Lloydminster Area Research Articles

Abstract "Formation evaluation" comprises correlation, reservoir detection andreservoir evaluation. In the Chauvin, Wainwright and Lloydminster areas, theprincipal heavy oil reservoir is the Sparky sand. The oil sand pools are surrounded by halos or "channels" of shale. Correlation is more difficult inthe Lloydminster area than in the Wainwright area or the Chauvin area becausethe sand distribution is more complex. Reservoir detection is more difficult at Wainwright and Chauvin because the oil sands are thin and apparent resistivities are low; at Lloydminster, the oil sands are thick and apparent resistivities are high. At Wainwright and Chauvin, a resistivity log, aporosity log and often a drill stem test are necessary for a decision to set pipe; at Lloydminster, all that is required is an electrical log. Productivity varies considerably from pool to pool, probably because of changes in sand permeability and oil viscosity. As these changes cannot be detected by the electrical log prior to setting pipe, the present practice is to determine productivity by production testing after setting, pipe. Transmissibility(kh)/u, as derived from drill stem test data, may provide a means of estimating productivity prior to setting pipe. Introduction The techniques used for formation evaluation vary from area to area, as each area has problems which are peculiar to it. The purpose of this paper is to discuss some of the problems peculiar to the heavy oil reservoirs of the Lloydminster, Chauvin and Wainwright areas, and to mention certain techniques which provide the necessary data simply and economically. In the following, the Lloydminster area will be discussed first; this will be followed by adiscussion of the Wainwright and Chauvin areas. The geology of each area willbe commented on, but only insofar as it bears on the problem of correlation andreservoir identification.