The Ohaki-Broadlands hydrothermal area, New Zealand; mineralogy and related geochemistry

Clicks: 2
ID: 292597
1970
Free PDF
Article Quality & Performance Metrics
Overall Quality
Not rated
Combines reader engagement with the AI quality analysis. This article has not been analysed, so there is no overall score — reader engagement is measured and shown alongside.
AI Quality Assessment
Not analyzed
Readership in this journal
Emerging

Ranked #679 of 8,486 articles by views in american journal of science

Most read Least read

Bar heights use a square-root scale. Only the 120 most-read articles are drawn; the journal has 8,486 in total.

Mint this article as an NFT
Not yet minted

Create a permanent, verifiable on-chain record of this article on the Scimatic Network. The NFT is held in your Journament account, and you can withdraw it to your own wallet at any time.

5 SUSD one-off · no wallet required
Sign in to mint
Abstract
Deep drilling in the Ohaki-Broadlands geothermal area with mineralogical examination of hydrothermally altered volcanic rocks at levels down to 7000 ft (2134 m) and the chemical analysis of coexisting fluids, shows that hydrothermal mineral alteration at temperatures of 230 to 290 degrees at deep levels in permeable rocks tends to an equilibrium assemblage of K-mica, K-feldspar, albite, chlorite, calcite, and quartz (and occasionally wairakite). The deep waters are dilute (ca. 1200 ppm Cl) chloride-bicarbonate solutions containing appreciable carbon dioxide (m CO2 = 0-15). Individual minerals and their occurrences are discussed briefly, and stability diagrams are developed to correlate observed rock alteration mineralogy with water chemistry. Changes in water composition caused by boiling off steam and CO 2 can be related to changes in mineral assemblages, such as calcite precipitation and adularia and epidote formation. Variations in mineralogy are discussed in terms of temperature, permeability, water composition, and carbon dioxide concentrations, and a comparison is made with alteration at Wairakei where the carbon dioxide concentration is lower. Pyrite, pyrrhotite, chalcopyrite, sphalerite, and galena occur at depth in some Broadlands altered rocks and are mentioned briefly.
Reference Key
openalex_W2325948779 Use this key to autocite in the manuscript while using SciMatic Manuscript Manager or Thesis Manager
Authors P. R. L. Browne, A. J. Ellis
Journal american journal of science
Year 1970
DOI
10.2475/ajs.269.2.97
URL
https://doi.org/10.2475/ajs.269.2.97
Keywords Keywords not found

Citations

No citations found. To add a citation, contact the admin at info@scimatic.org

Comments

No comments yet. Be the first to comment on this article.