Chattering Dust to Map Fracture Flow Path Topology and Geometry
Abstract
Passive micro-seismic geophysical approaches use signals generated by local abrupt failure to monitor the evolution of fracture systems in the Earth's subsurface. Limitations of micro-seismic approaches include: (1) non-selective events can occur anywhere within the subsurface system, away from fractures of interest; (2) aseismic events may provide no measurable signal of fracture evolution; and (3) interpretation of events provide little or no information on fracture connectivity. Here we present a novel approach that overcomes these limitations by using transportable time-release micro-seismic granules known as "chattering dust" to map fracture flow paths. The chattering dust encapsulates compressed gasbubbles that burst concussively as the dust is chemically eroded. Unlike MEMs-based devices, the deformability of chattering dust enables them to pass through narrow constrictions in a fracture or fracture network.
In this study, we demonstrate the use of chattering dust to assess relative apertures of uniform aperture fractures under gravitational settling, to track flow paths in intersecting fracture networks, and to map fluid currents in non-uniform aperture fractures. This approach combines particle transport and chemically-induced seismicity with wave inversion to advance our ability to characterize fracture systems in the laboratory and in the subsurface. Acknowledgment: This material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Geosciences Research Program under Award Number (DE-FG02-09ER16022).- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFMNG12A..08P
- Keywords:
-
- 3336 Numerical approximations and analyses;
- ATMOSPHERIC PROCESSES;
- 1990 Uncertainty;
- INFORMATICS;
- 4440 Fractals and multifractals;
- NONLINEAR GEOPHYSICS;
- 8010 Fractures and faults;
- STRUCTURAL GEOLOGY