View source for Frontier Observatory for Research in Geothermal Energy

'''Frontier Observatory for Research in Geothermal Energy (FORGE)''' is a US government program supporting research into [[geothermal energy]].<ref name=":0">{{cite web |author=Geothermal Technologies Office |date=February 21, 2014 |title=DOE Announces Notice of Intent for EGS Observatory |url=http://www1.eere.energy.gov/geothermal/news_detail.html?news_id=21286 |archive-url=https://web.archive.org/web/20150324225912/http://www1.eere.energy.gov/geothermal/news_detail.html?news_id=21286 |archive-date=2015-03-24 |publisher=Department of Energy}}</ref> The FORGE site is near Milford, Utah, funded for up to $140 million. As of 2023, numerous test wells had been drilled, and flux measurements had been conducted, but energy production had not commenced.<ref name=":1" />

== History ==
In February 2014, the [[Department of Energy]] (DOE) announced the intent to establish "a dedicated subsurface laboratory"<ref name=":0" /> to investigate and develop [[enhanced geothermal systems]].<ref>{{cite web |date=Aug 31, 2016 |title=Energy Department Announces $29 Million Investment in Enhanced Geothermal Systems Efforts |url=https://www.energy.gov/articles/energy-department-announces-29-million-investment-enhanced-geothermal-systems-efforts |publisher=Department of Energy |location=Washington, DC}}</ref> In June 2018 DOE funded a location outside of Milford, Utah for up to $140 million.<ref>{{cite web |title=Department of Energy Selects University of Utah Site for $140 Million Geothermal Research and Development |url=https://www.energy.gov/articles/department-energy-selects-university-utah-site-140-million-geothermal-research-and |access-date=9 March 2020 |website=Department of Energy }}</ref>

== Site ==
The site is located along the [[Colorado Plateau]] and [[Basin and Range Province]] transition zone. It is primarily composed of intrusive [[Oligocene]] through [[Miocene]] batholith emplaced into [[Precambrian]] metamorphic ([[Gneiss]]) and [[Paleozoic]] sedimentary rocks.<ref name=":4">{{Cite book |last1=Knudsen |first1=Tyler |title=Geothermal Characteristics of the Roosevelt Hot Springs System and Adjacent FORGE EGS Site, Milford, Utah |last2=Kleber |first2=Emily |last3=Hiscock |first3=Adam |last4=Kirby |first4=Stefan M. |year=2019 |language=en-US |chapter=Quaternary Geology of the Utah FORGE Site and Vicinity, Millard and Beaver Counties, Utah |doi=10.34191/mp-169-b |access-date=2021-11-08 |chapter-url=https://ugspub.nr.utah.gov/publications/misc_pubs/mp-169/mp-169-b.pdf |s2cid=204250666}}</ref><ref name=":5">{{Cite book |last=Kirby M. |first=Stefan |title=Geothermal Characteristics of the Roosevelt Hot Springs System and Adjacent FORGE EGS Site, Milford, Utah |year=2019 |pages=12–19 |language=en-US |chapter=Revised Mapping of Bedrock Geology Adjoining the Utah FORGE Site |doi=10.34191/MP-169-A |access-date=2021-11-08 |chapter-url=https://ugspub.nr.utah.gov/publications/misc_pubs/mp-169/mp-169-a.pdf |s2cid=204256632}}</ref> The site is west of the [[Mineral Mountains (Utah)|Mineral Mountains]] and about two km east of the north–south trending Opal Mond Fault (OMF), perpendicular to the east–west trending Negro Mag Fault (NMF).<ref name=":4" /><ref>{{Cite book |last1=Rahilly |first1=Kristen |title=Geothermal Characteristics of the Roosevelt Hot Springs System and Adjacent FORGE EGS Site, Milford, Utah |last2=Simmons |first2=Stuart |last3=Fischer |first3=Tobias P. |year=2019 |language=en-US |chapter=Carbon Dioxide Flux and Carbon and Helium Isotopic Composition of Soil Gases Across the FORGE Site and Opal Mound Fault, Utah |doi=10.34191/mp-169-i |access-date=2021-11-08 |chapter-url=https://indd.adobe.com/view/96b5e14d-49a0-4247-8314-6aed7e34b953 |s2cid=204269519}}</ref> FORGE is dominated by a fault-fracture mesh system with OMF as one of its most active features.<ref name=":5" /><ref name=":6">{{Cite journal |last1=Moore |first1=Joseph |last2=McLennan |first2=John |last3=Pankow |first3=Kristine |last4=Simmons |first4=Stuart |last5=Podgorney |first5=Robert |last6=Wannamaker |first6=Philip |last7=Jones |first7=Clay |last8=Rickard |first8=William |last9=Xing |first9=Pengju |date=February 10–12, 2020 |title=The Utah Frontier Observatory for Research in Geothermal Energy (FORGE): A Laboratory for Characterizing, Creating and Sustaining Enhanced Geothermal Systems |url=https://pangea.stanford.edu/ERE/db/GeoConf/papers/SGW/2020/Moore.pdf |journal=Workshop on Geothermal Reservoir Engineering Stanford University, Stanford, California |pages=1–10}}</ref> Fault structures vary from steeply dipping faults west of the Mineral Mountains to more gently steeping faults to the east.<ref name=":5" /><ref name=":4" />

