Characterization of the dissolution of hornblende with application to natural waters

Persistent Link:
http://hdl.handle.net/10150/276942
Title:
Characterization of the dissolution of hornblende with application to natural waters
Author:
Hopkins, Emily Elaine, 1964-
Issue Date:
1989
Publisher:
The University of Arizona.
Rights:
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
Abstract:
Dissolution rates of hornblende and tremolite were studied in constant pH batch experiments over the pH range 4-6, in order to understand the acid neutralizing role of hornblende in watersheds with low alkalinity. Hornblende and tremolite exhibit linear dissolution kinetics within one or two days after the onset of weathering. During the first 80-100 hours of weathering, base cations are released preferentially to silica in both minerals. During this period a leached surface layer similar in structure to the original material, but altered in composition is believed to be formed. Release rates of Si, Ca, Na, and Mg from hornblende exhibit weak fractional dependence on pH: d[Mg] /dt = k₁[H⁺] 0.13, d[Ca] /dt = k₁[H⁺] 0.065, d[Na] /dt = k₁[H⁺] 0.17, and d[Si] /dt = k₁[H⁺] 0.045. As a result, it is believed that, for large and transient influxes of acidified water, hornblende is not an important pH buffer. Because of rapid dissolution rates, however, hornblende could be an important source of acid neutralizing capacity.
Type:
text; Thesis-Reproduction (electronic)
Keywords:
Hornblende -- Solubility.; Water chemistry.; Weathering.; Water-rock interaction.
Degree Name:
M.S.
Degree Level:
masters
Degree Program:
Graduate College; Hydrology and Water Resources
Degree Grantor:
University of Arizona
Advisor:
Conklin, Martha

Full metadata record

DC FieldValue Language
dc.language.isoen_USen_US
dc.titleCharacterization of the dissolution of hornblende with application to natural watersen_US
dc.creatorHopkins, Emily Elaine, 1964-en_US
dc.contributor.authorHopkins, Emily Elaine, 1964-en_US
dc.date.issued1989en_US
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.description.abstractDissolution rates of hornblende and tremolite were studied in constant pH batch experiments over the pH range 4-6, in order to understand the acid neutralizing role of hornblende in watersheds with low alkalinity. Hornblende and tremolite exhibit linear dissolution kinetics within one or two days after the onset of weathering. During the first 80-100 hours of weathering, base cations are released preferentially to silica in both minerals. During this period a leached surface layer similar in structure to the original material, but altered in composition is believed to be formed. Release rates of Si, Ca, Na, and Mg from hornblende exhibit weak fractional dependence on pH: d[Mg] /dt = k₁[H⁺] 0.13, d[Ca] /dt = k₁[H⁺] 0.065, d[Na] /dt = k₁[H⁺] 0.17, and d[Si] /dt = k₁[H⁺] 0.045. As a result, it is believed that, for large and transient influxes of acidified water, hornblende is not an important pH buffer. Because of rapid dissolution rates, however, hornblende could be an important source of acid neutralizing capacity.en_US
dc.typetexten_US
dc.typeThesis-Reproduction (electronic)en_US
dc.subjectHornblende -- Solubility.en_US
dc.subjectWater chemistry.en_US
dc.subjectWeathering.en_US
dc.subjectWater-rock interaction.en_US
thesis.degree.nameM.S.en_US
thesis.degree.levelmastersen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.disciplineHydrology and Water Resourcesen_US
thesis.degree.grantorUniversity of Arizonaen_US
dc.contributor.advisorConklin, Marthaen_US
dc.identifier.proquest1336344en_US
dc.identifier.oclc22461850en_US
dc.identifier.bibrecord.b17435687en_US
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