Advances In The Study Of Natural Fractures In Deep And Unconventional Reservoirs

Advances in the study of natural fractures in deep and unconventional reservoirs

Advances in Geomechanics Research and Application for Deep Unconventional Reservoirs

Deep unconventional oil and gas reservoirs (such as shale oil/gas, tight oil/gas, coalbed methane (CBM), oil shale, etc.) are commonly characterized by geological and structural complexity, increased formation temperature and pressure, and complex in-situ stress fields. Geomechanics research is helpful to understand the in-situ stress of complex structures, faults and natural fracture systems in deep blocks. Field practice shows that insufficient geomechanics understanding can easily result in low drilling efficiency, long construction period, frequent occurrence of complex situations, and unsatisfactory fracturing effects. In recent years, geomechanics applied to drilling, completion, hydraulic fracturing, and production in unconventional reservoirs has achieved great progress, producing various advanced experimental and numerical approaches and applications. However, as the buried depth increases, the complicated geology conditions make it more and more difficult for the engineering reconstructions, which poses a great threat to the efficient development of deep resources. New knowledge and understandings of geomechanics are urgently needed to guide the development of unconventional oil/gas reservoirs, and the related theory, experiment and simulation studies are rapidly developing.

Differences in shale oil and gas reservoirs across various sedimentary environments: theories and applications, volume II

This Research Topic is Volume II of a series. The previous volume can be found here: Differences in Shale Oil and Gas Reservoirs across Various Sedimentary Environments: Theories and Applications The remarkable success of shale oil and gas production in North America has sparked worldwide interest in its significance. Notably, substantial shale oil and gas reserves have been discovered in China’s Cambrian and Ordovician-Silurian shales, which serve as the primary sources of production. Across the Asian continent, other shale plays exist, with several countries such as India, Saudi Arabia, and Pakistan actively pursuing development plans to identify additional resources. Globally, exploration and development of shale oil and gas in marine-continental transitional and terrestrial formations have resulted in significant breakthroughs, leading to the development of a host of geological theories and technologies for shale oil and gas extraction. With the availability of sophisticated exploration, drilling, logging, and advanced analysis and testing tools, in-depth investigation can be conducted on various aspects of shale formations, including the organic matter enrichment mechanism, sedimentation sequence, reservoir formation, oil and gas generation, drilling, and development. Additionally, the coexistence of similarities and differences in the characteristics of shale reservoirs formed in different sedimentary environments will undoubtedly impact the exploration and development of shale oil and gas. This Research Topic aims to bring together Original Research and Review articles addressing the similarities and differences of the geological theories of shale oil and gas in terrestrial, marine, and marine-continental transitional formations, which facilitates an overview of the latest advancement in how these geological theories can be applied in major shale oil and gas basins worldwide. Potential themes include, but are not limited to: • Management of global shale oil and gas development • Fractures and faults in shale • Mechanisms of organic natter enrichment • Stratification and sedimentary characteristics of shale deposits • Quantitative characterization of shale reservoirs • Pore space characterization of shale reservoirs • Shale oil and gas preservation conditions • Reservoir formation mechanisms of shale oil and gas • Drilling and development of shale oil and gas in different facies • Tight gas reservoir formation and conversion • Variations in shale reservoir characteristics