The reservoir is located approximately between 1,525 and 2,896 meters (~5,000-10,000&nbsp;ft) depth in which temperature ranges from 175 to 225&nbsp;°C.<ref name="auto">{{Cite journal |last1=Moore |first1=Joseph |last2=McLennan |first2=John |last3=Allis |first3=Rick |last4=Pankow |first4=Kristine |last5=Simmons |first5=Stuart |last6=Podgorney |first6=Robert |last7=Wannamaker |first7=Philip |last8=Bartley |first8=John |last9=Jones |first9=Clay |last10=Rickard |first10=William |title=The Utah Frontier Observatory for Research in Geothermal Energy (FORGE): An International Laboratory for Enhanced Geothermal System Technology Development |url=https://pangea.stanford.edu/ERE/pdf/IGAstandard/SGW/2019/Moore.pdf |journal=Workshop on Geothermal Reservoir Engineering Stanford University, Stanford, California}}</ref> The rock is aged from 8 Ma to 25.4 Ma.<ref name=":7">{{Cite journal |last1=NIELSON |first1=DENNIS L. |last2=EVANS |first2=STANLEY H., JR. |last3=SIBBETT |first3=BRUCE S. |date=1986-06-01 |title=Magmatic, structural, and hydrothermal evolution of the Mineral Mountains intrusive complex, Utah |url=https://doi.org/10.1130/0016-7606(1986)972.0.CO;2 |journal=GSA Bulletin |volume=97 |issue=6 |pages=765–777 |bibcode=1986GSAB...97..765N |doi=10.1130/0016-7606(1986)97<765:MSAHEO>2.0.CO;2 |issn=0016-7606}}</ref><ref>{{Cite journal |last1=Coleman |first1=Drew S. |last2=Walker |first2=J. Douglas |date=1992 |title=Evidence for the generation of juvenile granitic crust during continental extension, Mineral Mountains Batholith, Utah |url=https://onlinelibrary.wiley.com/doi/abs/10.1029/92JB00653 |journal=Journal of Geophysical Research: Solid Earth |language=en |volume=97 |issue=B7 |pages=11011–11024 |bibcode=1992JGR....9711011C |doi=10.1029/92JB00653 |issn=2156-2202 |hdl=1808/17129|hdl-access=free }}</ref><ref name=":8">{{Cite journal |last1=Aleinikoff |first1=J. N. |last2=Nielson |first2=D. L. |last3=Hedge |first3=C. E. |last4=Evans |first4=S. H. |date=1986 |title=Geochronology of Precambrian and Tertiary rocks in the Mineral Mountains, south-central Utah |journal=US Geological Survey Bulletin |volume=1622 |pages=1–12}}</ref> Roosevelt Hot Springs (RHS) to the east is a hydrothermal area with temperatures ranging from about 100'''°'''C at the surface to over 250&nbsp;°C at a depth of roughly 4000 meters (13,123.4&nbsp;ft).<ref name=":6" /> These temperatures indicate the presence of cooling [[magma]] in the shallow [[Crust (geology)|crust]].<ref name=":6" />

== Research ==
More than 80 shallow gradient wells (<500 m depth) and 20 deeps wells (>500 m depth) were drilled.<ref name=":32">{{Cite journal |last1=Allis |first1=Rick |last2=Moore |first2=Joe |last3=Davatzes |first3=Nick |last4=Gwynn |first4=Mark |last5=Hardwick |first5=Christian |last6=Kirby |first6=Stefan |last7=McLennan |first7=John |last8=Pankow |first8=Kris |last9=Potter |first9=Stephen |last10=Simmons |first10=Stuart |date=February 22–24, 2016 |title=EGS Concept Testing and Development at the Milford, Utah FORGE Site |url=https://pangea.stanford.edu/ERE/pdf/IGAstandard/SGW/2016/Allis.pdf |journal=Standford University in Standford CA, 41st Workshop on Geothermal Reservoir Engineering |volume=SGP-TR-209 |pages=13 |via=Pangea.Standford.edu}}</ref><ref name=":92">{{Cite journal |last=Allis |first=Rick |date=2018 |title=Thermal Characteristics of the FORGE site, Milford, Utah |url=https://publications.mygeoenergynow.org/grc/1033913.pdf |journal=Geothermal Resources Council Transactions |volume=42-15}}</ref> Analyses from the shallow well data reported that the encountered granitic rocks were not producing fluids, but were hot.<ref name=":32" /> A lack of fluid production indicated these rocks are impermeable and that the site is a classic example of a [[Hot dry rock geothermal energy|hot dry rock energy]] system.<ref name="auto" /> The thermal grounds cover most of the northern Milford valley.<ref name=":32" /><ref name=":92" /> The highest temperature wells (greater than 80&nbsp;°C) are located east of the OMF above the RHS [[Hydrothermal circulation|hydrothermal]] system.<ref name=":92" /> Near-surface profiles (less than 80 m depth) of [[temperature gradient]] are similar in central, southern and western sectors at roughly 70&nbsp;°C per km and do not exceed 270&nbsp;°C, even at higher temperature wells to the west.<ref name=":92" />

The primary well descends vertically 6,000 feet (1.8&nbsp;km), then continues 5,000 feet (1.5 kilometers)  at a 65 degree angle. The well employed a diamond-tipped bit, cutting drilling costs by 20 percent.<ref name=":1">{{Cite magazine |last=Barber |first=Gregory |title=A Vast Untapped Green Energy Source Is Hiding Beneath Your Feet |language=en-US |magazine=Wired |url=https://www.wired.com/story/a-vast-untapped-green-energy-source-is-hiding-beneath-your-feet/ |access-date=2023-08-10 |issn=1059-1028}}</ref>

== References ==
{{Reflist}}

[[Category:Geothermal energy]]
[[Category:United States Department of Energy]]
[[Category:Beaver County, Utah]]
[[Category:2018 establishments in Utah]]