The Horse Creek Air Injection Project: An Overview

Abstract

Abstract On May 17, 1996 Total Minatome Corporation began high pressure air injection into the Ordovician Red River formation at the Horse Creek Field, Bowman County, North Dakota. The Horse Creek project is the third high pressure air injection program to be implemented into a light oil reservoir in this portion of the Williston Basin. In order to evaluate the enhanced recovery potential of the Horse Creek field, Total Minatome Corporation completed a series of geologic and reservoir studies designed to ensure that the most efficient and cost effective enhanced recovery method was employed. These studies involved a detailed geologic reservoir description. several reservoir simulation studies. and laboratory experiments designed to obtain kinetic parameters required for thermal modeling. This paper presents an overview of the results from these studies and gives the first production information from the project. Introduction On May 17, 1996, Total Minatome Corporation initiated an enhanced recovery high pressure air injection project at the Horse Creek field, Bowman County North Dakota. This project is the third high pressure air injection program completed in the Ordovician Red River formation in the Williston Basin. Prior to the Horse Creek Project, air injection programs were successfully initiated at the Buffalo Red River Unit in Harding County, South Dakota and the Medicine Pole Hills Unit in Bowman County, North Dakota. Both of these projects were initiated by Koch Industries, but are now operated by Continental Resources. The Horse Creek field is located 7 miles to the east of the Cedar Creek anticline, in the south-central portion of the Williston Basin, Bowman County, North Dakota. (Figure No. 1). The field was discovered in, November 1972, and consists of 15 producing oil wells. Total Minatome Corporation began to evaluate the enhanced recovery potential of the field in May, 1993, by conducting geological, laboratory, and reservoir modeling studies on the field. Based upon the encouraging results from these studies, Total Minatome Corporation formed an enhanced recovery unit for the Horse Creek field in, November 1995. Air injection into the reservoir began on May 17, 1996. Total Minatome Corporation currently operates eleven producing wells, three air injection wells, one monitor well, and one water disposal well within the unit area. Presently, air is being injected into the reservoir through three injection wells at a rate of approximately 8,500 MSCF/D at a 4700 psi discharge pressure. Nine months after injection start up, results from the project are encouraging, as the reservoir pressure continues to rise and production has increased from 293 BOPD to 400 BOPD. This paper presents an overview of the geology, reservoir characteristics, reservoir simulation studies, and compression facilities. The paper also presents the first available production data on the project. Reservoir Characterization Geology. The Horse Creek field is a stratigraphic oil accumulation within the Ordovician Red River formation. The field is located in the south-central portion of the Williston Basin, Bowman County, North Dakota (Figure No. 1). The Red River formation, in this portion of the Williston Basin, is subdivided into four porosity zones by industry workers. These porosity zones are referred to as the "A" through "D" zones (Figure No. 2). Air injection at the Horse Creek field has been limited to the "D" porosity zone. P. 143^