CSEM resistivity profiles demonstrate significant advantages in delineating gas migration pathways and reservoir boundaries. They reveal that fault systems control the vertical transport of thermogenic gas,directly influencing the spatial distribution of gas hydrate and free gas. This underscores the effectiveness of integrated seismic-electromagnetic interpretation in analyzing the reservoir transport system. Furthermore,the inverted resistivity values are consistent with drilling results: intervals within the gas hydrate stability zone exhibit high-resistivity anomalies (approximately 5 similar to 10 Omega m),whereas sections without hydrate show no such anomalies. The saturation distribution profile, obtained through joint seismic-CSEM inversion, clearly delineates the saturation characteristics of gas hydrate and free gas. The average saturations at wells W02 and W07 are 0.35 and 0.34,respectively,which deviate by less than 10% from the mean log-derived saturation values (0.32 and 0.33). The integration of marine CSEM and multi-channel seismic data significantly enhances the understanding of gas migration and reservoir systems, thereby contributing to reduced drilling risks.

This study presents the first application of a deep-towed transmitter–receiver marine controlled-source electromagnetic (TTR-MCSEM) system for gas hydrate exploration in the Shenhu area of the South China Sea. High-resolution electromagnetic data were acquired along a 13 km transect using dynamic source–receiver offsets and a 500 A transmitter. The results reveal the following: (1) unprecedented near-seafloor resolution (20~100 m) for the precise delineation of hydrate-bearing caprock, surpassing conventional ocean-bottom electromagnetic systems; (2) laterally continuous high-resistivity anomalies (~10 Ω·m) extending from the base of the gas hydrate stability zone to the seafloor, which correlate with seismic bottom-simulating reflector (BSR) distributions and suggest heterogeneous hydrate saturation; and (3) fault-controlled fluid migration pathways that supply hydrate reservoirs and lead to seabed methane seepage at structural highs. Through 2D inversion, we show that the inverted resistivity values (~10 Ω·m) are slightly higher than those obtained from resistivity logs (~5 Ω·m). Saturation values derived from inverted resistivity exhibit remarkable consistency with well-log-based measurements. The high efficiency of the system confirms its potential for the transformative quantitative assessment of hydrate systems, seafloor massive sulfides, and marine geohazards.

Reservoir classifications are a pivotal step in obtaining comprehensive understandings of reservoirs and formulating rational and effective development strategies. Fine-grained natural gas hydrate reservoirs situated on deep-sea continental slopes are characterized by varying degrees of fracture development and complex pore characteristics. However, there is no targeted and effective quantitative method for classifying hydrate reservoirs, resulting in inadequate reservoir characterization. This study, anchored by electrical imaging data, integrates core analyses, laboratory experiments, and logging-while-drilling data to investigate pore space types and categorize the natural gas hydrate reservoirs in the Qiongdongnan Basin, South China Sea. Drawing on the distinctive electrical image log response characteristics of different reservoir types, a method to identify the reservoir type is devised, and a reservoir classification model is proposed based on the characteristic parameters of the porosity spectrum. This finding highlights the advantages of using porosity-spectrum technology to identify strongly heterogeneous natural gas hydrate reservoirs. Research reveals that the natural gas hydrate reservoirs in the study area possess dual storage spaces consisting of fractures and pores. On the basis of the types of storage space, configuration relationships, and filling degrees of natural gas hydrates, reservoir types are categorized into three types: the fracture-pore type, strong hydrate-fracture type, and weak hydrate-fracture type. These three types of reservoir exhibit varying degrees of hydrate occurrence spaces, which results in significant differences in the responses of electrical image logs. The porosity-spectrum analysis method using electrical image logs effectively distinguishes the reservoir types. By extracting and optimizing porosity-spectrum parameters, such as P50 (which represents the value on the horizontal axis for the porosity spectrum that corresponds to 50% of the cumulative frequency distribution on the histogram) and VOSI (secondary pores), establishing standards for classifying reservoir types and achieving comprehensive identification of well-section reservoir types, this method is highly effective in identifying hydrate reservoir types on the basis of the porosity spectrum. This research provides a valuable reference for evaluating natural gas hydrate reservoirs with fracture-matrix dual storage spaces in the Qiongdongnan Basin and in exploration areas worldwide with similar geological environments, offering insights into the quantitative analysis and application of electrical image logs.

