AAPG Annual Convention and Exhibition

Datapages, Inc.Print this page

Electrical and Acoustic Properties Evaluation of Reconsolidated Mudrocks as a Function of Organic Matter Content

Abstract

Electrical and Acoustic Properties Evaluation of Reconsolidated Mudrocks as a Function of Organic Matter Content. Palencia, Clara1, Dr. Hathon, Lori1, Dr. Myers, Michael1 1 University of Houston, Houston, Texas, United States The objective of this research is to quantify the variation in electrical, acoustic, and strength properties of reconsolidated mudrocks with variable organic matter content. The reconsolidation technique allows us to build fundamental understanding of shale properties by making our own mudrocks under controlled conditions. A slurry of known particle size, mineralogy, Total Organic Carbon (TOC), Cation Exchange Capacity (CEC), water content (initial porosity) and pore fluid salinity is compacted in an odometer cell. The advantage of this technique is that these initial features can be modified one at a time, such that the impact of individual variables can be analyzed. By applying an axial load and measuring axial strain, porosity and permeability can be readily calculated from the compaction test results. Fluid expulsion can be monitored, and expelled fluid chemistry properties (the conductivity and the ionic composition) can be measured. TOC and pore fluid salinity have been of particular interest in this study. Both of these parameters have been varied leaving all the others constant. Once the sample is reconsolidated, a one by two inch core plug is produced that is imaged with micro CT. Physical property measurements, including porosity, permeability, NMR T2 spectra, acoustic and electric properties, will be related to the TOC and salinity changes. Imaging in thin section and in SEM, together with image analysis will be used to document pore, mineral, and organic phase distribution, orientation and relative connectivity, and how these parameters influence the physical property measurements. The ultimate goal of this work is to build a saturation model for log analysis and interpretation in unconventional reservoirs.