Isotope hydrogeology and geothermometry of the Mount Meager geothermal area

1982 ◽  
Vol 19 (7) ◽  
pp. 1454-1473 ◽  
Author(s):  
I. D. Clark ◽  
P. Fritz ◽  
F. A. Michel ◽  
J. G. Souther
Keyword(s):  
Inorganic Carbon ◽  
Dissolved Inorganic Carbon ◽  
Environmental Isotopes ◽  
Thermal Waters ◽  
Geothermal System ◽  
Altitude Effect ◽  
Geothermal Resources ◽  
Geothermal Waters ◽  
Maximum Temperatures ◽  
Cold Groundwaters

A survey of stable and radioactive environmental isotopes has been carried out in order to investigate the recharge, thermal history, age, and geothermometry of the thermal waters at Mount Meager, British Columbia, a Quaternary volcano that is currently the site of active exploration for geothermal resources. Isotope determinations include 18O, 2H, and 3H in precipitation, thermal and cold groundwaters, and glacier ice; 13C and 14C in dissolved inorganic carbon; 18O and 34S in dissolved sulphate from thermal and cold groundwaters; and 13C and 18O in hydrothermal calcite crystals. Major ion analyses were performed on thermal and cold spring waters.Precipitation data are used to define the local meteoric water line and to document the altitude effect on waters recharging the geothermal system, demonstrating that there are two hydrogeologically separate reservoirs recharged at different altitudes. Both pools of geothermal waters have experienced shifts of between +0.5 and +2.5‰ in δ18O values, indicating a limited degree of 18O exchange with hot silicate minerals.Tritium contents indicate that these waters recharged prior to 1955. 13C contents of dissolved inorganic carbon and hydrothermal calcites from drill core document contamination of the thermal waters with "dead" volcanogenic CO2 plus carbon exchange with fracture calcite, which precludes the possibility of "dating" the thermal waters using 14C.Several chemical and isotopic geothermometers are used to estimate the maximum temperatures experienced by the thermal waters. The fractionation of 18O between SO42− and H2O in these waters gives calculated maximum temperatures of less than 140 °C. The Mg-corrected Na–K–Ca geothermometer shows excellent correlation with the SO4–H2O estimates with maximum temperatures of less than 140 °C. Fractionation of 13C and 18O in the systems CaCO3–CO2 and CaCO3–H2O using hydrothermal calcites and borehole fluids also offers no indications of subsurface temperatures in excess of 140 °C. Silica geothermometer results are not reliable because of equlibrium with amorphous silica phases in the subsurface.It is concluded that these thermal waters are not deeply circulating and have not experienced temperatures in excess of 140 °C.

scholarly journals Numerical modeling as a tool for evaluating the renewability of geothermal resources: the case study of the Euganean Geothermal System (NE Italy)

2021 ◽  
Author(s):  
Filippo Torresan ◽  
Leonardo Piccinini ◽  
Mauro Cacace ◽  
Marco Pola ◽  
Dario Zampieri ◽  
...  
Keyword(s):  
System Development ◽  
Sharp Decrease ◽  
Scenario Planning ◽  
Thermal Waters ◽  
Geothermal System ◽  
Veneto Region ◽  
Geothermal Resources ◽  
Ne Italy ◽  
Human Footprint ◽  
Geological Processes

AbstractRenewable natural resources are strategic for reducing greenhouse gas emissions and the human footprint. The renewability of these resources is a crucial aspect that should be evaluated in utilization of scenario planning. The renewability of geothermal resources is strictly related to the physical and geological processes that favor water circulation and heating. In the Veneto region (NE Italy), thermal waters of the Euganean Geothermal System are the most profitable regional geothermal resource, and its renewability assessment entails the evaluation of fluid and heat recharge, regional and local geological settings, and physical processes controlling system development. This renewability assessment is aimed at defining both the importance of such components and the resource amount that can be exploited without compromising its future preservation. In the second part of the twentieth century, the Euganean thermal resource was threatened by severe overexploitation that caused a sharp decrease in the potentiometric level of the thermal aquifers. Consequently, regulation for their exploitation is required. In this work, the renewability of the Euganean Geothermal System was assessed using the results from numerical simulations of fluid flow and heat transport. The simulations were based on a detailed hydrogeological reconstruction that reproduced major regional geological heterogeneities through a 3D unstructured mesh, while a heterogeneous permeability field was used to reproduce the local fracturing of the thermal aquifers. The model results highlight the role played by the resolved structural elements, in particular the subsurface high-angle faults of the exploitation field, and by the anomalous regional crustal heat flow affecting the central Veneto region.

scholarly journals Isotopic Investigation of the Surdulica Geothermal System

Radiocarbon ◽  
1989 ◽  
Vol 31 (03) ◽  
pp. 893-901 ◽  
Author(s):  
Branislav Milovanović ◽  
Svetislav Stanković ◽  
Miomir Komatina ◽  
Munevera Hadžišehović ◽  
Mladen Župančić ◽  
...  
Keyword(s):  
Stable Isotope ◽  
Meteoric Water ◽  
Thermal Waters ◽  
Geothermal System ◽  
Independent Data ◽  
Recharge Area ◽  
Tritium Content ◽  
Geothermal Waters ◽  
Water Formation ◽  
Natural Springs

