Integrated Interpretation
Advances in geophysical data acquisition and interpretation have led to significant improvements in the remote imaging of earth structure and properties. However, when only a single data type is considered, ambiguities in the interpretation can remain. Integration of different geophysical data types allows the strengths of each to be exploited: this idea is at the center of the INTEGRATION approach in which seismic and well log data are integrated to determine the structure and properties of the earth.
Well logs provide a high-resolution measurement of the properties of a reservoir and the surrounding strata, however properties can only be determined in a small area local to the well. Often measurements of reservoir properties across the extent of a field are required. Geophysical methods provide the data necessary to investigate the earth between well locations.
Seismic data are commonly used to provide images of the sub-surface and develop high resolution geological models of structure and stratigraphy. Amplitude variation with offset (AVO) and inversion for acoustic and elastic impedance may also be used to constrain properties such as elastic moduli and density, however seismic data alone in many situations cannot give a complete picture of the reservoir.
It is clear that a careful combination of all three data types can supply information that is not available or is unreliable from any one data type alone. By integrating complementary sources of information and exploiting the strengths of each, estimates of rock properties such as hydrocarbon fluid, lithology and porosity can be obtained with greater confidence than from any one data type alone.
The INTEGRATION approach uses a range of workflows developed for the integrated interpretation of seismic and well log data within a consistent rock physics framework, to provide quantitative measurements of sub-surface rock properties, leading to improved reservoir characterization.