Gas hydrates are mostly concentrated in silt-clay sediments, and the sediment properties (including the particle size and mineral composition) play an important role in controlling gas hydrate accumulation. The northern part of the South China Sea (SCS) is one of the most representative areas with fine-grained gas hydrate reservoirs. In this study, the particle size and mineral composition of 597 sediment samples from gas hydrate reservoirs and adjacent layers at seven sites in the Dongsha, Shenhu, and Qiongdongnan areas, northern SCS, were analyzed, and the sediment properties of the fine-grained gas hydrate reservoirs were determined. Specific surface area and irreducible water saturation analyses were conducted to reveal the controlling significance of the sediment properties on the accumulation of gas hydrates in the fine-grained sediments. The results show that the mineral composition has a controlling effect on the gas hydrate reservoirs and nongas hydrate layers. Due to the adsorption and constraint of illite and smectite mixed layers (I/S) on the gas and fluid and the complex microstructure of I/S, the gas hydrate reservoirs have low I/S and high felsic mineral contents. The sediment particle size has a significant controlling effect on the gas hydrate saturation and morphology in the fine-grained reservoirs. Dispersed low saturation gas hydrates are mainly formed via pore filling, and they appear in the gas hydrate reservoirs dominated by >16 mu m sediment particles. Visible high saturation gas hydrates are mainly formed via particle displacement, and they appear in the gas hydrate reservoirs dominated by <8 mu m sediment particles. The results of this study are helpful for further revealing the law of gas hydrate enrichment in fine-grained sediments and have important significance for gas hydrate exploration and development and its environmental effects.

Natural gas hydrates are extensively distributed across terrestrial permafrost zones and continental margins worldwide [...]

In fine-grained marine sediments dominated by clayey silt and silt, gas hydrate saturation has been shown to have a highly nonlinear relationship with well-logging data and reservoir petrophysical properties. This complexity arises from such factors as strong reservoir heterogeneity, high clay content, and low permeability. Therefore, accurately predicting hydrate saturation has remained a significant challenge. On the basis of conventional geophysical well-logging techniques, in this study, we applied five machine learning (ML) algorithms to estimate hydrate saturation. We used measured saturation data and well-log records from three sites in the Shenhu Area to develop predictive models and applied them to estimate hydrate saturation at unmeasured locations. According to our results, resistivity and Delta-T compressional wave from a monopole source (an acoustic logging parameter, DTCO) had the strongest correlation with hydrate saturation. Using either parameter alone or their simple combination, however, resulted in limited predictive accuracy. The optimal feature set to predict hydrate saturation typically includes 3-4 types of logging data, and it must contain at least either resistivity or DTCO. Additionally, because gamma ray (GR) logging has low correlation with other parameters, it offers complementary information that is independent of core features. This enhances the predictive accuracy of ML models under complex lithological conditions. Among the five ML algorithms evaluated, extreme gradient boosting (XGBoost) achieved the best predictive performance. It attained a high coefficient of determination (R 2) of 0.9242 on the test set, and its predicted saturation curve closely aligned with the measured data. In this study, we demonstrated the accuracy and reliability of ML algorithms to predict hydrate saturation. These results offer a valuable technical approach to quantitatively evaluate hydrate resources in the Shenhu Area and provide theoretical support for the industrial development of gas hydrates.

The ultimate enrichment level and quantity of gas hydrate resources are influenced by the dynamic process of accumulation and preservation. High-resolution 3-D seismic data, logging while drilling (LWD), pressured coring, and in situ testing were used to characterize the dynamic accumulation and preservation of the trial production high-grade gas hydrate reservoir (HGGHR) in the Shenhu area. Through seismic variance analysis and ant-tracking, we found that newly identified mud diapir-associated faults with three development stages controlled the migration and accumulation of gas hydrate and shifted the base of the gas hydrate stability zone (BGHSZ), resulting in dynamic accumulation and dissociation of gas hydrates. The recognized double bottom simulating reflectors (BSRs) were concluded to have been formed due to the shift of the BGHSZ caused by the variational equilibrium conditions. The interval between the double BSRs was inferred to be a disequilibrium zone where gas recycling occurred, contributing to the coexistence of gas hydrates and free gas and the dynamic formation of the HGGHR. Multiple gliding faults formed within the GHSZ in the late period have altered the HGGHR and control the present thickness and distribution of the gas hydrates and free gas in the hanging wall and footwall. Under the influence of geothermal fluids and the fault system associated with the mud diapir, the HGGHR experienced dynamic accumulation with three stages, including early accumulation, medium-term adjustment, and late alteration and preservation. We conclude that four factors affected the formation, distribution, and occurrence of the HGGHR: the geothermal fluids accompanying the deep mud diapir below the reservoir, the dual supply of thermogenic gas and biogenic gas, the recycling of hydrate gas beneath the BGHSZ, and the post-gas hydrate faults developed within the GHSZ. A geological model illustrating the dynamic formation of the trial production HGGHR was proposed, providing a reference for future exploration of HGGHRs with a great production potential in deepwater settings.

