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• 1. [Image] The Marysville, Montana Geothermal Project (Revised)

  	The object of the Marysville Geothermal Project is to investigate a region of abnormally high geothermal heat flow near Marysville, MT, about 20 miles northwest of Helena. The research should determine ...
  	Citation × Citation Citation Abstract Copy Title: The Marysville, Montana Geothermal Project (Revised) Author: McSpadden, W.R. Year: 1974 The object of the Marysville Geothermal Project is to investigate a region of abnormally high geothermal heat flow near Marysville, MT, about 20 miles northwest of Helena. The research should determine the nature and size of the resource, how the energy might be extracted, the potential monetary value of the energy, and how similar resources elsewhere might be located. The heat source was expected to be a granitic pluton or magmatic intrusion, 10,000 to 40,000 years old, with temperatures in the range of 300 to 500°C. Originally it was thought that the pluton was at relatively shallow depths, but at present its depth and exact location are unknown Title: The Marysville, Montana Geothermal Project (Revised) Author: McSpadden, W.R. Year: 1974 The object of the Marysville Geothermal Project is to investigate a region of abnormally high geothermal heat flow near Marysville, MT, about 20 miles northwest of Helena. The research should determine the nature and size of the resource, how the energy might be extracted, the potential monetary value of the energy, and how similar resources elsewhere might be located. The heat source was expected to be a granitic pluton or magmatic intrusion, 10,000 to 40,000 years old, with temperatures in the range of 300 to 500°C. Originally it was thought that the pluton was at relatively shallow depths, but at present its depth and exact location are unknown Close

• 2. [Image] Geothermal Exploration of the Puga and Chumathang Geothermal Fields, Ladakh, India

  	Puga and Chumathang Geothermal fields are situated near the collided junction of the Indian and Asian Crystal plates and thermal activity in these fields is attributed to the widespread igneous activity ...
  	Citation × Citation Citation Abstract Copy Title: Geothermal Exploration of the Puga and Chumathang Geothermal Fields, Ladakh, India Author: Shanker, R. Puga and Chumathang Geothermal fields are situated near the collided junction of the Indian and Asian Crystal plates and thermal activity in these fields is attributed to the widespread igneous activity of Upper Cretaceous to late Tertiary age. A deep suture zone, recognised in between these two fields and the associated faults provide channels for the upward migration of the thermal fluids. High concentrations of Cl, F, Si02, B, Na, Li, Rb, Cs in thermal fluids signify contribution of magmatic bodies towards heat, and fluid supply. These fields are characterized by high heat flow conditions (13 HFU), abnormal shallow geothermal gradients (0.7 - 2.5 c/m) , high base temperature (220 - 270 C) as obtained by alkalia and Ne-K-Ca geothermometry and low resistivity values (2-20 ohm.m.). Low resistivity zones occupy on an area of three and one sq.km. and extend down to maximum depths of 300 m. and 130 m. at Puga and Chumathang respectively. Shallow drilling (28-130 m.) has established the existence of wet steam reservoirs under moderate pressure (2-4.5 kg/cm^2). Hot fluid (95-135 C) discharges from eight flowing wells ranged from 7.5 to 30 t/h. These thermal fluids are stored in the partly consolidated fluvioglacial deposits of Quarternary to Recent age. The occurrence of a limestone layer in the country rock at Puga brightens the prospects of getting good reservoir at depth. In both these fields two aquifers have been recognised, each having sizeable potential for retaining ground water. The ground water recharge is mainly through snow melt from glaciers in the case of Puga field and principally from Indus river in the case of Chumathangfield Title: Geothermal Exploration of the Puga and Chumathang Geothermal Fields, Ladakh, India Author: Shanker, R. Puga and Chumathang Geothermal fields are situated near the collided junction of the Indian and Asian Crystal plates and thermal activity in these fields is attributed to the widespread igneous activity of Upper Cretaceous to late Tertiary age. A deep suture zone, recognised in between these two fields and the associated faults provide channels for the upward migration of the thermal fluids. High concentrations of Cl, F, Si02, B, Na, Li, Rb, Cs in thermal fluids signify contribution of magmatic bodies towards heat, and fluid supply. These fields are characterized by high heat flow conditions (13 HFU), abnormal shallow geothermal gradients (0.7 - 2.5 c/m) , high base temperature (220 - 270 C) as obtained by alkalia and Ne-K-Ca geothermometry and low resistivity values (2-20 ohm.m.). Low resistivity zones occupy on an area of three and one sq.km. and extend down to maximum depths of 300 m. and 130 m. at Puga and Chumathang respectively. Shallow drilling (28-130 m.) has established the existence of wet steam reservoirs under moderate pressure (2-4.5 kg/cm^2). Hot fluid (95-135 C) discharges from eight flowing wells ranged from 7.5 to 30 t/h. These thermal fluids are stored in the partly consolidated fluvioglacial deposits of Quarternary to Recent age. The occurrence of a limestone layer in the country rock at Puga brightens the prospects of getting good reservoir at depth. In both these fields two aquifers have been recognised, each having sizeable potential for retaining ground water. The ground water recharge is mainly through snow melt from glaciers in the case of Puga field and principally from Indus river in the case of Chumathangfield Close

