1
North Dakota Geological Survey 100K Series: Bwmn - g - Ml Cartographic Compilation: E. L. Kadrmas Edward C. Murphy, State Geologist Lynn D. Helms, Director Dept. of Mineral Resources -5000 -5500 -6000 -4500 L i t t l e M i s s o u r i R i v e r I n d ian C r e e k C a s h C r e e k B o y c e C r e e k C a n n o n b a l l C re e k Mud C r e ek N o rth B u t t e Cr e e k B ut te So u t h B u t t e C r e e k Ba c o n C r e e k H a y C r e e k B e a v e r C r e e k W o r s e r Co y o t e C r e ek Sp r i n g C r e e k Sp ring Lake Spr in g C r e e k L i t t l e R i v e r M i s s o u r i K i d C r e e k Bi g G u m b o C r e e k S ev e n m i l e C r e e k F i ve m il e C r e e k No r th F o r k G r a n d R i v e r A l k a l i C r e e k C o l d T u r k e y Cr e e k S p r i n g C r e e k Ka lina Lake S t a g e C r e e k S p r i n g C r e e k Bowman-Haley Lake L i g h t n i ng C r e e k B u ff a l o C r ee k S pri ngs La ke Gas co yne La ke De e p C r e e k De e p Cr e e k W e st F o r k Ea s t Fo r k Stewart Lake S a nd C r e e k C e d ar C r ee k N o r t h Fo r k S o u t h F o r k N o r t h C e d a r C r e e k C h a n t a P e t a C r e e k R i v e r C a n n o n b a l l White Lake ( / 85 ( / 85 ( / 85 ( / 85 ( / 12 ( / 12 ! ( 67 ! ( 67 ( / 12 ( / 12 SLOPE COUNTY BOWMAN COUNTY SLOPE COUNTY BOWMAN COUNTY F o r k G r a n d Ri v e r N o r t h F o r k G ra n d Ri v e r L o n e T r e e C r e e k C r ee k B o x el d e r Bu ffa lo Cr e e k L i tt l e C r e e k N o rt h Rhame Bowman Amidon Gascoyne Scranton Marm ar th 6 6 1 1 1 1 1 1 6 1 1 1 1 1 1 1 1 6 1 6 1 6 1 1 6 6 1 1 1 1 6 1 1 1 1 1 1 6 6 1 1 1 1 6 1 1 1 6 1 6 1 6 6 6 1 6 1 6 6 1 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 1 1 1 6 6 31 36 36 36 31 36 36 31 36 36 36 36 36 36 31 31 31 36 31 36 36 36 31 36 36 36 36 31 36 36 36 36 31 36 36 31 31 36 31 31 36 36 31 36 36 36 31 36 36 36 31 36 31 36 31 36 31 36 31 36 36 36 31 31 31 31 36 36 36 36 36 36 31 36 31 31 31 31 31 31 31 36 31 31 36 31 31 31 36 31 31 36 31 31 36 36 31 31 31 36 31 36 31 31 31 31 31 31 31 31 31 31 36 36 36 36 31 31 31 1 1 1 6 6 1 6 6 6 1 1 1 1 6 1 6 6 Lorraine A. Manz 2009 Note: This map was exp an ded beyond the normal Bowman 100K Sheet to include an additional w idth of two miles west to the Montan a b order and an additio nal height of four miles south to the South Dakota border. 103 o 00 ' 46 o 30 ' R. 105 W. R. 103 W. R. 102 W. R. 101 W. R. 100 W. R. 98 W. R. 99 W. R. 104 W. R. 106 W. 104 o 00 ' 46 o 30 ' T. 135 N. T. 133 N. T. 131 N. T. 130 N. T. 132 N. T. 134 N. T. 129 N. 104 o 00 ' 46 o 00 ' 103 o 00 ' 46 o 00 ' R. 106 W. R. 104 W. R. 105 W. R. 103 W. R. 102 W. R. 101 W. R. 100 W. R. 99 W. R. 107 W. Deep Geothermal Resources: Estimated Temperatures on Top of the Lodgepole Formation Bowman 100K Sheet, North Dakota Bowma n 1 00K Sheet, N orth Dakota 1981 Magnetic North Declination at Center of Sheet 13 o Adjoining 100K Maps ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! (! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( 104 o 00 ' 46 o 30 ' 103 o 00 ' 46 o 30 ' 104 o 00 ' 46 o 00 ' 103 o 00 ' 46 o 00 ' Mercator Projection 1927 North American Datum Standard parallel 46 o 00 ' Central meridian 103 o 30 ' 0 1 2 3 4 Mile s Scale 1:100,000 Figure 1. Data Points (wells) Other Features Wa ter County Boundary River/Stream - Intermittent Paved Road Water - Intermittent ( / 12 US Highway River/Stream - Perennial State Highway ! ( 67 Section Corners E Unpaved Road 100K Border Geologic Symbols Top of Lodgepole Formation (feet above sea level) Geothermal energy is a renewable resource capable of producing an uninterrupted supply of electrical power and heat. In stable sedimentary basins, low-temperature geothermal energy (< 40°C, < 100 o F) is extracted from the shallow subsurface (~8-600 feet, 2.5-200 m) for use in domestic and commercial heating and cooling systems. Historically, deeper, hotter resources in these regions have not been developed because they typically lack one or more of the essential requirements that make high-temperature geothermal resources technically and economically viable. Conventional methods of generating electricity using geothermal energy rely on hot (> 100°C, > 212 o F) relatively shallow (< 10,000 feet, < 3000 m), easily developed hydrothermal resources. Generally associated with active plate boundaries and/or volcanism, these high-grade hydrothermal systems are characterized by high thermal gradients, and highly fractured, porous reservoir rocks through which natural waters or steam can freely circulate. Large-scale, cost-effective electric power generation usually requires fluid temperatures above 150°C (300 o F) but smaller systems based on standard binary-cycle technology are capable of producing electricity using geothermal fluids at temperatures as low as 100°C (212 o F). Natural sources of high-grade hydrothermal energy are geographically limited. In the U.S. they are restricted to the western states and currently represent less than 1% of the nation’s electrical power generating capacity. Yet the amount of heat at depths less than 30,000 feet (10,000 m) below the surface of the continental U.S. is substantial. By replicating natural hydrothermal conditions it is possible, in some regions, to turn this heat into an economically viable resource. In 2005 an 18-member MIT-led interdisciplinary panel conducted a comprehensive technical and economic assessment of geothermal energy as a viable source of energy for the U.S. (U.S. Department of Energy, 2006). The study estimated that, based on current technology, geothermal energy could be producing more than 100GW of affordable electricity by 2050, equivalent to roughly10% of the present-day capacity of the U.S. Enhanced (or engineered) geothermal systems (EGS) are engineered reservoirs designed to produce energy as heat or electricity from geothermal resources that are otherwise not economical due to lack of water and/or permeability (U.S. Department of Energy, 2008). EGS technology uses adaptations of techniques developed in the oil and gas, and mining industries to fracture hot, low-porosity rocks in the deep subsurface and extract the heat with water via a system of injection and production wells. With infrastructures already in place and the abundance of horizontally drilled and/or artificially stimulated wells, oil and gas fields are prime candidates for the application of EGS technology. Of particular interest are those wells regarded as marginal or unproductive because they produce too much water. Geothermal waters that are coproduced with oil and gas are an expensive waste product that must be disposed of either in evaporation ponds or by re-injection into the subsurface. If sufficiently hot (> 100°-150°C, > 212°-300°F) and available in sufficient quantity, however, these waters may be capable of generating cost-effective electricity (McKenna and others, 2005). The Lodgepole Formation is the basal unit of the Mississippian-age Madison Group, and is the second-shallowest