In this study, we use petroleum systems modeling (PSM) to quantitatively simulate the uncertainty of biogenic gas generation modes and their impact on the spatial distribution and resource assessment of gas hydrates in the Baiyun Sag, South China Sea. The results are as follows: (1) Biogenic gas generation is significantly affected by thermal state and organic matter type. Low temperature is a primary reason for gas hydrate occurrence in shallower sediments when sufficient methane gas is present. This may be due to higher thermal conductivity of the overlying sediments, slower sediment burial rates, or other geological processes. (2) Natural gas hydrate resources are significantly controlled by biogenic gas generation. In addition to the thermal conditions of the source rock or sediment, the nature of the organic matter is another crucial factor. Generally, low-temperature methanogens produce more methane gas because they require less energy, whereas high-temperature methanogens require more energy and thus produce less methane gas. (3) The biogas generation thermal model is key to controlling the location and quantity of natural gas hydrate resources. The three possible gas-phase models, K0, K1, and K2 (representing different methanogens), produce varying amounts of methane gas over time, resulting in different amounts of natural gas hydrate resources. Additionally, the preservation of various methanogens in biogas source rocks can alter reservoir formation locations, influencing the scale and genetic model of natural gas hydrate resources.

"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.

The Mesozoic subduction zone over the Dongsha Waters (DSWs) of the South China Sea (SCS) is a part of the westward subduction of the ancient Pacific plate. Based on the comprehensive interpretation of deep reflection seismic profile data and polar magnetic anomaly data, and the zircon dating results of igneous rocks drilled from well LF35-1-1, the Mesozoic subduction zone in the northeast SCS is accurately identified, and a Mesozoic subduction model is proposed. The accretion wedges, trenches, and igneous rock zones together form the Mesozoic subduction zone. The evolution of the Mesozoic subduction zone can be divided into two stages: continental subduction during the Late Jurassic and continental collision during the late Cretaceous. The Mesozoic subduction zone controlled the structural pattern and evolution of the Chaoshan depression (CSD) during the Mesozoic and Neogene eras. The gas source of the hydrate comes from thermogenic gas, which is accompanied by mud diapir activity and migrates along the fault. The gas accumulates to form gas hydrates at the bottom of the stable domain; BSR can be seen above the mud diapir structure; that is, hydrate deposits are formed under the influence of mud diapir structures, belonging to a typical leakage type genesis model.

AbstractThe particle size of sediments below the seabed is a crucial factor affecting the formation and enrichment of gas hydrates. Apart from the formation and enrichment law of gas hydrate in coarse‐grained sediments (dominated by a sandy‐sized fraction), in the fine‐grained sediments (<62.5 μm) which accounts for more than 90% of offshore gas hydrate resources globally, the control effect of sediment particle size on gas hydrate is still unclear. Therefore, understanding the relationship between the fine‐grained sediment particle size and gas hydrate enrichment is essential for revealing the global distribution and dynamic evolution of gas hydrates. Here, we analyzed the vertical gas hydrate saturation, particle size parameters of sediments, whole‐rock minerals, and clay mineral components based on drilling data and sediment samples from fine‐grained gas hydrate reservoirs (GHRs) in the Shenhu area of the northern South China Sea. The results show that in fine‐grained sediments, the coarse particles cannot improve the reservoir quality or enrich the gas hydrate because many fine particles fill the intergranular pores formed by the coarse particles. Meanwhile, the fine particles were dominated by clay minerals, especially in the illite/smectite mixed layer, which significantly reduced the permeability of the sediment layer and was not conducive to the enrichment of gas hydrates. Moreover, sedimentary processes directly control the sediment particle size and mineral composition, which play an essential role in controlling GHRs at the macroscale. In the fine‐grained sediments, very fine sediments (<8 μm) have a more significant negative impact on gas hydrate enrichment.

