Quantitative analysis method of seismic attributes under limited well control conditions and its application to source rock prediction

Abstract

A quantitative analysis method of seismic attributes under limited well control conditions is proposed to evaluate the exploration potential of a basin and also predict the distribution of source rocks in the early exploration stage. Based on the total organic carbon (TOC) laboratory testing, in this study, the thickness of source rocks is divided by drilling and outcrop. A geological model is established on the basis of the petrophysical characteristics of source rocks and surrounding rocks. Applying a one-dimensional forward modeling of real drilling, which integrates two-dimensional forward modeling method with replacement experiments of source rocks, we analyze the relationship between geological characteristics of source rock and its seismic response and retrieve geological factor in changes of seismic attributes. Given the relationship between seismic reflection characteristics and geological features, the distribution of source rocks can be quantitatively predicted by using the seismic attributes. This method combines test analysis, well logging, and seismic method together and gives an explicit geological significance of seismic attributes. It provides an effective method to predict source rocks under fewer drillings in the early exploration stage. Finally, application to a basin L confirms that this method proposed in this paper can effectively predict the distribution characteristics of source rocks and also provide the important basis to evaluate the exploration potential.