Interpretation of Subsurface Hydrocarbon Shows
Tim T. Schowalter ², Paul D. Hess ³

Table of Contents

ABSTRACT

INTRODUCTION

CLASSIFICATION OF HYDROCARBON PHYSICAL MODES OF OCCURENCE

Show types

Continous Phase Shows (Type 1)

Residual Shows (Type II)

Molecular-Scale Dissolved Hydrocarbon Phase (Type III)

Hydrocarbons Incorporated in Kerogen (Type IV)

Implication of Modes of Occurence

Identification of Type One Shows

Hydrocarbon Saturation

Fluid Recovery

Extrapolation Case History -Buffalo Field

EXPLORATION OF TYPE 1 SHOWS IN COMPLEX STRATIGRAPHIC TRAPS

Simple Stratigraphic Trap Model

Complex Stratigraphic Trap Model

Transition Zone Characteristics

Waste Zone Characteristics

Exploration Implications of Transition and Waste Zones

SHOW INTERPRETATION-EXTRAPOLATION CASE HISTORIES

Waste zone

Pay Dirt Field- Gas Waste Zone

Transition Zone Example

Poker Chip Field

TEST CASE

Case histories related to hydrocarbon shows-1982

Buffalo field, Harding County, South Dakota Structural map (Fig. 5)

Core and log data (Fig. 6; Fig. 21)

Log and test data (Fig. 19)

Cross section, western part of field (Fig. 20)

Capillary pressure curves (Fig. 7; Fig. 22)

Pay Dirt field Structural map (Fig. 11)

Cross section (Fig. 12)

Core and log data (Fig. 13; Fig. 14)

Capillary pressure curves (Fig. 15; Fig. 16)

Poker Chip field Core and log data (Fig. 17)

Capillary pressure curves (Fig. 18)

SUMMARY AND CONCLUSIONS

REFERENCES

 

Acknowledgments:

² Mosbacher & Pruet Oil Producers, Denver, Colorado.
³ B.W.A.B., Inc., Denver, Colorado.

We thank Shell Oil Co., Houston, Texas; Kirkwood Oil and Gas, Casper, Wyoming; and Koch Exploration Co., Wichita, Kansas, for the release of materials presented in this report. Personal acknowledgments to Don Hartman, John McCallum, and Steve Kirkwood for their contributions in assembling the geologic framework for the field studies presented. Some illustrations were adapted from Core Laboratories instructional manuals.

© 1994 American Association of Petroleum Geologists