Previous Talks

Wednesday, March 13th, 2013

A New Petrophysical Model for Organic Shales and Rock Physics Applications

Dicman Alfred and Lev Vernik, Marathon Oil Corporation


Unconventional shale reservoirs have gained significant importance in the recent years in terms of reserves and production perspective. The formation evaluation aspect of these reservoirs is still in the phase of continuous evolvement. There are several petrophysical models that have been proposed for the shale plays ranging from volumetric solutions by reproducing the measured logs to applying conventional techniques like Archie, Simandoux, etc. In this paper we propose a new physically consistent solution based on partitioning the system into kerogen and non-kerogen domains with their associated porosities. These domains are not simply an arbitrary construct: they are directly suggested by the nano-scale images that have been acquired for these shale plays. The new model follows an approach that have been used in the past for understanding other systems in which there is a heterogeneity at a scale significantly finer than the measurements . The model is based on the premise that the hydrocarbon phase occupies the kerogen-related porosity with water occupying the non-kerogen matrix porosity thereby eliminating the need to compute saturations using conventional methods. The innovative aspect to this approach is that the new model solves for the kerogen porosity created by the organic diagenesis and constrained by physically meaningful bounds. The model also successfully explains industry standard approach such as Schmoker’s equation. The talk will also feature the rock physics applications currently pursued at Marathon in unconventional resources.

Speaker Biography

Dicman Alfred is a Senior Petrophysicist of the Upstream Technology Worldwide Petrophysics group for Marathon Oil. He holds a Master Degree in Petroleum Engineering from Texas A&M and a Bachelor’s Degree in Mechanical Engineering from Indian Institute of Technology, Madras. Currently he leads the integrated reservoir characterization studies for one of Marathon’s North American assets. Prior to his current position he was involved in the reservoir evaluation/completion optimization of shale plays using log data and petrophysical seismic inversion of unconventional/conventional reservoirs. Prior to joining Marathon, he worked as a wireline field engineer for Halliburton Energy Services and as a Petroleum Engineer for Schlumberger Information Solutions.

Lev Vernik is a Senior Technical Consultant working in Worldwide Geosciences group, Upsteam Technology, Marathon Oil. He holds a PhD Degree in Geophysics (Rock Physics) from All-Union Geosciences Institute, St. Petersburg, Russia. His current responsibilities include rock physics-based seismic AVO modeling and analysis worldwide for prospect derisking and seismic reservoir characterization. Prior to joining Marathon he worked in petrophysics and geophysics positions with ARCO, Vastar, BP, and Noble Energy. Prior to joining the oil and gas industry he conducted research at the Geophysics Department of Stanford University and Kola Superdeep Drilling project in the former Soviet Union.