Tectonic History Validation in a Multi-Phase Deformation Basin Using Natural Fracture System, Vaca Muerta Fm., Argentina.

摘要

Tectonic history understanding is a key element in multiple aspects in oil industry. It has a huge impact in Paleogeography and facies distribution, Trap generation, Petroleum System development, etc. There exist several ways of approaching the tectonic history of a particular area, from field studies to more detailed analytical studies like age dating and apatite fission tracks. In the current study a methodology for validating and quantifying the tectonic history analysis using the natural fracture network is applied. This is based in the fact that natural fracture systems enclose the stress orientation and tectonic regime that generated them. Fractures observed in image logs and cores are used as the main input data to characterize the subsurface fracture system. Initially, a tectonic analysis based on seismic interpretation and published information from the basin was made. Several 3D geomechanical models were carried out to cover all the possible combination of events considering a discrete range of stress direction and magnitudes stablished during previous tectonic analysis. At the end, comparing the orientation fitting between subsurface fracture planes and those given by all the different orientation and regime scenarios we could precisely stablish the most probable stress direction and magnitude for each tectonic event.