Using BIB-SEM Imaging for Permeability Prediction in Heterogeneous Shales
C. J. A. Sinn,
J. Klaver,
R. Fink,
M. Jiang,
J. Schmatz,
R. Littke,
J. L. Urai
Affiliations
C. J. A. Sinn
Structural Geology, Tectonics and Geomechanics (GED), Energy and Mineral Resources Group (EMR), RWTH Aachen University, Lochnerstrasse 4-20, 52056 Aachen, Germany
J. Klaver
MaP-Microstructure and Pores GmbH, Lochnerstrasse 4-20, 52064 Aachen, Germany
R. Fink
Institute of Geology and Geochemistry of Petroleum and Coal (LEK), Energy and Mineral Resources Group (EMR), RWTH Aachen University, Lochnerstrasse 4-20, 52056 Aachen, Germany
M. Jiang
MaP-Microstructure and Pores GmbH, Lochnerstrasse 4-20, 52064 Aachen, Germany
J. Schmatz
MaP-Microstructure and Pores GmbH, Lochnerstrasse 4-20, 52064 Aachen, Germany
R. Littke
Institute of Geology and Geochemistry of Petroleum and Coal (LEK), Energy and Mineral Resources Group (EMR), RWTH Aachen University, Lochnerstrasse 4-20, 52056 Aachen, Germany
J. L. Urai
Structural Geology, Tectonics and Geomechanics (GED), Energy and Mineral Resources Group (EMR), RWTH Aachen University, Lochnerstrasse 4-20, 52056 Aachen, Germany
Organic-rich shale samples from a lacustrine sedimentary sequence of the Newark Basin (New Jersey, USA) are investigated by combining Broad Ion Beam polishing with Scanning Electron Microscopy (BIB-SEM). We model permeability from this 2D data and compare our results with measured petrophysical properties. Three samples with total organic carbon (TOC) contents ranging from 0.7% to 2.9% and permeabilities ranging from 4 to 160 nD are selected. Pore space is imaged at high resolution (at 20,000x magnification) and segmented from representative BIB-SEM maps. Modeled permeabilities, derived using the capillary tube model (CTM) on segmented pores, range from 2.3 nD to 310 nD and are relatively close to measured intrinsic permeabilities. SEM-visible porosities range from 0.1% to 1.8% increasing with TOC, in agreement with our measurements. The CTM predicts permeability correctly within one order of magnitude. The results of this work demonstrate the potential of 2D BIB-SEM for calculating transport properties of heterogeneous shales.
