Rates of subcritical cracking and long-term rock erosion

Eppes, M. C.; Hancock, G. S.; Chen, X.; Arey, J.; Dewers, T.; Huettenmoser, J.; Kiessling, S.; Moser, F.; Tannu, N.; Weiserbs, B.; Whitten, J.

doi:10.1130/G45256.1

Title: Rates of subcritical cracking and long-term rock erosion

Abstract

Bedrock fracture is a key element of rock erosion and subsequent surface processes. We test the hypothesis that rock's susceptibility to subcritical cracking, a specific type of fracturing, significantly drives and limits rock erosion. We measured ¹⁰Be-derived erosion rates, compressive strength, and crack characteristics on 20 outcrops of different rock units (quartzite, granite, and two metasandstones) in the northern Blue Ridge Mountains of Virginia (USA). We also measured the subcritical cracking index (n), Charles’s law velocity constant (A), and fracture toughness (K_IC) of samples from four of the same outcrops, representative of each rock type. Erosion rates range from 1.16 ± 0.67 to 32.3 ± 7.8 m/m.y. We find strong correlations—across the four rock units—between average erosion rates and the three subcritical cracking parameters (R² > 0.85, p < 0.05), but not compressive strength (R² = 0.6; p > 0.1). We also find a correlative relationship between n and outcrop fracture length (R² = 0.91; p < 0.05). The latter correlation is consistent with that of published model predictions, further indicating a mechanistic link between subcritical cracking and rock erosion. We infer that subcritical cracking parameters closely tie to erosion rates, because subcritical cracking is the dominant process of mechanicalmore »« less

Authors:

Eppes, M. C. ^[1]; Hancock, G. S. ^[2]; Chen, X. ^[3]; Arey, J. ^[1]; Dewers, T. ^[4]; Huettenmoser, J. ^[2]; Kiessling, S. ^[1]; Moser, F. ^[1]; Tannu, N. ^[1]; Weiserbs, B. ^[1]; Whitten, J. ^[2]

Univ. of North Carolina, Charlotte, NC (United States). Dept. of Geography and Earth Sciences
College of William and Mary, Williamsburg, VA (United States). Dept. of Geology
Univ. of Texas, Austin, TX (United States). Bureau of Economic Geology
Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

Publication Date:: Tue Sep 25 00:00:00 EDT 2018

Research Org.:: Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Univ. of Texas, Austin, TX (United States); Univ. of North Carolina, Charlotte, NC (United States); College of William and Mary, Williamsburg, VA (United States)

Sponsoring Org.:: USDOE Office of Science (SC), Basic Energy Sciences (BES); USDOE National Nuclear Security Administration (NNSA); USDOE Office of Fossil Energy (FE); United States Geological Survey (USGS); Univ. of North Carolina, Charlotte (United States); College of William and Mary (United States)

OSTI Identifier:: 1477884

Report Number(s):: SAND-2018-9306J
Journal ID: ISSN 0091-7613; 667314

Grant/Contract Number:: NA0003525; SC0006883; FE0023316

Resource Type:: Accepted Manuscript

Journal Name:: Geology

Additional Journal Information:: Journal Volume: 46; Journal Issue: 11; Journal ID: ISSN 0091-7613

Publisher:: Geological Society of America

Country of Publication:: United States

Language:: English

Subject:: 58 GEOSCIENCES

Citation Formats


                    Eppes, M. C., Hancock, G. S., Chen, X., Arey, J., Dewers, T., Huettenmoser, J., Kiessling, S., Moser, F., Tannu, N., Weiserbs, B., and Whitten, J. Rates of subcritical cracking and long-term rock erosion.  United States: N. p., 2018. 
Web.  doi:10.1130/G45256.1.

