El Tatio Research Articles

Direct Use of Geothermal Energy in Circum-Pacific Region: ABSTRACT

Geothermal energy is being utilized for direct use projects in several countries in the Circum-Pacific region. New Zealand has numerous projects in space conditioning and industrial processing. Most notable are the space heating in Rotorua, pulp and paper processing at Kawerau, sulfur extraction, alfalfa dehydration, and a planned salt extraction plant. At Tiwi, in the Philippines, experimental work has been carried out on salt production, grain drying, fish canning, and refrigeration. Many diverse uses have been attempted in Japan, including greenhouses, animal husbandry (chickens) fish breeding, carp, eel and alligator raising, space heating, pavement snow melting, and bathing. Presently, two national projects are under investigation at Shizukuishi, Iwate, and Kazuno, A ita. A cascaded use for district heating, greenhouse, snow melting, animal husbandry, and fish breeding is planned with water supplied from the Kakkonda and Onuma power plants. Experimental work is being carried on in Taiwan, especially in lumber and cereal drying. The People's Republic of China has been involved in wool piece goods and carpet manufacturing, using geothermal energy, along with poultry raising. Several district heating projects are planned in Tianjin and Beijing. The USA has planned space heating and greenhouse projects in Alaska, and has district heating projects under construction in Klamath Falls, Oregon, Boise, Idaho, Susanville, California, and Reno, Nevada. Onion dehydration and milk pasteurization are the only industrial processing uses. In Hawaii, near Puna, cane ugar and papaya processing plants, a cattle feed mill and an industrial park are being studied. Central and South America have no direct use projects in operation or under construction, however, a desalination plant is being considered for El Tatio, Chile. End_of_Article - Last_Page 975------------

The isotopic composition of waters from the El Tatio geothermal field, Northern Chile

On the basis of isotopic and chemical analyses of 45 spring, well and meteoric water samples from the El Tatio geothermal field in Northern Chile, four main processes giving rise to the formation of a wide range of thermal discharges can be distinguished. (1) Deep dilution of a predominant, primary high chloride (5500 mg/l, 260°) supply water derived from precipitation some 15 km east of El Tatio with local groundwater produces a secondary chloride water. (4750 mg/l, 190°) feeding springs over a limited area. (2) Single step steam separation from these two waters leads to isotopic shifts and increases in chloride contents to 8000 and 6000 mg/l respectively. (3) Absorption of this separated steam and carbon dioxide into local ground water and mixing with chloride waters at shallow levels produces a series of intermediate temperature (160°), low chloride, high bicarbonate waters. (4) Absorption of steam containing H 2S into surface waters leads to the formation of zero chloride, high sulfate waters; the isotopic enrichment observed is governed by a kinetic, steady state evaporation process.

47. Some consideration on the geothermal area of El Tatio, Chile(Abstracts of Papers submitted for the Meetings of the Society)

47. Some consideration on the geothermal area of El Tatio, Chile(Abstracts of Papers submitted for the Meetings of the Society)

Near-surface resistivity surveys of geothermal areas using the electromagnetic method

Electromagnetic surveys using the horizontal coplanar loop technique in the Broadlands field, New Zealand, and the El Tatio field, Chile, have provided information on resistivities to a depth of about 30 metres. The survey at Broadlands was largely experimental, while the survey at El Tatio was explorational using the techniques and data reduction methods which had proved satisfactory in New Zealand. The principal advantages of the electromagnetic method lie in its high speed and low cost, which make it an attractive alternative to direct temperature surveys. «In-phaseå and «quadratureå components at each of two frequencies were observed at field stations, giving four estimates of resistivity. These have been combined in the construction of the resistivity maps. In reducing the data it has been assumed that the ground resistivity is uniform down to the depth of maximum penetration. Within the limits set by volume considerations there is good correlation between resistivity down to 30 metres and temperatures measured at half this depth. The shape and areal extent of the low resistivity zone defined by the electromagnetic method at El Tatio are almost indistinguishable from those of the high temperature zone defined by direct temperature measurements.