Production Logging as Used To Solve Water Injection Problems in the Huntington Beach Offshore Field
Authors: Yoelin Sherwin D. , Howald C. Douglas , Holbert Don R. 
Published: December 2007

In pressure transient testing, interzonal flow or the presence of just one unplugged sand tends to dominate the transient behavior and can easily mask damage in other sands. In those injectors where misleading data are suspected, combining pressure tests with spinner surveys and radioactive- tracer surveys can provide a sound basis for formulating remedial measures.

Introduction

The Huntington Beach oil field is approximately 41 miles southeast of Los Angeles on a high point along the Newport-Inglewood Fault trend in Orange County, Calif. (Fig. 1). The offshore portion lies in a westerly plunging anticline on the west side of the field. The heavily faulted offshore structure contains a number of thin, minor reservoirs, and three extremely thick, major reservoirs (400 to 800 ft in gross thickness). The thicker reservoirs, composed of continuous, Upper Miocene, unconsolidated sands and interbedded shales, are known as the Jones, the Upper Main and the Lower Main. Waterflooding is currently in progress in the Jones and the Lower Main. The Jones reservoir is divided vertically into two sections (each about 350 ft thick) by a 60-ft continuous shale bed located near the midpoint of the reservoir. This shale break allows independent flooding operations to be conducted in both the upper and lower zones. The Lower Main reservoir has no significant shale beds and the total interval (500 to 650 ft thick) is being flooded in a single, full-zone operation. Extremely high development costs and the low economic return generated from each barrel of secondary oil were the main reasons for developing the floods on a multiple-sand basis. The gravel-flow-packed, slotted-liner completion has been a key factor leading to the success of waterflooding in these thick, unconsolidated, multiple-sand reservoirs. The gravel flow pack provides the sand control needed to economically handle the high-rate, high-cut production arising from the unfavorable mobility ratios typical of California waterflood projects. All injection and response wells drilled projects. All injection and response wells drilled after mid-1966 in the offshore field have the gravel-flow-pack completion. The gravel-flow-packed injector wells have excellent injectivity characteristics, and generally have good injection profiles. However, they have one disadvantage in that many of the normal method such as the selective shut-off, used to control the distribution of injection water in other types of completions, cannot be easily applied to the flow pack. Some of the earlier gun-perforated injectors pack. Some of the earlier gun-perforated injectors completed before mid-1966 are still active in the Lower Jones flood. Others have been replaced with the more effective gravel-flow-packed, slotted-liner completion. Routine down-hole surveying of injector wells to check for profile changes with time has been the principal mechanism for monitoring flood principal mechanism for monitoring flood performance. The continuous spinner survey, the performance. The continuous spinner survey, the radioactive-tracer survey, and the continuous temperature survey are combined to generate this vital information. Maintaining desirable profiles is essential if multi-layered waterflooding is to be successful. Pressure fall-off testing and variable-rate testing in water injection wells are additional methods of monitoring flood performance and appraising wellbore damage. performance and appraising wellbore damage.

JPT

P. 1083