Natural fractures and their relationship to the EGS Collab Project in the underground of the Sanford Underground Research Facility (SURF)

EGS Collab Team

Research output: Contribution to conferencePaper

3 Citations (Scopus)

Abstract

The EGS Collab Project (Enhanced Geothermal Systems) is conducting experiments on creating a 10-m scale reservoir and performing non-isothermal fluid circulation tests to assess heat transfer from the rock. The work is being performed in the Poorman Fm., a phyllite exposed on the 4850 Level (1.5 km below the surface) of the Sanford Underground Research Facility (SURF) in northwestern South Dakota. The current phase of the project involves drilling eight closely spaced 60 m long, horizontal holes that are drilled over a range of 69 m along a portion of a drift, a horizontal passageway, on that level. The injection and production holes are drilled 10 meters apart in the direction of the minimum principal stress. Pre-existing natural fractures encountered during drilling appear to be sparse and highly discontinuous and may serve to arrest hydraulic fracture growth, or shear if orientated in critical orientations to the in situ stresses. The general trend of the fracture systems is toward the northwest and is roughly parallel to nearby rhyolite dikes to the northeast. Widely spaced seepage zones intersect the drift near the experiment and in core it is expressed as a 3 m wide zone of partially healed breccia with both open fractures containing calcite crystals and vuggy porosity. Hydro-structural modeling using Golder Associates’ FracMan code shows that the seepage zone largely disappears about 50 m from the drift wall. Pressure build-up tests in nearby boreholes show that the systems appear to have their greatest permeability vertically and often do not connect laterally.

Original languageEnglish (US)
StatePublished - Jan 1 2018
Event52nd U.S. Rock Mechanics/Geomechanics Symposium - Seattle, United States
Duration: Jun 17 2018Jun 20 2018

Other

Other52nd U.S. Rock Mechanics/Geomechanics Symposium
CountryUnited States
CitySeattle
Period6/17/186/20/18

Fingerprint

research facilities
seepage
Seepage
drilling
Drilling
phyllite
passageways
in situ stress
rhyolite
breccia
Levees
heat transfer
Calcium Carbonate
dike
rock intrusions
calcite
borehole
boreholes
experiment
Boreholes

All Science Journal Classification (ASJC) codes

  • Geophysics
  • Geochemistry and Petrology

Cite this

EGS Collab Team (2018). Natural fractures and their relationship to the EGS Collab Project in the underground of the Sanford Underground Research Facility (SURF). Paper presented at 52nd U.S. Rock Mechanics/Geomechanics Symposium, Seattle, United States.
EGS Collab Team. / Natural fractures and their relationship to the EGS Collab Project in the underground of the Sanford Underground Research Facility (SURF). Paper presented at 52nd U.S. Rock Mechanics/Geomechanics Symposium, Seattle, United States.
@conference{a9b68fb46ff34ef9ac4bd7cffcb68474,
title = "Natural fractures and their relationship to the EGS Collab Project in the underground of the Sanford Underground Research Facility (SURF)",
abstract = "The EGS Collab Project (Enhanced Geothermal Systems) is conducting experiments on creating a 10-m scale reservoir and performing non-isothermal fluid circulation tests to assess heat transfer from the rock. The work is being performed in the Poorman Fm., a phyllite exposed on the 4850 Level (1.5 km below the surface) of the Sanford Underground Research Facility (SURF) in northwestern South Dakota. The current phase of the project involves drilling eight closely spaced 60 m long, horizontal holes that are drilled over a range of 69 m along a portion of a drift, a horizontal passageway, on that level. The injection and production holes are drilled 10 meters apart in the direction of the minimum principal stress. Pre-existing natural fractures encountered during drilling appear to be sparse and highly discontinuous and may serve to arrest hydraulic fracture growth, or shear if orientated in critical orientations to the in situ stresses. The general trend of the fracture systems is toward the northwest and is roughly parallel to nearby rhyolite dikes to the northeast. Widely spaced seepage zones intersect the drift near the experiment and in core it is expressed as a 3 m wide zone of partially healed breccia with both open fractures containing calcite crystals and vuggy porosity. Hydro-structural modeling using Golder Associates’ FracMan code shows that the seepage zone largely disappears about 50 m from the drift wall. Pressure build-up tests in nearby boreholes show that the systems appear to have their greatest permeability vertically and often do not connect laterally.",
author = "{EGS Collab Team} and Roggenthen, {W. M.} and Doe, {T. W.} and J. Ajo-Franklin and Bauer, {S. J.} and T. Baumgartner and K. Beckers and D. Blankenship and A. Bonneville and L. Boyd and Brown, {S. T.} and Burghardt, {J. A.} and T. Chen and Y. Chen and K. Condon and Cook, {P. J.} and Dobson, {P. F.} and T. Doe and Doughty, {C. A.} and Derek Elsworth and J. Feldman and A. Foris and Frash, {L. P.} and Z. Frone and P. Fu and K. Gao and A. Ghassemi and H. Gudmundsdottir and Y. Guglielmi and G. Guthrie and B. Haimson and A. Hawkins and J. Heise and Herrick, {C. G.} and M. Horn and Horne, {R. N.} and J. Horner and M. Hu and H. Huang and L. Huang and K. Im and M. Ingraham and Johnson, {T. C.} and B. Johnston and S. Karra and K. Kim and King, {D. K.} and T. Kneafsey and H. Knox and J. Knox and Marone, {Chris J.}",
year = "2018",
month = "1",
day = "1",
language = "English (US)",
note = "52nd U.S. Rock Mechanics/Geomechanics Symposium ; Conference date: 17-06-2018 Through 20-06-2018",

}

EGS Collab Team 2018, 'Natural fractures and their relationship to the EGS Collab Project in the underground of the Sanford Underground Research Facility (SURF)' Paper presented at 52nd U.S. Rock Mechanics/Geomechanics Symposium, Seattle, United States, 6/17/18 - 6/20/18, .