The object of our investigation was to study a mechanism of water formation in the Surdulica geothermal system (recharge area, age and homogeneity of the waters). We collected 56 samples to determine the chemical, stable isotope, 14C and tritium content of the waters. We found large stable isotope variations in precipitation collected at different altitudes, whereas the geothermal waters are largely homogeneous and seasonally independent. Data on springs and rivers, the local meteoric water line and recharge area were obtained. Three groups of groundwater were identified by age – modern from natural springs, old from mines and very old from the Vranjska Banja. Because the initial 14C activity of infiltrated waters from the recharge area is unknown, the age of thermal waters can only be inferred, from HCO3 −, 14C and 3H content, to be 10,000 to 28,000 years old.

scholarly journals Radiocarbon Concentration and Origin of Thermal Karst Waters in the Region of the Bükk Mountains, Northeastern Hungary

Radiocarbon ◽  
1995 ◽  
Vol 37 (2) ◽  
pp. 543-550 ◽  
Author(s):  
Ede Hertelendi ◽  
Mihály Veres ◽  
István Futó ◽  
Éva Svingor ◽  
Lajos Mikó ◽  
...  
Keyword(s):  
Thermal Water ◽  
Inorganic Carbon ◽  
Dissolved Inorganic Carbon ◽  
Karst Aquifer ◽  
Thermal Waters ◽  
Karst Water ◽  
Recharge Area ◽  
Karst Springs ◽  
Karst Waters ◽  
Karst Systems

Karst springs are abundant in Hungary, and many are thermal (temperatures >30°). As thermal springs are a significant part of Hungary's water resources, it is important to quantify their travel times in the karst systems. Thus, we chose to measure T and δ18O in the water and δ13C and 14C in dissolved inorganic carbon (DIC) in water from 50 thermal and nonthermal springs and wells in the Bükk Mountains, northeastern Hungary. Environmental isotope data confirm the karst water-flow pattern implied by earlier studies. We found the water in warm springs and boreholes to be mixtures of cold young and old thermal water. We also determined short mean-residence times for some large cold springs. The 14C activities measured in these springs indicate that the recharge area of the karst aquifer is open to the atmosphere, and atmospheric CO2 contributes to the 14C activity of these groundwaters. We observed good correlation between 14C and 3H activities and we determined negative correlations between 14C concentration and δ13C values and temperature. From the δ18O values of the oldest thermal waters, we attribute their origin to precipitation during colder temperatures than at present.

POTENSI PENGEMBANGAN PEMBANGKIT LISTRIK PANASBUMI SUHU RENDAH DI KABUPATEN MANOKWARI SELATAN

2014 ◽  
Vol 13 (3) ◽  
Author(s):  
Agustinus Denny Unggul Raharjo
Keyword(s):  
Population Growth ◽  
Natural Resources ◽  
Geothermal System ◽  
Reservoir Temperature ◽  
Geothermal Resources ◽  
Autonomous Region ◽  
Electric Generator ◽  
Binary Cycle ◽  
West Papua ◽  
The Government

<p class="BodyA">South Manokwari Regency is a new autonomous region in West Papua Province with abundant natural resources. As a new autonomous region South Manokwari Regency will be experiencing significant population growth. Population growth along with development and modernization will give burden to electricity demand. Alternatively, electricity can be provided with geothermal resources in Momiwaren District. Based on survey conducted by the government through the Geology Resources Centre in 2009, the reservoir temperature of the geothermal sources is 84<sup>o</sup>C with non volcanic geothermal system. Thus, the geothermal resources in South Manokwari Regency could be developed into binary cycle electric generator.</p>

scholarly journals Hydrogeochemical Characterization as a Tool to Recognize “Masked Geothermal Waters” in Bahía Concepción, Mexico

Resources ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 23
Author(s):  
Pablo Hernández-Morales ◽  
Jobst Wurl ◽  
Carlos Green-Ruiz ◽  
Diego Morata
Keyword(s):  
Spatial Distribution ◽  
Thermal Water ◽  
Elevated Temperatures ◽  
Ph Value ◽  
Spring Water ◽  
Geothermal Resources ◽  
Geothermal Waters ◽  
New Approach ◽  
Deep Reservoir ◽  
Hydrogeochemical Characterization

Geo-thermalism has been widely recognized on the Baja California Peninsula, especially during the last decade. The current research, carried out on Bahia Concepcion, evidences the existence of geothermal springs, which get recharged mainly by groundwater and seawater. The groundwater can be characterized as Na+-Cl− and Na+-HCO3− type, with a pH value close to neutrality. The slightly more acidic thermal sites presented temperatures between 32 °C and 59 °C at the surface. Based on the relationships of the Cl− and Br−, as well as the B/Cl−, and Br−/Cl− ratios, seawater was recognized as the main source of salinity. The spatial distribution is explained directly through marine intrusion, or via sprays and aerosols within the rainwater. Seawater ratios in thermal springs varied from 62% to 83%, corresponding mainly to shallow inflow, but seawater inputs into the deep thermal reservoir were also recognized. Temperatures in the geothermal deep reservoir were inferred from 114 to 209 °C, calculated through the SiO2 and Na+-K+ geothermometers. In addition to previously reported thermal sites at Bahía Concepción, and based on their elevated temperatures, two new sites were identified. Another five springs do not fulfill the commonly used definition, based on differential temperature, but show the typical hydrogeochemical signature of thermal water. A new approach to identify this low-temperature geothermal-influenced spring water by its hydrogeochemical composition is presented, for which the term “Masked Geothermal Waters” (MGW) is introduced. Our findings increase the area of the geothermal anomaly and, therefore, the potential of geothermal resources. The approach proposed in this research will also be useful to identify more MGW in other coastal areas.

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