{"id":{"repo_id":"vt","oai_identifier":"oai:vtechworks.lib.vt.edu:10919/74143"},"canonical_url":"https://search.dev.ndltd.org/etd/vt/oai:vtechworks.lib.vt.edu:10919/74143","repository":{"repo_id":"vt","name":"Virginia Tech","base_url":"https://vtechworks.lib.vt.edu/oai/request"},"display":{"title":"Calculation of temperature - oxygen fugacity tables for H₂-CO₂ gas mixtures at one atmosphere total pressure, and an investigation of the zoisite-clinozoisite transition","abstract":"Part I: Calculation of Temperature - Oxygen Fugacity Tables for H₂ - CO₂ Gas Mixtures at One Atmosphere Total Pressure. The initial CO₂ volumes yielding selected oxygen fugacities at specified temperatures have been computed for H₂ - CO₂ gas mixtures at one atmosphere total pressure. The calculations are based on the thermochemical data of the JANAF (1971) Tables for the species CO₂-H₂-H₂O-CO-O₂-CH₄ and are carried out using the Newton-Raphson method of successive approximation. The new tables replace older ones (Dienes, Nafziger, Ulmer and Woermann, 1974) in which the effects of CH₄ on the system were treated only in an approximate manner. Part II: An Investigation of the Zoisite - Clinozoisite Transition Available data on natural coexisting zoisite - clinozoisite (Ca₂Al<sub>3-x</sub>Fe<sub>x</sub>[Si₂O₇][SiO₄]O(OH) with x ≤ 0.33) assemblages imply that the two phases are related by a solid solution transition loop, with zoisite being the low-iron, high-temperature, high-pressure phase. Reversibility experiments at 6500 bars constrain the iron-free equilibrium clinozoisite zoisite to lie below 407°C. Electron microprobe and single crystal x-ray diffraction studies of epitactically related zoisite-clinozoisite crystals grown from seeded mixtures of anorthite, calcite, hematite and silica glass at 6500 bars and 650°C are shown to bracket the transition loop between Pistacite 3.2 (Ca₂Al<sub>2.90</sub>Fe<sub>0.10</sub>Si₃O₁₂(OH)) and Pistacite 12.6 (Ca₂Al<sub>2.62</sub>Fe<sub>0.38</sub>Si₃O₁₂(OH)). Experimental techniques used in this investigation, which focus on detalied analysis of single crystals, offer promise as a means for determining equilibrium phase relations of epidotes and other frequently zoned mineral groups.","abstract_html":"Part I: Calculation of Temperature - Oxygen Fugacity Tables for H₂ - CO₂ Gas Mixtures at One Atmosphere Total Pressure. The initial CO₂ volumes yielding selected oxygen fugacities at specified temperatures have been computed for H₂ - CO₂ gas mixtures at one atmosphere total pressure. The calculations are based on the thermochemical data of the JANAF (1971) Tables for the species CO₂-H₂-H₂O-CO-O₂-CH₄ and are carried out using the Newton-Raphson method of successive approximation. The new tables replace older ones (Dienes, Nafziger, Ulmer and Woermann, 1974) in which the effects of CH₄ on the system were treated only in an approximate manner. Part II: An Investigation of the Zoisite - Clinozoisite Transition Available data on natural coexisting zoisite - clinozoisite (Ca₂Al&lt;sub&gt;3-x&lt;/sub&gt;Fe&lt;sub&gt;x&lt;/sub&gt;[Si₂O₇][SiO₄]O(OH) with x ≤ 0.33) assemblages imply that the two phases are related by a solid solution transition loop, with zoisite being the low-iron, high-temperature, high-pressure phase. Reversibility experiments at 6500 bars constrain the iron-free equilibrium clinozoisite zoisite to lie below 407°C. Electron microprobe and single crystal x-ray diffraction studies of epitactically related zoisite-clinozoisite crystals grown from seeded mixtures of anorthite, calcite, hematite and silica glass at 6500 bars and 650°C are shown to bracket the transition loop between