Copy to clipboard


                    Eppes, M. C., Hancock, G. S., Chen, X., Arey, J., Dewers, T., Huettenmoser, J., Kiessling, S., Moser, F., Tannu, N., Weiserbs, B., & Whitten, J. Rates of subcritical cracking and long-term rock erosion.  United States.  https://doi.org/10.1130/G45256.1

Copy to clipboard


                    Eppes, M. C., Hancock, G. S., Chen, X., Arey, J., Dewers, T., Huettenmoser, J., Kiessling, S., Moser, F., Tannu, N., Weiserbs, B., and Whitten, J. Tue .  
"Rates of subcritical cracking and long-term rock erosion".  United States.  https://doi.org/10.1130/G45256.1.  https://www.osti.gov/servlets/purl/1477884.

Copy to clipboard


                    
@article{osti_1477884,

  title        = {Rates of subcritical cracking and long-term rock erosion},

  author       = {Eppes, M. C. and Hancock, G. S. and Chen, X. and Arey, J. and Dewers, T. and Huettenmoser, J. and Kiessling, S. and Moser, F. and Tannu, N. and Weiserbs, B. and Whitten, J.},

  abstractNote = {Bedrock fracture is a key element of rock erosion and subsequent surface processes. We test the hypothesis that rock's susceptibility to subcritical cracking, a specific type of fracturing, significantly drives and limits rock erosion. We measured 10Be-derived erosion rates, compressive strength, and crack characteristics on 20 outcrops of different rock units (quartzite, granite, and two metasandstones) in the northern Blue Ridge Mountains of Virginia (USA). We also measured the subcritical cracking index (n), Charles’s law velocity constant (A), and fracture toughness (KIC) of samples from four of the same outcrops, representative of each rock type. Erosion rates range from 1.16 ± 0.67 to 32.3 ± 7.8 m/m.y. We find strong correlations—across the four rock units—between average erosion rates and the three subcritical cracking parameters (R2 > 0.85, p < 0.05), but not compressive strength (R2 = 0.6; p > 0.1). We also find a correlative relationship between n and outcrop fracture length (R2 = 0.91; p < 0.05). The latter correlation is consistent with that of published model predictions, further indicating a mechanistic link between subcritical cracking and rock erosion. We infer that subcritical cracking parameters closely tie to erosion rates, because subcritical cracking is the dominant process of mechanical weathering, leading to positive feedbacks relating subcritical cracking rates, crack length, porosity, and water accessibility. Finally, these data are the first that directly test and support the hypothesis that subcritical cracking can set the pace of long-term rock erosion.},

  doi          = {10.1130/G45256.1},

  journal      = {Geology},

  number       = 11,

  volume       = 46,

  place        = {United States},

  year         = {Tue Sep 25 00:00:00 EDT 2018},

  month        = {Tue Sep 25 00:00:00 EDT 2018}

}

Copy to clipboard

Journal Article:

Free Publicly Available Full Text

Accepted Manuscript (DOE)

Publisher's Version of Record

https://doi.org/10.1130/G45256.1

Other availability

Search WorldCat to find libraries that may hold this journal

Citation Metrics:

Cited by: 19 works

Citation information provided by
Web of Science

Save / Share:

Export Metadata

Save to My Library

Works referencing / citing this record:

Relaxation Response of Critically Stressed Macroscale Surficial Rock Sheets
journal, May 2019

Collins, B. D.; Stock, G. M.; Eppes, M. C.
Rock Mechanics and Rock Engineering, Vol. 52, Issue 12
DOI: 10.1007/s00603-019-01832-6

Similar Records in DOE PAGES and OSTI.GOV collections:

Critical dilatant volume of rocks at the onset of tertiary creep

Journal Article Kranz, R L ; Scholz, C H - J. Geophys. Res.; (United States)

During uniaxial compression creep tests at 24/sup 0/C, quartzite and granite specimens were subjected to stresses ranging from 73% to 95% of their uniaxial fracture strengths. Fracture times ranged from 10 to 1.6 x 10/sup 6/xs. Strains both parallel (epsilon/sub z/) and perpendicular (epsilon/sub r/) to the maximum stress direction were recorded continuously in order to compute volumetric strain. Tertiary creep is signified by a continuous increase of strain rate in either direction. The amount of time spent in tertiary creep prior to failure was different for the two rock types. Inelastic volumetric strain at the onset of tertiary creepmore »« less
https://doi.org/10.1029/JB082i030p04893
Rock fracture processes in chemically reactive environments