of four major geothermal aquifers that occur in the Williston Basin. In southwestern North Dakota hot (> 100°C, > 212 o F), low-salinity waters from the Lodgepole Formation are co-produced with oil and gas. The map shows calculated temperatures (°C) for the top of the Lodgepole Formation in the vicinity of Bowman in southwestern North Dakota. System Thermal Conductivity (W/m K) Quaternary 1.4 Tertiary 1.2 Cretaceous 1.2 Jurassic 1.3 Triassic 1.3 Permian 2.9 Pennsylvanian 1.7 Mississippian 2.9 Table 1: Thermal conductivity estimates from Gosnold (2007) Regional heat flow Q = 64-65 mW/m 2 (Gosnold, 1984, p. 15). Rock units and thicknesses were obtained from oil well log tops (July 2008 update). The map was compiled using approximately 180 data points (wells) (fig. 1). Estimated temperatures ranged from 104°C (219°F) to 136°C (277°F) in this map sheet. References Gosnold,W.D. Jr., 1984, Geothermal resource assessment for North Dakota. Final report: U.S Department of Energy Bulletin No. 84-04-MMRRI-04. Gosnold, W.D. Jr., 2007, A new look at geothermal energy as an energy choice for the future: AAPG Annual Convention and Exhibition, Long Beach, Calif., 2007. McKenna, J., Blackwell, D., Moyes, C., and Patterson, P. D., 2005, Geothermal electric power supply possible from Gulf Coast, Midcontinent oil field waters: Oil & Gas Journal, Sept. 5, 2005 p. 34-40. Tester, J. W., Anderson, B., Batchelor, A., Blackwell, D., DiPippo, R., Drake, E., Garnish, J., Livesay, B., Moore, M.C., Nichols, K., Petty, S., Toksoz, N., Veatch, R., Augustine, C., Baria, R., Murphy, E., Negraru, P., Richards, M., 2006., The future of geothermal energy: Impact of enhanced geothermal systems (EGS) on the United States in the 21 st century: Massachusetts Institute of Technology, DOE Contract DE-AC07-05ID14517, Final Report. U.S. Department of Energy, 2008, Enhanced geothermal Systems: http://www1.eere.energy.gov/geothermal/enhanced_geothermal_systems.html (Version 9/24/2008). 104 106 108 110 112 114 116 118 120 122 124 124 130 130 132 134 136 126 112 106 Temperature/ o C 128 118 There are no data sets for North Dakota that list accurate temperatures for Paleozoic rocks. Bottom hole temperatures from oil well logs are unreliable and to assume that a simple linear relationship exists between temperature and depth would be incorrect. Although grossly linear the geothermal gradient in the upper lithosphere is significantly affected by thermal variables (heat flow and thermal conductivity) in the earth’s crust and any method used to accurately calculate subsurface temperatures must take these factors into account. Provided the subsurface stratigraphy is known, Gosnold (1984) showed that at a given depth (Z) the temperature (T) can be represented by the following equation: T = T o + n i 1 Z i (Q/K i ) Where: T o = Surface temperature (in °C) Z i = Thickness of the overlying rock layer (in meters) K i = Thermal conductivity of the overlying rock layer N = Number of overlying rock layers Q = Regional heat flow For the data set used to produce this map T 0 and K were assumed to be constants. Mean surface temperature (T 0 = 5.1°C, 41°F) was calculated from monthly station normals (at Bismarck Municipal Airport, Fargo Hector Airport, Grand Forks International Airport, and Williston Sloulin Airport) for the period 1971 to 2000 (http://cdo.ncdc.noaa.gov/climatenormals/clim81/NDnorm.pdf). Thermal conductivities (K) for formations overlying the Lodgepole Formation are shown in Table 1.

