Preliminary analysis of seismic attenuation and heterogeneities in Weiyuan Shale Gas Field: Coda Q and Peak delay time analysis

• DOI: 10.5194/egusphere-egu24-9417
• Publication Date: 2024-03-08T19:51:51Z
• Authors: Aqeel Abbas; Luca De Siena; Hongfeng Yang; Simona Gabrielli; Wei-Mou Zhu
• Keywords: Coda; Shale Gas

During hydraulic fracturing (HF) stimulation in unconventional reservoir development, seismic attenuation significantly affects high frequency microseismic data. Analyzing parameters, including scattering and absorption, provides valuable insights into properties changes that result from HF injections. These parameters were mapped 3D using the MuRAT (multi-resolution tomography) software with a dataset of approximately 32,000 events over two years Weiyuan shale gas field (WSGF). Firstly, coda quality factor Qc (intrinsic absorption), which quantifies wave energy loss, is calculated at large lapse time three bands (3, 6 9 Hz). Subsequently, we measure peak delay time, lag between direct S-wave onset highest amplitude arrival. Our preliminary results show has strong absorption lower frequencies specific volumes compared to higher frequencies. Meanwhile, times indicate consistently stronger along anticline Molin fault structures across all bands. We propose observed associated injected fluid, while linked pre-existing structural heterogeneities unmapped faults.