A new methodology is presented for delineating oil and gas reservoirs using surface lineament and fracture analysis. The methodology applies both engineering and geological analyses of surface lineaments and fractures mapped from satellite images and aerial photos to quantitatively delineate new reserves in a mature field. The methodology is illustrated by analyzing the surface lineaments and fractures, and subsurface structures in Osage County, OK. Five indicators of subsurface structural complications were identified. They are surface lineaments, residual surface-fracture density, residual surface-fracture frequency, residual surface-fracture orientation complications, and surface circular and arcuate anomalies.
The methodology presented in this paper provides a cost-effective approach for identifying potential subsurface oil and gas traps. It can also be used to indicate where additional reserves are located in mature fields, prioritize locations for exploratory drilling, or select areas for geochemical and geophysical surveys in frontier regions.
The United States is largely a mature producing province. To maintain domestic oil production or reduce the rate of decline, new reserves must be delineated in mature fields. Since easy-to-find reservoirs have already been found and the remaining ones are more likely located in subtle structural and/or stratigraphic traps, exploration in mature fields is becoming increasingly more difficult and more expensive and sophisticated new techniques must be employed. Furthermore, different exploration techniques have to be integrated in order to effectively identify subtle features of potential oil and gas reservoirs. In this paper, an innovative and cost-effective methodology is presented using surface lineament and fracture analysis for delineating new reserves in a mature field.
The use of surface lineaments and fracture analysis for hydrocarbon exploration is not a new concept. Throughout the history of the oil industry, various approaches have been used to infer subsurface oil and gas accumulations and to analyze production performance using surface lineament and fracture information. However, most of the techniques presented in previous studies are more qualitative than quantitative. Of the few quantitative techniques reported in the literature, most were based on an individual characteristic, such as density or intensity, of surface linear features. This paper presents a new methodology and a case study on how to use surface lineament and fracture analysis for oil and gas exploration in a mature field. The methodology was developed through an integration of geological and engineering analyses of multiple surface features, including lineaments, fractures, and circular and arcuate anomalies. The techniques involved in the methodology require geological interpretations and extensive numerical calculations.
Remote sensing data, such as satellite images and aerial photos, are first interpreted to map surface features, which are subsequently digitized for quantitative analyses. An orientation analysis is performed of surface lineaments and fractures to identify the regional structural styles. Five structural indicators are used to identify and rank priority locations for exploratory drilling and/or more expensive surveys. The methodology is demonstrated through a case study to generate exploration leads for potential new reserves in Osage County, OK.
The methodology for delineating subsurface oil and gas reservoirs using surface lineament and fracture analysis consists of the following elements:
Interpretations of remote sensing data for mapping surface features
Geological and orientation analyses of surface linear features for identifying regional structural styles