North Dakota Geological Survey Edward C. Murphy, State ... maps/Bowman100k/bwmn_100k_g_Ml.pdfThe Lodgepole Formation is the basal unit of the Mississippian-age Madison Group, and is

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Page 1: North Dakota Geological Survey Edward C. Murphy, State ... maps/Bowman100k/bwmn_100k_g_Ml.pdfThe Lodgepole Formation is the basal unit of the Mississippian-age Madison Group, and is

North Dakota Geological Survey100K Series: Bwmn - g - Ml

Cartographic Compilation : E. L. Kadrmas

Edward C. Murphy, State GeologistLynn D. Helms, Director Dept. of Mineral Resources

-5000

-5500

-6000

-4500

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M i s s o u r i

R i v e r

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Boyce

Creek

Can non ball Creek

Mud

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North Butte Cr eek

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Hay

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1 11 6 61 6661 1 11 6 16 6

Lorraine A. Manz2009

Note: This map was exp an ded beyond the normal Bowman 100K Sheet to include an addit ional w idth of two miles west to the Montan a b order and an additio nal height of four milessouth to the So uth Dakota border.

103o 00 '

46o 30 'R. 105 W. R. 103 W. R. 102 W. R. 101 W. R. 100 W. R. 98 W.R. 99 W.R. 104 W.R. 106 W.104o 00 '

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103o 00 '

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R. 106 W. R. 104 W.R. 105 W. R. 103 W. R. 102 W. R. 101 W. R. 100 W. R. 99 W.R. 107 W.

Deep Geothermal Resources: Estimated Temperatures on Top of the Lodgepole FormationBowman 100K Sheet, North Dakota

Bowma n 1 00K Sheet, N orth Dakota

1981 Magnetic No rthDeclinatio n at Cen ter of Sh eet

13o

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104o 00 '

46o 30 '103o 00 '

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104o 00 '

46o 00 '

103o 00 '

46o 00 '

Merca tor Projection 1927 Nor th American DatumStandard parallel 46o 00' Central meridian 103o 30'

0 1 2 3 4

Miles

Scale 1:100,000

Figure 1. Data Points (wells)

Other FeaturesWater

County Boundary

River/Stream - Intermittent

Paved RoadWater - Intermittent

(/12 US HighwayRiver/Stream - Perennial

State Highway!(67Section CornersE

Unpaved Road

100K Border

Geologic SymbolsTop of Lodgepole Formation (feet above sea level)

Geothermal energy is a renewable resource capable of producing an uninterrupted supply of electrical power and heat. In stable sedimentary basins, low-temperature geothermal energy (< 40°C, < 100oF) is extracted from the shallow subsurface (~8-600 feet, 2.5-200 m) for use in domestic and commercial heating and cooling systems. Historically, deeper, hotter resources in these regions have not been developed because they typically lack one or more of the essential requirements that make high-temperature geothermal resources technically and economically viable. Conventional methods of generating electricity using geothermal energy rely on hot (> 100°C, > 212oF) relatively shallow (< 10,000 feet, < 3000 m), easily developed hydrothermal resources. Generally associated with active plate boundaries and/or volcanism, these high-grade hydrothermal systems are characterized by high thermal gradients, and highly fractured, porous reservoir rocks through which natural waters or steam can freely circulate. Large-scale, cost-effective electric power generation usually requires fluid temperatures above 150°C (300oF) but smaller systems based on standard binary-cycle technology are capable of producing electricity using geothermal fluids at temperatures as low as 100°C (212oF). Natural sources of high-grade hydrothermal energy are geographically limited. In the U.S. they are restricted to the western states and currently represent less than 1% of the nation’s electrical power generating capacity. Yet the amount of heat at depths less than 30,000 feet (10,000 m) below the surface of the continental U.S. is substantial. By replicating natural hydrothermal conditions it is possible, in some regions, to turn this heat into an economically viable resource. In 2005 an 18-member MIT-led interdisciplinary panel conducted a comprehensive technical and economic assessment of geothermal energy as a viable source of energy for the U.S. (U.S. Department of Energy, 2006). The study estimated that, based on current technology, geothermal energy could be producing more than 100GW of affordable electricity by 2050, equivalent to roughly10% of the present-day capacity of the U.S. Enhanced (or engineered) geothermal systems (EGS) are engineered reservoirs designed to produce energy as heat or electricity from geothermal resources that are otherwise not economical due to lack of water and/or permeability (U.S. Department of Energy, 2008). EGS technology uses adaptations of techniques developed in the oil and gas, and mining industries to fracture hot, low-porosity rocks in the deep subsurface and extract the heat with water via a system of injection and production wells. With infrastructures already in place and the abundance of horizontally drilled and/or artificially stimulated wells, oil and gas fields are prime candidates for the application of EGS technology. Of particular interest are those wells regarded as marginal or unproductive because they produce too much water. Geothermal waters that are coproduced with oil and gas are an expensive waste product that must be disposed of either in evaporation ponds or by re-injection into the subsurface. If sufficiently hot (> 100°-150°C, > 212°-300°F) and available in sufficient quantity, however, these waters may be capable of generating cost-effective electricity (McKenna and others, 2005). The Lodgepole Formation is the basal unit of the Mississippian-age Madison Group, and is the second-shallowest of four major geothermal aquifers that occur in the Williston Basin. In southwestern North Dakota hot (> 100°C, > 212oF), low-salinity waters from the Lodgepole Formation are co-produced with oil and gas. The map shows calculated temperatures (°C) for the top of the Lodgepole Formation in the vicinity of Bowman in southwestern North Dakota.

