Integration of 3C-3D seismic data and well logs for rock property estimation

Todor I. Todorov

Well log measurements and 3C-3D seismic data are integrated for rock property estimation using three methodologies: inversion, geostatistics, and multi-attribute analysis. The 3C-3D seismic data set and well logs are from the Blackfoot field, Alberta. Conventional model-based inversion is applied to the P-P data to estimate the acoustic impedance. 3-D converted-wave (P-S) inversion for shear velocity is developed that computes a P-S weighted-stack followed by conventional inversion algorithm. An approximation formula for the incident angle in the P-S case has been derived and tested successfully versus ray-tracing. Geostatistical methods of kriging, cokriging, and stochastic simulation are used for sand-shale distribution mapping and time-to-depth conversion. Linear multi-regression and neural networks are used to derive a relationship between porosity logs and a set of seismic attributes. Porosity, sand percentage and sand thickness are used to generate a hydrocarbon volume map.