Logging under Harsh Conditions with New Shuttle-Deployed Memory Tools and Impact on Log Quality, Time and Costs

Abstract

Abstract Operational conditions in certain fields can cause various difficulties during logging operations. When such situations occur, we usually opt for logging-while-drilling (LWD) tools. In this paper, we present field applications and advantages of a new generation of tools called shuttle-deployed memory (SDM) tools. Because they can operate under critical borehole conditions and highly deviated wells, SDM tools offer a viable alternative to LWD. We successfully applied this technology to acquire well-log data in two fields of clastic and carbonate reservoirs in the Barinas-Apure Basin, Southwest Venezuela. In this area, conditioning the hole is a required procedure before running logging tools; therefore, the logging system's capacity to get information while conditioning the borehole favored its application when logging under harsh conditions. We show three cases considering wells with angle of deviation up to 40º, dog leg severity up to 4º/100 ft, and several washout and unsteady zones. A comparison with resistivity measurements obtained using an LWD tool is also included in one of the cases, illustrating remarkable improvements in log quality. We also used the acquired information as an input for petrophysical assessment. The results satisfactorily compared against neighbor wells with data obtained from conventional wireline logging tools and rock-core measurements. Likewise, a detailed analysis of time and cost describes the impact of the application of this type of technology on operations in Guafita and La Victoria Fields in Venezuela. We conclusively found that the application of SDM tools for formation evaluation data acquisition reduces logging time by 62% and logging costs up to 44% in these fields. In addition, we obtained reliable well-log information with significant improvements in log quality. More important, the application of SDM tools allowed us to bypass the limitations in terms of variety and quantity for logs that were commonly acquired with LWD tools.