|Publisher||Society of Petroleum Engineers||Language||English|
|Content Type||Conference Paper|
|Title||Production Performance Study of West Carney Field, Lincoln County, Oklahoma|
|Authors||Rahul Joshi, Mohan Kelkar, The University of Tulsa|
SPE/DOE Symposium on Improved Oil Recovery, 17-21 April 2004, Tulsa, Oklahoma
|Copyright||2004. Society of Petroleum Engineers|
The paper describes a field case study of Hunton formation in West Carney Field in Oklahoma. The Hunton formation covers 2.7 million acres in Oklahoma and in surrounding states of Texas, New Mexico and Arkansas and is one of the most prolific oil producing reservoirs in Oklahoma. The formation is geologically complex with a large number of fractures. Some of the unique characteristics of the field include decreasing GOR at the beginning of production, increase in GOR after shut-in and sustained oil rates over long periods of time. Fluid properties analysis of data obtained from laboratory tests has indicated that the reservoir fluid is volatile oil. Reservoir fluid model is generated from fluid properties data and is used in simulating the reservoir depletion process.
Production mechanism involved de-watering of the reservoir and production of oil and gas thereafter by solution gas drive. Since the reservoir fluid was observed to be volatile oil, a modified material balance method for depletion of volatile oil reservoirs was developed to calculate the initial in-place reserves and recovery factors.
A single well reservoir model was developed and compositional flow simulation was carried out using GEOQUEST E300 simulator. History matching methods were used to adjust the reservoir parameters to match the field production of both oil and gas wells. Most of the unique characteristics observed in the field could be reproduced using simulation. The model is also used to evaluate different enhanced recovery methods.
The West Carney field is located in Lincoln County, Oklahoma (Figure 1) and produces from the Hunton formation. The formation is a highly heterogeneous fractured carbonate reservoir. Initial production from the field was sporadic. The wells drilled early in the life of the field showed excessive water production and were abandoned due to lack of water disposal and surface facilities. The unique characteristics of the field are:
The objective of this work is to develop a reservoir model and production mechanism that would explain the aforementioned characteristics successfully. This study utilizes the work done by Marwah1 and Ramakrishna2 in developing a reservoir model that is consistent with geological and petrophysical data. The earlier1 model used a gas cap with an oil rim and a high permeability fracture layer. The simulation used a black oil model for reservoir fluid. The model could reproduce oil behavior but was not able to successfully reproduce the gas production profile. The recovery factor calculation was based on the black oil model. It is now known that the reservoir fluid does not follow black oil behavior. This work aims at establishing the nature of reservoir fluid based on the analysis of fluid samples from different wells and incorporating this fluid model in the reservoir simulation. A detailed analysis of fluid samples is done and a procedure for generating the most representative fluid model is developed. This involves selection and regression of equation of state to generate the fluid model that is consistent with laboratory test observations. The model is later used for in performing compositional simulation of the reservoir.
|File Size||390 KB||11|