The complex contacts between gas hydrate and free gas have been confirmed by gas hydrate pilot production in the Pearl River Mouth Basin, South China Sea. The laminated clay silt reservoirs have high amplitude reflections which may be filled with different saturations of gas hydrates, free gas and the coexistence between gas hydrate and free gas. To distinguish the variations of amplitude reflections caused by different reservoirs properties below the bottom simulating reflection, we combine the forward modelling, pre-stack gathers with different incident angles and well log analysis to conduct the seismic responses. A number of geological models are established with variable saturations and different interfaces between gas hydrate and free gas. First, we analyse the seismic and well log responses at Sites W11, W01 and W17 near the production test area. Then, we perform the forward modelling to quantify the differences among seismic reflections with different saturations, thickness, incident angles and strata dips in free gas- or gas hydrate-bearing geological models. We extract the seismic amplitudes along the bottom simulating reflection and other layers to compare with the amplitudes generated from forward modelling. The results indicate that the inclined intervals below the bottom simulating reflection have high amplitude, continuous reflection and polarity reversal which may be caused by thin gas reservoir and the interlayered gas hydrate and free gas with different saturations. The top interfaces of the gas hydrate- and free gas-bearing layers show typical Class III amplitude versus offset and exhibit high amplitude reflections at seismic data with near, mid and far-incident angles, which are easy to distinguish. Seismic response of far-incident angle can be used to identify the coexistence of gas hydrate and free gas.

A detailed understanding of the distribution and potential of natural gas hydrate (NGHs) resources is crucial to fostering the industrialization of those resources in the South China Sea, where NGHs are abundant. In this study, this study analyzed the applicability of resource evaluation methods, including the volumetric, genesis, and analogy methods, and estimated NGHs resource potential in the South China Sea by using scientific resource evaluation methods based on the factors controlling the geological accumulation and the reservoir characteristics of NGHs. Furthermore, this study compared the evaluation results of NGHs resource evaluations in representative worldwise sea areas via rational analysis. The results of this study are as follows: (1) The gas hydrate accumulation in the South China Sea is characterized by multiple sources of gas supply, multi-channel migration, and extensive accumulation, which are significantly different from those of oil and gas and other unconventional resources. (2) The evaluation of gas hydrate resources in the South China Sea is a highly targeted, stratified, and multidisciplinary evaluation of geological resources under the framework of a multi-type gas hydrate resource evaluation system and focuses on the comprehensive utilization of multi-source heterogeneous data. (3) Global NGHs resources is nx 1015 m3, while the NGHs resources in the South China Sea are estimated to be 1013 m3, which is comparable to the abundance of typical marine NGHs deposits in other parts of the world. In the South China Sea, the NGHs resources have a broad prospect and provide a substantial resource base for production tests and industrialization of NGHs.

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.

Accurate evaluation of the distribution characteristics and physical properties of gas hydrate reservoirs is crucial for estimating gas hydrate resources,guiding development and utilization strategies,and understanding environmental impacts.Based on high-precision 3D seismic and well-logging data acquired in the Shenhu area,this paper presents a comprehensive method for discriminating between hydrate layers,free gas layers,and coexistence layers using integrated logging-seismic responses.Our results show that the gas hydrate layer and free gas layer at the W17 station can be accurately identified by combining post-stack seismic profiles with detailed analysis of logging curves.Above the BSR,a hydrate layer is characterized by relatively high seismic velocity,strong amplitude reflections,poor transverse continuity,and high resistivity and velocity values.In contrast,the underlying free gas layer exhibits low seismic velocity,low-frequency weak amplitude reflections,and low resistivity and velocity values.This study provides a robust basis and valuable reference for informed decision-making regarding gas hydrate reservoir identification,resource evaluation,exploration,and trial production activities.

