Gas channels and chimneys detection using post-stack seismic attributes, simian field, offshore west Nile Delta, Egypt

The West Delta Deep Marine region has substantial prospects for extracting oil and gas. The area is also known for its distributed and disconnected channel systems and gas chimneys. The Simian field is particularly intriguing within this region. Gas chimneys and pockmarks are frequently observed on the seafloor. Pockmarks are formed when gas or fluid is released, causing depressions. These characteristics have the potential to influence the stability of the seabed and present hazards to oil rigs in proximity. To reduce the risks associated with these hazards, it is essential to have a thorough comprehension of the geological characteristics involved. The primary objective of our study is to identify and delineate gas channels and chimneys and the associated geologic features through the analysis of seismic attributes and the construction of three-dimensional models. By applying multiple seismic attribute classes such as the cosine of the phase, variance, and envelope, the detection of these hazards and associated features can be improved. We were able to identify and isolate areas of high-intensity brightness in the vicinity of the Simian gas channel. These high-intensity brightness zones serve as clear indicators of gas seepage and the movement of gas. In addition, there is substantial evidence of gas being discharged from a high-pressure zone upwards to the seafloor through the gas chimney and eventually creating pockmarks that pose a serious hazard area to the hydrocarbon production process. Upon completion of this study, after linking the presence of the subsurface marine geological features and the hazardous risk these features might propose. The optimal site within the study area for the placement of an oil rig with the aim of mitigating the impacts of capillary action is recommended. The results enhance risk avoidance and regulatory measures in this highly significant field.