Exploratory Significance of Pressure Profiling Techniques
Authors: McCleskey R.W. 
Published: December 2007

American Institute of Mining, Metallurgical, and Petroleum Engineers, Inc.

This paper was prepared for the 43rd Annual Fall Meeting of the Society of Petroleum Engineers of AIME, to be held in Houston, Tex., Sept. 29-Oct. 2, 1968. Permission to copy is restricted to an abstract of not more than 300 words. Illustrations may not be copied. The abstract should contain conspicuous acknowledgment of where and by whom the paper is presented. Publication elsewhere after publication in the JOURNAL paper is presented. Publication elsewhere after publication in the JOURNAL OF PETROLEUM TECHNOLOGY or the SOCIETY OF PETROLEUM ENGINEERS JOURNAL is usually granted upon request to the Editor of the appropriate journal provided agreement to give proper credit is made. provided agreement to give proper credit is made. Discussion of this paper is invited. Three copies of any discussion should be sent to the Society of Petroleum Engineers office. Such discussion may be presented at the above meeting and, with the paper, may be considered for publication in one of the two SPE magazines.

Anomalies observed on log-derived "Pore Pressure Profiles" may be correlated in the Pressure Profiles" may be correlated in the same manner as conventional "SP" or "Resistivity" curves. Since the character (i.e., detail, shape) of the curves remains whole regardless of whether the section grades from sand to shale, or vice versa, the resulting conclusion is that such correlations trace equal time-rock units. Therefore, the profiles should be useful for correlating across growth faults.

Additionally, cross-sections resulting from pore pressure profile correlations seem to pore pressure profile correlations seem to present for study a picture history of present for study a picture history of sediment and hydrocarbon accumulation. That is, isobaric surveys may be used to study migration routes of hydrocarbons. The profiles therefore offer themselves as profiles therefore offer themselves as potentially powerful exploration tools. potentially powerful exploration tools. Last, a new theory suggesting a relationship between overpressure and temperature is advanced. Temperature seems to be related to overpressure through a common denominator, that being the amount of water retained in the shale sections.

Introduction

The technology of log-derived pressure data had an immediate and vital effect on drilling. Its progress in the field of exploration has been less evident. The reasons seem to be that explorationists have considered pressure profiling an engineer's tool, and as a rule engineers do not deal with exploration. The pressure profiling techniques to be discussed have been used successfully to predict pressures and select casing points. However, these may not be the most valuable uses of pressure profiling. An explorationist interested in profiling. An explorationist interested in the structure and stratigraphy of an area should be intrigued by the new insights offered by pressure profiling. Therefore, I will try to share some of the possible new uses that have stirred my interest.

First, I will show that correlations may be made using pore pressure profiles in place of conventional "SP" or "Resistivity" place of conventional "SP" or "Resistivity" correlations. A cross-section constructed from pressure profile correlations will then be studied. Such cross-sections seem to present a picture history of the hydrology present a picture history of the hydrology of sediment and hydrocarbon accumulation. This picture history holds the most intrigue for me. Such sections offer themselves as potentially powerful exploration tools. potentially powerful exploration tools.