• 3. [Image] Research on the Physical Properties of Geothermal Reservoir Rock. Quarterly Report, March 1978

  	A laboratory study of the P-wave velocity and electric Resistivity was undertaken on Cenozoic Volcanic Rocks collected from the Columbia Plateau Volcanic basin (C) and the Jemez Volcanic field (NM). Electric ...
  	Citation × Citation Citation Abstract Copy Title: Research on the Physical Properties of Geothermal Reservoir Rock. Quarterly Report, March 1978 Author: Keller, G.V. Year: 1978 A laboratory study of the P-wave velocity and electric Resistivity was undertaken on Cenozoic Volcanic Rocks collected from the Columbia Plateau Volcanic basin (C) and the Jemez Volcanic field (NM). Electric resistivities of cylindrical samples saturated with 0.1 N NaCl solution were measured using a four electrode system and a 1.0 KHz frequency source. Seismic P-wave velocities were calculated from measured transit time of mechanical pulses generated and received by piezoelectric transducers. The electric Resistivity of water saturated Samples decreased as temperature increased to the boiling point of water. Above boiling point, Resistivity increased rapidly as water changed to vapor. Resistivity is most sensitive to temperature changes between 35/sup 0/C to 65/sup 0/C. Resistivities of samples increased with decrease in saturation. The effect is more pronounced at lower temperatures. No dependence of seismic P-wave velocities on temperature was observed. Both Resistivity and P-wave velocity depend on porosity. The increase in porosity results in a decrease in the Resistivity formation factor. Assuming a relationship FF = a phi/sup -m/ (Archie's Law), where FF and phi represent the formation factor and porosity respectively, least squares indicate a variation of a between .5 and 2.0. The value of m varied between 1.2 to 1.7. Seismic velocities (v) decrease as porosity increases. Porosity appears to be linearly related to log v. Several Samples show anomalous relationship between porosity and Resistivity. Most of these samples also show anomalous seismic velocities. The majority of these samples have coarse grains or large pores. The effect of saturation on P-wave velocity is small and can be observed in few samples. In these samples, seismic velocities decrease with increase in saturation at high saturation (100% to 85%), and show a reverse relationship at low saturation. Between 15% and 85% saturation in velocity is constant Title: Research on the Physical Properties of Geothermal Reservoir Rock. Quarterly Report, March 1978 Author: Keller, G.V. Year: 1978 A laboratory study of the P-wave velocity and electric Resistivity was undertaken on Cenozoic Volcanic Rocks collected from the Columbia Plateau Volcanic basin (C) and the Jemez Volcanic field (NM). Electric resistivities of cylindrical samples saturated with 0.1 N NaCl solution were measured using a four electrode system and a 1.0 KHz frequency source. Seismic P-wave velocities were calculated from measured transit time of mechanical pulses generated and received by piezoelectric transducers. The electric Resistivity of water saturated Samples decreased as temperature increased to the boiling point of water. Above boiling point, Resistivity increased rapidly as water changed to vapor. Resistivity is most sensitive to temperature changes between 35/sup 0/C to 65/sup 0/C. Resistivities of samples increased with decrease in saturation. The effect is more pronounced at lower temperatures. No dependence of seismic P-wave velocities on temperature was observed. Both Resistivity and P-wave velocity depend on porosity. The increase in porosity results in a decrease in the Resistivity formation factor. Assuming a relationship FF = a phi/sup -m/ (Archie's Law), where FF and phi represent the formation factor and porosity respectively, least squares indicate a variation of a between .5 and 2.0. The value of m varied between 1.2 to 1.7. Seismic velocities (v) decrease as porosity increases. Porosity appears to be linearly related to log v. Several Samples show anomalous relationship between porosity and Resistivity. Most of these samples also show anomalous seismic velocities. The majority of these samples have coarse grains or large pores. The effect of saturation on P-wave velocity is small and can be observed in few samples. In these samples, seismic velocities decrease with increase in saturation at high saturation (100% to 85%), and show a reverse relationship at low saturation. Between 15% and 85% saturation in velocity is constant Close