Previous studies indicate that mass transport deposits are related to the dynamic accumulation of natural gas hydrates and gas leakage. This research aims to elucidate the causal mechanism of seabed seepage in the western region of the southeastern Qiongdongnan Basin through the application of seismic interpretation and attribute fusion techniques. The mass transport deposits, bottom simulating reflector, submarine mounds, and other phenomena were identified through seismic interpretation techniques. Faults and fractures were identified by utilizing variance attribute analysis. Gas chimneys were identified using instantaneous frequency attribute analysis. Free gas and paleo-seepage points were identified using sweetness attributes, enabling the analysis of fluid seepage pathways and the establishment of a seepage evolution model. Research has shown that in areas where the mass transport deposits develop thicker layers, there is a greater uplift of the bottom boundary of the gas hydrate stability zone, which can significantly alter the seafloor topography. Conversely, the opposite is true. The research indicates that the upward migration of the gas hydrate stability zone, induced by the mass transport deposits in the study area, can result in the rapid decomposition of gas hydrates. The gas generated from the decomposition of gas hydrates is identified as the principal factor responsible for inducing seabed seepage. Moderate- and low-speed natural gas seepage can create spiny seamounts and domed seamounts, respectively.

Gas hydrate drilling expeditions in the Pearl River Mouth Basin, South China Sea, have identified concentrated gas hydrates with variable thickness. Moreover, free gas and the coexistence of gas hydrate and free gas have been confirmed by logging, coring, and production tests in the foraminifera-rich silty sediments with complex bottom-simulating reflectors (BSRs). The broad-band processing is conducted on conventional three-dimensional (3D) seismic data to improve the image and detection accuracy of gas hydrate-bearing layers and delineate the saturation and thickness of gas hydrate- and free gas-bearing sediments. Several geophysical attributes extracted along the base of the gas hydrate stability zone are used to demonstrate the variable distribution and the controlling factors for the differential enrichment of gas hydrate. The inverted gas hydrate saturation at the production zone is over 40% with a thickness of 90 m, showing the interbedded distribution with different boundaries between gas hydrate- and free gas-bearing layers. However, the gas hydrate saturation value at the adjacent canyon is 70%, with 30-m-thick patches and linear features. The lithological and fault controls on gas hydrate and free gas distributions are demonstrated by tracing each gas hydrate-bearing layer. Moreover, the BSR depths based on broad-band reprocessed 3D seismic data not only exhibit variations due to small-scale topographic changes caused by seafloor sedimentation and erosion but also show the upward shift of BSR and the blocky distribution of the coexistence of gas hydrate and free gas in the Pearl River Mouth Basin.

Gas chimneys are key pathways for geofluid vertical migration; therefore, deciphering their formation and evolution is crucial for hydrocarbon exploration and geohazard risk assessment. However, the influences of ambient conditions (e.g. bathymetry, tectonics, sediment supply flux) on gas chimney development have not been thoroughly investigated. Using high-resolution 3D seismic data, we have identified 59 gas chimneys beneath the Shenhu Slope (a gas hydrate test production area on the northern South China Sea margin), 35 of which intersect faults. Above fault interfaces, internal seismic structures are dominated by chaotic discontinuous reflections. Internal structures below interfaces display more continuous reflections, which are also apparent in gas chimneys, not intersecting faults. A higher degree of chaotic or discontinuous seismic reflections may indicate more fragmented networks. This may occur due to increased fluid flow along faults and concomitant fluid overpressure. The present-day undulating seafloor comprises the inter-canyon (IT) region, intra-canyon (IN) region and flat slope (FD) region downstream of canyons. Gas chimneys beneath IT and IN regions exhibit elongated elliptical shapes in the plane, with the long axis azimuth (sub-) parallel to the main strike of canyons. Chimneys beneath the IT region have larger heights than those beneath the IN and FD regions. Thicker sediment in the IT region corresponds to a higher overburden pressure, which may induce stronger overpressure in the subsurface reservoir region. This overpressure may promote chimneys gathering in the IT region. Canyons' main directions are likely to limit hydraulic fracturing due to maximum gradient boundaries between overlying sediment stress fields. This study provides insights into gas chimney distribution, morphology and structure evolution in relation to bathymetry and fault conditions. It contributes to an improved understanding of how geofluids migrate in marginal ocean basins.