Geochemical processes in tight gas hydraulic fracturing stimulation / Геохимические процессы при стимулировании гидроразрыва пласта плотного газа

Hydraulic fracturing has sparked a global revolution in unconventional oil and gas extraction, enabling the exploitation of unconventional resources that comprise approximately 80% of the world’s total energy reserves. With the continuous advancement and application of hydraulic fracturing technology, unconventional hydrocarbon resources represented by tight oil/gas, shale oil/gas, coalbed methane, and oilshale have developed rapidly. However, while significantly increasing unconventional hydrocarbon production, hydraulic fracturing has also induced a series of engineering and environmental issues that warrant serious attention. During the fracturing process, substantial volumes of fluid containing diverse chemical additives are injected into subsurface formations. This process inevitably disrupts the original water-rock-gas equilibrium of the formation, inducing a series of chemical reactions that alter the quality of the flowback water and cause various forms of reservoir damage such as secondary mineral precipitation, clay swelling, and particle migration, thereby reducing fracturing efficiency and gas well productivity.
In response to these challenges, this book takes the Sulige Gas Field (the largest natural gas field in China) asthe study area,systematically investigatesthe geochemical processes associated with hydraulic fracturing in tight sandstone gas reservoirs through integrated field observations, laboratory experiments, and model simulations. By characterizing the mineralogy, reservoir properties, and post-fracturing water chemistry, this research elucidates the geochemical processes active during hydraulic fracturing of tight sandstones, thereby providing theoretical and technical foundations for fluid optimization and process enhancement. Meanwhile, regional water environmental issues induced by hydraulic fracturing were further explored, focusing on the identification of potential groundwater contamination in the Sulige Gas Field and discussion on the management and resource utilization of flowback water. <...>