SPWLA Webinar May 2018

SPWLA Webinar May 2018
Improved Assessment of Hydrocarbon Saturation in Mixed-Wet Rocks with Complex Pore Structure

Speaker: Artur Posenato Garcia, Ph.D. candidate in the Hildebrand Department of Petroleum and Geosystems Engineering at The University of Texas at Austin

Speaker Bio:

Artur Posenato Garcia is a Ph.D. candidate in the Hildebrand Department of Petroleum and Geosystems Engineering at The University of Texas at Austin. He holds a M.Eng. in Aeronautical and Mechanical Engineering from the Technological Institute of Aeronautics, Brazil. He worked with aeroservoelasticity at Embraer’s executive jets division from 2007 to 2009, as an artificial lift engineer at Petrobras from 2009 to 2014 in Brazil, and as a simulator systems analyst at Aker Solutions/MHWirth from 2014 to 2015 in Norway. He was designated a Distinguished Speaker for 2017/2018 by the Society of Petrophysicists and Well Log Analysts (SPWLA). Artur is currently a graduate research assistant at The University of Texas at Austin. His research interests include Formation Evaluation, Petrophysics, Pore Scale Physics, Petroleum Engineering, and Mathematical Modeling.

Improved Assessment of Hydrocarbon Saturation in Mixed-Wet Rocks with Complex Pore Structure



This work narrows down the knowledge gap in interpretation of electrical resistivity measurements in oil-wet and mixed-wet formations by analytically deriving a new resistivity model that can reliably estimate hydrocarbon reserves at different levels of wettability. The objectives of this work include (a) to quantify the influence of wettability on electrical resistivity measurement, (b) to develop a newanalytical resistivity model that takes into account the impacts of wettability on electrical resistivity, and (c) to improve the assessment of hydrocarbon saturation by introducing a wettability-dependent parameter into a new resistivity method. The new resistivity model not only incorporates wettability of the rock, but also a directionally conducting fractional pore network to honor rock fabric.


The aforementioned features are quantitatively evaluated from the three-dimensional (3D) pore-scale images, taken from each rock type in the formation. We apply a semianalytical streamline numerical model to estimate pore-network connectivity in the 3D binary images. The resistivity and the calculated geometry-related parameters are used as inputs to the new model in order to estimate water saturation. To test the performance of the introduced method at different levels of wettability and water saturation, we synthetically saturate the pore-scale images with water and oil at different wettability configurations and water saturation, honoring the physics of intermolecular interactions between different fluid and solid components.


The results obtained from the new method are compared against the actual saturation. We successfully applied the introduced method to carbonate rock samples with wettability ranging from strongly oil-wet to strongly water-wet. The electrical resistivity results obtained from numerical simulations were in agreement with the resistivity estimates from the new method. The results also showed that wettability has a significant influence on electrical resistivity of the rocks at water saturation levels below 50%. Moreover, we demonstrated that the proposed model provides reliable results when applied to field data. The outcomes of this work are promising for well-log-based applications of the new method in complex mixed-wet formations.

There are two identical sessions, please register for only ONE session which fits your schedule. 

Morning - Wednesday, May 16th,    8am – 9am US Central Time; 
Evening - Thursday, May 17th   8pm – 9pm US Central Time.

This event is free for current members only. Login to your account to register. New Members are welcome by creating a profile and becoming active in the Society. 
(PLEASE NOTE: If you just paid your dues. You can not register for this event until your payment posts the next business day)

5/16/2018 - 5/17/2018

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