New LWD Slimhole Imaging Technology Applications for Completion System Optimization in Naturally Fractured Carbonate Reservoirs in Mexico
Open-hole completion with inflow control devices (ICDs) was implemented
in the most recent horizontal wells in the Cantarell field to improve well
performance and enhance reservoir management by mitigating undesired water or
gas breakthroughs. The approach taken by PEMEX consists of reducing drawdown in
high-permeability sections to allow more oil to flow from lower-productivity
sections and isolating highly fractured zones that could be connected to an
aquifer. Success of the completions with ICDs relies heavily on an accurate
Borehole images are used for fracture identification and quantification
in the horizontal section. Fracture analysis is used to identify and isolate
highly fractured zones and estimate permeability along the horizontal section.
Wireline borehole imaging tools were used for the first horizontal wells in the
Cantarell field to provide this essential information. A horizontal well is a
challenging environment for data acquisition with wireline logging tools
because they require drill pipe conveyed or a wireline tractor system. There
are many cases where wireline tools were not able to reach total depth due to
borehole conditions, thus leaving horizontal section without acquiring
necessary information for ICDs completion design.
In order to assure the information needed, there are new technologies
that could be used during drilling or in wiper trip mode to record the data
minimizing the risks and optimizing acquisition time. This paper presents a
case study demonstrating the results obtained for two horizontal wells,
Cantarell-490H and Cantarell-470H, using a new LWD slimhole imaging technology.
This provided an opportunity to reduce the risk of data acquisition as well
reducing additional acquisition time. This new generation of measurement
designed for slimhole provides laterolog resistivity and borehole images in 6
inches hole sizes drilled with conductive mud. Borehole resistivity images are
acquired in 56 sectors, providing full borehole coverage.
The resistivity images acquired with the new LWD slimhole imaging
technology enabled the identification of natural and induced fractures, vugs,
and dips. The image interpretation integrated with petrophysical analysis
allowed for optimum placement of the ICDs and openhole packers for the
completion of the wells in this case study.