Natural fractures and their relationship to the EGS Collab Project in the underground of the Sanford Underground Research Facility (SURF). / EGS Collab Team.

2018. Paper presented at 52nd U.S. Rock Mechanics/Geomechanics Symposium, Seattle, United States.

Research output: Contribution to conferencePaper

TY - CONF

T1 - Natural fractures and their relationship to the EGS Collab Project in the underground of the Sanford Underground Research Facility (SURF)

AU - EGS Collab Team

AU - Roggenthen, W. M.

AU - Doe, T. W.

AU - Ajo-Franklin, J.

AU - Bauer, S. J.

AU - Baumgartner, T.

AU - Beckers, K.

AU - Blankenship, D.

AU - Bonneville, A.

AU - Boyd, L.

AU - Brown, S. T.

AU - Burghardt, J. A.

AU - Chen, T.

AU - Chen, Y.

AU - Condon, K.

AU - Cook, P. J.

AU - Dobson, P. F.

AU - Doe, T.

AU - Doughty, C. A.

AU - Elsworth, Derek

AU - Feldman, J.

AU - Foris, A.

AU - Frash, L. P.

AU - Frone, Z.

AU - Fu, P.

AU - Gao, K.

AU - Ghassemi, A.

AU - Gudmundsdottir, H.

AU - Guglielmi, Y.

AU - Guthrie, G.

AU - Haimson, B.

AU - Hawkins, A.

AU - Heise, J.

AU - Herrick, C. G.

AU - Horn, M.

AU - Horne, R. N.

AU - Horner, J.

AU - Hu, M.

AU - Huang, H.

AU - Huang, L.

AU - Im, K.

AU - Ingraham, M.

AU - Johnson, T. C.

AU - Johnston, B.

AU - Karra, S.

AU - Kim, K.

AU - King, D. K.

AU - Kneafsey, T.

AU - Knox, H.

AU - Knox, J.

AU - Marone, Chris J.

PY - 2018/1/1

Y1 - 2018/1/1

N2 - The EGS Collab Project (Enhanced Geothermal Systems) is conducting experiments on creating a 10-m scale reservoir and performing non-isothermal fluid circulation tests to assess heat transfer from the rock. The work is being performed in the Poorman Fm., a phyllite exposed on the 4850 Level (1.5 km below the surface) of the Sanford Underground Research Facility (SURF) in northwestern South Dakota. The current phase of the project involves drilling eight closely spaced 60 m long, horizontal holes that are drilled over a range of 69 m along a portion of a drift, a horizontal passageway, on that level. The injection and production holes are drilled 10 meters apart in the direction of the minimum principal stress. Pre-existing natural fractures encountered during drilling appear to be sparse and highly discontinuous and may serve to arrest hydraulic fracture growth, or shear if orientated in critical orientations to the in situ stresses. The general trend of the fracture systems is toward the northwest and is roughly parallel to nearby rhyolite dikes to the northeast. Widely spaced seepage zones intersect the drift near the experiment and in core it is expressed as a 3 m wide zone of partially healed breccia with both open fractures containing calcite crystals and vuggy porosity. Hydro-structural modeling using Golder Associates’ FracMan code shows that the seepage zone largely disappears about 50 m from the drift wall. Pressure build-up tests in nearby boreholes show that the systems appear to have their greatest permeability vertically and often do not connect laterally.

AB - The EGS Collab Project (Enhanced Geothermal Systems) is conducting experiments on creating a 10-m scale reservoir and performing non-isothermal fluid circulation tests to assess heat transfer from the rock. The work is being performed in the Poorman Fm., a phyllite exposed on the 4850 Level (1.5 km below the surface) of the Sanford Underground Research Facility (SURF) in northwestern South Dakota. The current phase of the project involves drilling eight closely spaced 60 m long, horizontal holes that are drilled over a range of 69 m along a portion of a drift, a horizontal passageway, on that level. The injection and production holes are drilled 10 meters apart in the direction of the minimum principal stress. Pre-existing natural fractures encountered during drilling appear to be sparse and highly discontinuous and may serve to arrest hydraulic fracture growth, or shear if orientated in critical orientations to the in situ stresses. The general trend of the fracture systems is toward the northwest and is roughly parallel to nearby rhyolite dikes to the northeast. Widely spaced seepage zones intersect the drift near the experiment and in core it is expressed as a 3 m wide zone of partially healed breccia with both open fractures containing calcite crystals and vuggy porosity. Hydro-structural modeling using Golder Associates’ FracMan code shows that the seepage zone largely disappears about 50 m from the drift wall. Pressure build-up tests in nearby boreholes show that the systems appear to have their greatest permeability vertically and often do not connect laterally.

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UR - http://www.scopus.com/inward/citedby.url?scp=85053464432&partnerID=8YFLogxK

M3 - Paper

ER -

EGS Collab Team. Natural fractures and their relationship to the EGS Collab Project in the underground of the Sanford Underground Research Facility (SURF). 2018. Paper presented at 52nd U.S. Rock Mechanics/Geomechanics Symposium, Seattle, United States.