Pistacite 3.2 (Ca₂Al&lt;sub&gt;2.90&lt;/sub&gt;Fe&lt;sub&gt;0.10&lt;/sub&gt;Si₃O₁₂(OH)) and Pistacite 12.6 (Ca₂Al&lt;sub&gt;2.62&lt;/sub&gt;Fe&lt;sub&gt;0.38&lt;/sub&gt;Si₃O₁₂(OH)). Experimental techniques used in this investigation, which focus on detalied analysis of single crystals, offer promise as a means for determining equilibrium phase relations of epidotes and other frequently zoned mineral groups.","abstract_has_math":false,"creators":["Prunier, Arthur R."],"institution":"Virginia Polytechnic Institute and State University","degree_name":"Master of Science","degree_level":"masters","degree_discipline":"Geological Sciences","degree_department":"Geological Sciences","school":null,"contributors":[],"advisors":[],"committee_chairs":[],"committee_members":[],"year":1978,"date_issued":"1978","date_published":"1978","updated_at":"2026-07-22T22:19:47Z","subjects":[],"languages":["en"],"rights":["In Copyright"],"rights_urls":["http://rightsstatements.org/vocab/InC/1.0/"],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/10919/74143","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.department","label":"Department","values":["Geological Sciences"]},{"key":"dc:creator","label":"Author","values":["Prunier, Arthur R."]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2017-01-10T20:35:13Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2017-01-10T20:35:13Z"]},{"key":"dc:date.issued","label":"Date","values":["1978"]},{"key":"dc:publisher","label":"Institution","values":["Virginia Polytechnic Institute and State University"]},{"key":"dc:type","label":"Dc Type","values":["Thesis"]},{"key":"dc:type.dcmitype","label":"Dc Type Dcmitype","values":["Text"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Geological Sciences"]},{"key":"thesis:degree_level","label":"Degree Level","values":["masters"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Master of Science"]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["Virginia Polytechnic Institute and State University"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["en"]},{"key":"dc:rights","label":"Dc Rights","values":["In Copyright"]},{"key":"dc:rights.uri","label":"Rights URI","values":["http://rightsstatements.org/vocab/InC/1.0/"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["http://hdl.handle.net/10919/74143"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["Part I: Calculation of Temperature - Oxygen Fugacity Tables for H₂ - CO₂ Gas Mixtures at One Atmosphere Total Pressure. The initial CO₂ volumes yielding selected oxygen fugacities at specified temperatures have been computed for H₂ - CO₂ gas mixtures at one atmosphere total pressure. The calculations are based on the thermochemical data of the JANAF (1971) Tables for the species CO₂-H₂-H₂O-CO-O₂-CH₄ and are carried out using the Newton-Raphson method of successive approximation. The new tables replace older ones (Dienes, Nafziger, Ulmer and Woermann, 1974) in which the effects of CH₄ on the system were treated only in an approximate manner. Part II: An Investigation of the Zoisite - Clinozoisite Transition Available data on natural coexisting zoisite - clinozoisite (Ca₂Al<sub>3-x</sub>Fe<sub>x</sub>[Si₂O₇][SiO₄]O(OH) with x ≤ 0.33) assemblages imply that the two phases are related by a solid solution transition loop, with zoisite being the low-iron, high-temperature, high-pressure phase. Reversibility experiments at 6500 bars constrain the iron-free equilibrium clinozoisite zoisite to lie below 407°C. Electron microprobe and single crystal x-ray diffraction studies of epitactically related zoisite-clinozoisite crystals grown from seeded mixtures of anorthite, calcite, hematite and silica glass at 6500 bars and 650°C are shown to bracket the transition loop between Pistacite 3.2 (Ca₂Al<sub>2.90</sub>Fe<sub>0.10</sub>Si₃O₁₂(OH)) and Pistacite 12.6 (Ca₂Al<sub>2.62</sub>Fe<sub>0.38</sub>Si₃O₁₂(OH)). Experimental techniques used in this investigation, which focus on detalied analysis of single crystals, offer promise as a means for determining equilibrium phase relations of epidotes and other frequently zoned mineral groups."]