Conference Eichhubl, Peter

Rock fracture is traditionally viewed as a brittle process involving damage nucleation and growth in a zone ahead of a larger fracture, resulting in fracture propagation once a threshold loading stress is exceeded. It is now increasingly recognized that coupled chemical-mechanical processes influence fracture growth in wide range of subsurface conditions that include igneous, metamorphic, and geothermal systems, and diagenetically reactive sedimentary systems with possible applications to hydrocarbon extraction and CO₂ sequestration. Fracture processes aided or driven by chemical change can affect the onset of fracture, fracture shape and branching characteristics, and fracture network geometry, thus influencing mechanical strength andmore »« less
Full Text Available
Subcritical fracturing of shales under chemically reactive conditions

Conference Chen, Xiaofeng ; Wright, Erick ; Major, Jon R. ; ...

Growth of opening-mode fractures under chemically reactive subsurface conditions is potentially relevant for seal integrity in subsurface CO2 storage and hazardous waste disposal. Using double-torsion load relaxation tests we determine mode-I fracture toughness (KIC), subcritical index (SCI), and the stress-intensity factor vs fracture velocity (K-V) behavior of Marcellus, Woodford, and Mancos shales. Samples are tested under ambient air and aqueous conditions with variable NaCl and KCl concentrations, variable pH, and temperatures of up to 70°C. Under ambient air condition, KIC determined from double torsion tests is 1.3, 0.6, and 1.1 MPa∙m1/2 for Marcellus, Woodford, and Mancos shales, respectively. SCI undermore »« less
Full Text Available
Effect of water on critical and subcritical fracture properties of Woodford shale

Journal Article Chen, Xiaofeng ; Eichhubl, Peter ; Olson, Jon E. - Journal of Geophysical Research. Solid Earth

Subcritical fracture behavior of shales under aqueous conditions is poorly characterized despite increased relevance to oil and gas resource development and seal integrity in waste disposal and subsurface carbon sequestration. In this paper, we measured subcritical fracture properties of Woodford shale in ambient air, dry CO₂ gas, and deionized water by using the double-torsion method. Compared to tests in ambient air, the presence of water reduces fracture toughness by 50%, subcritical index by 77%, and shear modulus by 27% and increases inelastic deformation. Comparison between test specimens coated with a hydrophobic agent and uncoated specimens demonstrates that the interaction ofmore »« less
Cited by 28
https://doi.org/10.1002/2016JB013708

Full Text Available
Quantitative Characterization of Impacts of Coupled Geomechanics and Flow on Safe and Permanent Geological Storage of CO₂ in Fractured Aquifers

Technical Report Winterfeld, Philip ; Wu, Yu-Shu ; Kneafsey, Timothy

This is the final scientific report for the award DE-FE0023305, entitled “Quantitative Characterization of Impacts of Coupled Geomechanics and Flow on Safe and Permanent Geological Storage of CO₂ in Fractured Aquifers.” The work has been divided into six tasks. In Task 2, we characterized rock properties, which are important when developing a quantitative approach for understanding and predicting geomechanical effects on large-scale CO₂ injection and long-term storage in the subsurface. Rock properties of interest for this characterization include porosity, permeability, elastic constants, strength, and heat capacity. We measured rock properties for three different rock types: concrete, sandstone and shale. Thesemore »« less
https://doi.org/10.2172/1487433

Full Text Available

Similar Records

Title: Rates of subcritical cracking and long-term rock erosion

Abstract

Citation Formats

Relaxation Response of Critically Stressed Macroscale Surficial Rock Sheets journal, May 2019

Relaxation Response of Critically Stressed Macroscale Surficial Rock Sheets
journal, May 2019