Integrated Multidisciplinary Workflow for Shale Play Characterization: Towards Selecting Best Landing Points in the Vaca Muerta Formation, Neuquen Basin, Argentina

Abstract

Identification of best landing point in thick shale formation is a top concern regarding technical and economical perspectives. This paper describes a workflow where various specialists working in unconventional shale play with multi scales data are capable to characterize best targets for well placement. Shale resources vary from shale play to shale play; this implies building relationship throughout nanopores to seismic scales data. Several steps along the workflow are required and correspond to three different scales of investigation, from (1) core scale to (2) log scale and finally (3) sedimentary body/seismic scale. Cores are sampled for petrophysical, mineralogical, geochemical and geomechanical analysis. Early integration of such core data within a common process represents the foundation of the workflow. The microscopic and macroscopic sedimentary descriptions together with all available core experiments characterize the input data for a petrophysical synthesis. Creating a log model as discussed in this paper, first consists in a merger between core data and log responses. Wireline log data represent the lone continuous acquisition along the wells. Logs are involved in a complex workflow delivering different kinds of interpretations along the section of interest with complementary targets. Finally, the ultimate step of investigation corresponds to the decametric sedimentary body investigation identified at seismic scale. Facies association model used at that scale provides keys to constrain robust correlation scheme as well as criteria to propose and predict target intervals. This involves understanding sedimentary facies distribution in relation to depositional environment and eventually the relationship between hydrocarbon storage and production represented by the most carbonaceous facies and those ensuring the rigid frame of the reservoir. This innovative project combines the geological understanding of the reservoir and the geomechanicist view. The sedimentary model allows focusing on the best landing points while facies definition helps predicting the quality of the reservoir and its mechanical properties. Given a sequence stratigraphic framework the suite of wireline well logs models and sedimentary facies association models provide at seismic scale a predictable vertical and lateral facies stacking architecture. All together this integrated workflow represents a powerful tool for well placement as well as development plan optimization.

AAPG Datapages/Search and Discovery Article #90291 ©2017 AAPG Annual Convention and Exhibition, Houston, Texas, April 2-5, 2017