},{"key":"dc:description.degree","label":"Dc Description Degree","values":["Master of Science"]},{"key":"dc:format.mimetype","label":"Dc Format Mimetype","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["Calculation of temperature - oxygen fugacity tables for H₂-CO₂ gas mixtures at one atmosphere total pressure, and an investigation of the zoisite-clinozoisite transition"]}]}],"canonical_facts":{"dc:contributor.department":["Geological Sciences"],"dc:creator":["Prunier, Arthur R."],"dc:date.accessioned":["2017-01-10T20:35:13Z"],"dc:date.available":["2017-01-10T20:35:13Z"],"dc:date.issued":["1978"],"dc:description.abstract":["Part I: Calculation of Temperature - Oxygen Fugacity Tables for H₂ - CO₂ Gas Mixtures at One Atmosphere Total Pressure. The initial CO₂ volumes yielding selected oxygen fugacities at specified temperatures have been computed for H₂ - CO₂ gas mixtures at one atmosphere total pressure. The calculations are based on the thermochemical data of the JANAF (1971) Tables for the species CO₂-H₂-H₂O-CO-O₂-CH₄ and are carried out using the Newton-Raphson method of successive approximation. The new tables replace older ones (Dienes, Nafziger, Ulmer and Woermann, 1974) in which the effects of CH₄ on the system were treated only in an approximate manner. Part II: An Investigation of the Zoisite - Clinozoisite Transition Available data on natural coexisting zoisite - clinozoisite (Ca₂Al<sub>3-x</sub>Fe<sub>x</sub>[Si₂O₇][SiO₄]O(OH) with x ≤ 0.33) assemblages imply that the two phases are related by a solid solution transition loop, with zoisite being the low-iron, high-temperature, high-pressure phase. Reversibility experiments at 6500 bars constrain the iron-free equilibrium clinozoisite zoisite to lie below 407°C. Electron microprobe and single crystal x-ray diffraction studies of epitactically related zoisite-clinozoisite crystals grown from seeded mixtures of anorthite, calcite, hematite and silica glass at 6500 bars and 650°C are shown to bracket the transition loop between Pistacite 3.2 (Ca₂Al<sub>2.90</sub>Fe<sub>0.10</sub>Si₃O₁₂(OH)) and Pistacite 12.6 (Ca₂Al<sub>2.62</sub>Fe<sub>0.38</sub>Si₃O₁₂(OH)). Experimental techniques used in this investigation, which focus on detalied analysis of single crystals, offer promise as a means for determining equilibrium phase relations of epidotes and other frequently zoned mineral groups."],"dc:description.degree":["Master of Science"],"dc:format.mimetype":["application/pdf"],"dc:identifier.uri":["http://hdl.handle.net/10919/74143"],"dc:language.iso":["en"],"dc:publisher":["Virginia Polytechnic Institute and State University"],"dc:rights":["In Copyright"],"dc:rights.uri":["http://rightsstatements.org/vocab/InC/1.0/"],"dc:title":["Calculation of temperature - oxygen fugacity tables for H₂-CO₂ gas mixtures at one atmosphere total pressure, and an investigation of the zoisite-clinozoisite transition"],"dc:type":["Thesis"],"dc:type.dcmitype":["Text"],"thesis:degree_discipline":["Geological Sciences"],"thesis:degree_level":["masters"],"thesis:degree_name":["Master of Science"],"thesis:institution_name":["Virginia Polytechnic Institute and State University"]},"updated_at":"2026-07-22T22:19:47Z"}