SPWLA New Orleans Chapter 2019 Mar 21 Lunch Meeting

SPWLA New Orleans Chapter 2019 Mar 21 Lunch Meeting

SPWLA Monthly Luncheon Meeting  

March 21 2019

PanAm Building- Suite 1600

601 Poydras St,
New Orleans, LA 70130

11:30 – 1:00 pm

Register and pay online or pay cash/check at the door.
: Elizabeth Tanis (
Cost - $25 

Improved Interpretation of Electrical Resistivity Measurements in Mixed-Wet Rocks:
An Experimental Core-Scale Application and Model Verification

Presented By: Chelsea Newgord - The University of Texas at Austin, Petroleum Engineering Master's Student 


Interpretation of electrical resistivity measurements for assessing hydrocarbon saturation in mixed-wet and hydrocarbon-wet rocks often requires extensive recalibrations of resistivity models. In these conventional resistivity models, the impact of wettability is not reliably incorporated. Recently, we analytically derived a new resistivity model that incorporates parameters to account for wettability and complexity of pore structure. This new model requires experimental verification to enhance its applicability in core- and log-scale domains. In this paper we (1) experimentally quantify the influence of wettability on electrical resistivity measurements, (2) improved and verified our analytically derived resistivity model in rocks with different levels of wettability at different water saturations, and (3) demonstrated the physical meaning of the parameters related to wettability in the resistivity model. We altered the wettability of selected core samples from the same rock type. To prepare the core samples as mixed-wet, a surfactant solution was injected into the samples and then they were aged in decane. These approaches created a range of wettability states in the samples. To quantify the altered wettability of the samples, we used the combined USBM and Amott-Harvey method along with sessile drop contact angle measurements. Next, we used a centrifuge to vary the water saturation in the core samples. We then measured the electrical resistivity of each sample. Finally, we improved the recently introduced resistivity model and compared the estimates of resistivity index from the improved model against the experimentally measured resistivity indices.


We successfully verified the reliability of the improved resistivity model for mixed-wet carbonate core samples. The wettability of the core samples was altered to be in the range of 0.1 to 0.4 on the Amott wettability scale. We also demonstrated that all the coefficients required by the improved resistivity model are physically meaningful. One of the unique contributions of this paper is the introduction of a new interpretation diagram, called the wettability triangle. This diagram can potentially be used to quantify wettability from resistivity measurements, if combined with other geophysical measurements. The outcomes of this work are promising for reliable interpretation of resistivity logs in mixed-wet formations for improved assessment of hydrocarbon saturation with minimal calibration efforts.

BIO: Chelsea Newgord is petroleum engineering Master’s student in the Hildebrand Department of Petroleum and Geosystems Engineering at The University of Texas at Austin. Previously, she worked as a reservoir geophysicist at Sigma Cubed Integrated Reservoir Services in Denver from 2012 to 2017. Her work included building reservoir models from seismic and well-log data to identify drilling targets. She graduated in 2012 with a BS degree in geophysical engineering from Colorado School of Mines, with minors in geology and public affairs. She is a current member of SPWLA, SPE, and SEG. Her research interests include core-analysis, petrophysics, and integrated reservoir characterization.


New Orleans Chapter Open Positions: President Elect, Scholarship Committee Chair
Don't forget to renew your SPWLA Membership for 2019!

3/21/2019 11:30 AM - 1:00 PM
601 Poydras St PanAm Building- Suite 1600 New Orleans, LA 70130 UNITED STATES

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