System Thermal Conductivity (W/m K) Quaternary 1.4 Tertiary 1.2 Cretaceous 1.2 Jurassic 1.3 Triassic 1.3 Permian 2.9 Pennsylvanian 1.7 Mississippian 2.9

Table 1: Thermal conductivity estimates from Gosnold (2007) Regional heat flow Q = 64-65 mW/m2 (Gosnold, 1984, p. 15). Rock units and thicknesses were obtained from oil well log tops (July 2008 update). The map was compiled using approximately 180 data points (wells) (fig. 1). Estimated temperatures ranged from 104°C (219°F) to 136°C (277°F) in this map sheet. References Gosnold,W.D. Jr., 1984, Geothermal resource assessment for North Dakota. Final report: U.S Department of Energy Bulletin No. 84-04-MMRRI-04. Gosnold, W.D. Jr., 2007, A new look at geothermal energy as an energy choice for the future: AAPG Annual Convention and Exhibition, Long Beach, Calif., 2007. McKenna, J., Blackwell, D., Moyes, C., and Patterson, P. D., 2005, Geothermal electric power supply possible from Gulf Coast, Midcontinent oil field waters: Oil & Gas Journal, Sept. 5, 2005 p. 34-40.

Tester, J. W., Anderson, B., Batchelor, A., Blackwell, D., DiPippo, R., Drake, E., Garnish, J., Livesay, B., Moore, M.C., Nichols, K., Petty, S., Toksoz, N., Veatch, R., Augustine, C., Baria, R., Murphy, E., Negraru, P., Richards, M., 2006., The future of geothermal energy: Impact of enhanced geothermal systems (EGS) on the United States in the 21st century: Massachusetts Institute of Technology, DOE Contract DE-AC07-05ID14517, Final Report.

U.S. Department of Energy, 2008, Enhanced geothermal Systems: http://www1.eere.energy.gov/geothermal/enhanced_geothermal_systems.html (Version 9/24/2008).

104

106

108

110

112

114

116

118

120

122

124

124130

130

132

134

136

126

112 106Temperature/oC

128

118

There are no data sets for North Dakota that list accurate temperatures for Paleozoic rocks. Bottom hole temperatures from oil well logs are unreliable and to assume that a simple linear relationship exists between temperature and depth would be incorrect. Although grossly linear the geothermal gradient in the upper lithosphere is significantly affected by thermal variables (heat flow and thermal conductivity) in the earth’s crust and any method used to accurately calculate subsurface temperatures must take these factors into account. Provided the subsurface stratigraphy is known, Gosnold (1984) showed that at a given depth (Z) the temperature (T) can be represented by the following equation: T = To +

n

i 1Zi(Q/Ki)

Where: To = Surface temperature (in °C) Zi = Thickness of the overlying rock layer (in meters) Ki = Thermal conductivity of the overlying rock layer N = Number of overlying rock layers Q = Regional heat flow For the data set used to produce this map T0 and K were assumed to be constants. Mean surface temperature (T0 = 5.1°C, 41°F) was calculated from monthly station normals (at Bismarck Municipal Airport, Fargo Hector Airport, Grand Forks International Airport, and Williston Sloulin Airport) for the period 1971 to 2000 (http://cdo.ncdc.noaa.gov/climatenormals/clim81/NDnorm.pdf). Thermal conductivities (K) for formations overlying the Lodgepole Formation are shown in Table 1.