Combining multiseismic attributes with an extended octree quantization method

Abstract

Seismic interpreters and processors encounter ever-increasing volumes of seismic attributes in geophysical exploration each year. Multiattribute integration and classification improve the ability to identify geologic facies and reservoir properties, such as thickness, fluid type, fracture intensity, and orientation. Simple color mixing technology allows us to display three attributes simultaneously. To overcome this limit, we extend from three nodes to up to eight nodes octree color quantization originated from image processing of compressing colors to handle eight groups of attributes to form a single attribute. We can then apply the group reduction criterion for geophysical data classification to reveal common geologic targets while preserving the small variations or thin layers often present in hydrocarbon reservoirs. By combining multiple attributes, we hope to see all individual geologic features in the same image but also channels that might not be visible in any single attribute and to focus on major geobodies through group reduction classification on combined data. We first applied the method to a 2D section of poststack seismic data and well logs to test its validity, and then we further used it on scaled curvatures and other 3D seismic attributes to showcase the aforementioned benefits. Storage efficiency is a noted additional advantage of octree. However, the importance of selecting relevant attributes for octree application cannot be underestimated and requires the involvement of experienced seismic interpreters.