Surface hydrothermal minerals and their distribution in the Tengchong geothermal area, China

Journal Article · Thu Jan 01 00:00:00 EST 1987 · Geothermics; (United States)

DOI:https://doi.org/10.1016/0375-6505(87)90065-4· OSTI ID:6060555

Meixiang, Z; Wei, T

In the active hydrothermal areas of Tengchong there is widespread evidence that hydrothermal minerals are deposited directly from the geothermal fluid or from water-rock interactions. X-ray powder diffraction, electron microprobe analyses and classical optical methods were used to identify these hydrothermal minerals. Sulfates (gypsum, alunite, alunogen, halotrichite, etc.), carbonates (calcite, trona, thermonatrite, etc.), clay minerals (kaolinite, illite-smectite mixed layer mineral, etc.) and silica minerals (opal, chalcedony, etc.) are the dominant phases. Native sulfur, pyrite, marcasite and aragonite are next in order of abundance. Some chabazite, analcime, pitchblende, coffinite, hematite, thenardite, rozenite, coquimbite, manganocalcite and rhodochrosite is also present. Although travertine and efflorescences, along with carbonates and simple sulfates, are widespread in the low-temperature hydrothermal areas, siliceous sinters and hydrothermal altered minerals, such as clay minerals, zeolites and efflorescences with complex sulfates containing Fe, Al, are only found in a few high-temperature hydrothermal areas, such as in the Hot Sea and the Ruidian hydrothermal areas. Most of the wall rock was intensely altered by geothermal fluid in the Hot Sea and Ruidian, zoning in the characteristic feature of the altered minerals within the Hot Sea. Pitchblende, coffinite, pyrite, marcasite and hematite, which are all of hydrothermal genesis, as well as the sulfate with Al and Fe, seem to be the result of water-rock interaction.

• Research Organization: Dept. of Geology, Peking Univ., Beijing
• OSTI ID: 6060555
• Journal Information: Geothermics; (United States), Vol. 16:2
• Country of Publication: United States
• Language: English

Related Subjects

15 GEOTHERMAL ENERGY
CARBONATES
ELECTRON MICROPROBE ANALYSIS
X-RAY DIFFRACTION
CHINA
GEOTHERMAL FIELDS
CLAYS
HYDROTHERMAL SYSTEMS
GEOCHEMICAL SURVEYS
SILICA
SULFATE MINERALS
ARAGONITE
GEOTHERMAL EXPLORATION
HYDROTHERMAL ALTERATION
MARCASITE
PYRITE
ROCK-FLUID INTERACTIONS
SULFUR
ALKALINE EARTH METAL COMPOUNDS
ASIA
CALCIUM CARBONATES
CALCIUM COMPOUNDS
CARBON COMPOUNDS
CARBONATE MINERALS
CHALCOGENIDES
CHEMICAL ANALYSIS
COHERENT SCATTERING
DIFFRACTION
ELEMENTS
ENERGY SYSTEMS
EXPLORATION
GEOTHERMAL SYSTEMS
IRON COMPOUNDS
IRON SULFIDES
MICROANALYSIS
MINERALS
NONMETALS
OXIDE MINERALS
OXIDES
OXYGEN COMPOUNDS
SCATTERING
SILICON COMPOUNDS
SILICON OXIDES
SULFIDE MINERALS
SULFIDES
SULFUR COMPOUNDS
SURVEYS
TRANSITION ELEMENT COMPOUNDS
152003* - Geothermal Data & Theory- Rock-Water-Gas Interactions