Methods for Generation of Fracture Density Maps from Seismic Data

BACKGROUND

Fractures, pre-existing planes of weaknesses in rock units, play a critical role in determining the production potential of reservoirs that are developed through lateral/horizontal drilling and hydraulic fracturing (“fracking”).  Knowledge of fracture orientation and/or extent is key to production in formations. Rock fractures contribute to porosity and, if they are open, have the potential to contribute substantially to the permeability of a formation. Permeability in producing formations is necessary and highly desirable as it provides a pathway for oil to be pushed or drawn to the borehole so that it can be extracted. Knowledge of or an estimate of where a reservoir is fractured internally is an important consideration in the process of selecting a drill site for exploration or production purposes.

SUMMARY OF TECHNOLOGY

Statistically combine multiple seismic attributes for generating a map of the spatial density of fractures by interpreting the formation of interest in 3D seismic volume first to create its time structure map, creating depth structure of the formation of interest from its time structure map, and then extract of a number of attributes, such as phase, frequency and amplitudes, from the time structure map, project the fracture density onto the top of the target formation, finally combine these attributes using a statistical method known as Multi-variant non-linear regression to predict fracture density.  Geostatistical methods can be used for depth conversional, although other methods could be used instead.

POTENTIAL AREAS OF APPLICATION

• Oil and Gas Exploration

STAGE OF DEVELOPMENT

• Working model