Skip to Main Content
Book Chapter

Natural Fractures in Core

Published:
January 01, 1990

Abstract

A natural fracture is defined as any cored fracture that existed in a volume of rock prior to initiation of drilling. The natural fracture geometry in a given core can be simple or complex. A simple geometry may consist of only one pervasive fracture set of regularly spaced, open fractures of similar trend with no evidence of slip or pressure solution. This common fracture trend reflects a fracturing stress field that remained essentially unchanged through a given period of time. Conversely, a complex fracture signature composed of several such fracture sets may reflect the cumulative effect of different stress events that occurred during specific spans of geological time (Nickelsen, 1976; Nickelsen and Hough, 1967; Engelder and Geiser, 1980). For example, these diverse stress events may be related to initial basin development, superposition, or orogenic stresses and subsequent epeirogenic uplift

The geometrical relationships and relative growth chronology between the fracture sets developed during one or several regional stress episodes are made even more complex by the effect of previously existing fractures an do ther regional structures such as depositional basins, buried fault zones, folds, and regionally persistent anisotropies inherited from earlier depositional and tectonic events. These preexisting structures at a large scale can affect the regional stress field, giving rise to diverse fracture sets that commonly can be grouped into regional fracture domains, each with a unique fracture signature (Kulander et al., 1980;Pollard et al., 1988). Similarly, primary or secondary structures at a local scale can affect later stress states to

You do not currently have access to this article.

Figures & Tables

Contents

AAPG Methods in Exploration

Fractured Core Analysis: Interpretation, Logging, and Use of Natural and Induced Fractures in Core

B. R. Kulander
B. R. Kulander
Department of Geological Sciences Wright State University Dayton, Ohio, U.S.A.
Search for other works by this author on:
S. L. Dean
S. L. Dean
Department of Geology University of Toledo Toledo, Ohio, U.S.A.
Search for other works by this author on:
B. J. Ward, Jr.
B. J. Ward, Jr.
Amoco Production Company Research Center Tulsa, Oklahoma, U.S.A.
1
Currently with Associated Fracture Consultants, Broken Arrow, Oklahoma, U.S.A.
Search for other works by this author on:
American Association of Petroleum Geologists
Volume
8
ISBN electronic:
9781629811260
Publication date:
January 01, 1990

GeoRef

References

Related

Citing Books via

Close Modal
This Feature Is Available To Subscribers Only

Sign In or Create an Account

Close Modal
Close Modal