Acoustic emission characterization of microcracking in laboratory-scale hydraulic fracturing tests
Understanding microcracking near coalesced fracture generation is critically important for hydrocarbon and geothermal reservoir characterization as well as damage evaluation in civil engineering structures. Dense and sometimes random microcracking near coalesced fracture formation alters the mechanical properties of the nearby virgin material. Individual microcrack characterization is also significant in quantifying the material changes near the fracture faces (i.e. damage). Acoustic emission (AE) monitoring and analysis provide unique information regarding the microcracking process temporally, and information concerning the source characterization of individual microcracks can be extracted. In this context, laboratory hydraulic fracture tests were carried out while monitoring the AEs from several piezoelectric transducers. In-depth post-processing of the AE event data was performed for the purpose of understanding the individual source mechanisms. Several source characterization techniques including moment tensor inversion, event parametric analysis, and volumetric deformation analysis were adopted. Post-test fracture characterization through coring, slicing and micro-computed tomographic imaging was performed to determine the coalesced fracture location and structure. Distinct differences in fracture characteristics were found spatially in relation to the openhole injection interval. Individual microcrack AE analysis showed substantial energy reduction emanating spatially from the injection interval. Lastly, it was quantitatively observed that the recorded AE signals provided sufficient information to generalize the damage radiating spatially away from the injection wellbore.
- Research Organization:
- Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
- Sponsoring Organization:
- USDOE Laboratory Directed Research and Development (LDRD) Program
- Grant/Contract Number:
- FE0002760; AC52-06NA25396
- OSTI ID:
- 1694226
- Alternate ID(s):
- OSTI ID: 1454998
- Report Number(s):
- LA-UR-17-30661; S1674775517304468; PII: S1674775517304468
- Journal Information:
- Journal of Rock Mechanics and Geotechnical Engineering, Journal Name: Journal of Rock Mechanics and Geotechnical Engineering Vol. 10 Journal Issue: 5; ISSN 1674-7755
- Publisher:
- ElsevierCopyright Statement
- Country of Publication:
- China
- Language:
- English
Web of Science
Slip and instability mechanisms of coal‐rock parting‐coal structure (
|
journal | August 2019 |
Microcrack Damage Observations near Coalesced Fractures Using Acoustic Emission
|
journal | April 2019 |
Predictions of macro-scale fracture geometries from acoustic emission point cloud data in a hydraulic fracturing experiment
|
journal | September 2018 |
Experimental Study of Fracturing Fluid Retention in Rough Fractures
|
journal | April 2019 |
Similar Records
Small Scale Field Test Demonstrating CO2 Sequestration In Arbuckle Saline Aquifer And By CO2-Eor At Wellington Field, Sumner County, Kansas
The in-situ TEM observation of microcrack nucleation in titanium aluminide