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SHAPE

Overview

Overview of SHAPE

This website summarizes the results from the SHAPE (Improved methods for measuring SHAle PEremeability) project, which was a joint industry project (JIP) undertaken by the University of Leeds, and sponsored by Chevron, EBN and NEXEN.
The initial aim of the SHAPE project is to developed new methods to measure the permeability of shales. However, a literature review conducted at the start of the project combined with a stear from sponsors has meant that these aims have been expanded to include: measuring other flow mechanisms (e.g. Knusden Diffusion), investigating methods to analyze porosity; and (iii) create a web-based "Atlas of Shale Properties".

 

Analysis undertaken

The SHAPE project is conducting standard measurements to characterize the shale samples provided as well as developing new tests to measure flow properties. Standard characterization being conducted includes:-

  • SEM analysis of the microstructure of shale samples; the samples are being polised using a broad ion beam so that a large volume can be sampled.
  • Mineralogy usign QXRD.
  • Total organic matter content
  • Rock Eval pyrolysis
  • Hg-injection analysis
  • Whole core porosity
  • Crushed shale porosity (as received as well as following cleaning using a range of methods)
  • Crushed shale “permeability” using the GRI method
  • Thermogravimetric analysis

New methods being explored include:

  • Transient flow in thick-walled cylinders
  • Transient flow into full core plugs
  • Pulse decay with upstream and downstream volumes/transducers
  • Pulse decay with only upstream transducer and volume
  • Steady-state permeability with low flow rates measured using PIV.

Numerical modelling

A literature review conducted as part of the SHAPE project identified that gas flow in shales is likely occur by a range of mechanisms including: Knusden diffusion, transitional flow, slip flow and Darcy flow. It was also apparent that care needs to be taken using helium gas to measure flow properties has it has a different mean free path to methane. So it maybe necessary to use methane to measure gas flow in shales. However, methane can be strongly absorped to organic matter during the experiments. It was therefore apparent that we needed to create a numerical model for gas flow in shales that accurately accounted for the different gas flow mechanisms as well as methane adsorption/desorption.
Two models were created based on the work of Civan et al. (2012) that met these criteria. The first uses the control volume method. The second uses the finite element method. The models have both been tested and give the same results. A description of the FE model is given here. The description of the control volume method is current being written up.

 

Deliverables

The key deliverables from SHAPE include:

  • Literature review critically appraising current methods for measuring the porosity and flow properties of shales.
  • Report on the numerical methods developed during the project to invert test results.
  • Report outlining methodologies tested during the current project to measure the porosity and flow properties of shales
  • A web-based atlas on the properties of the shales analyzed during the SHAPE project