{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/113072"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/113072","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"Ghost granophyre: A new texture with implications for plagiogranite differentiation and Ti-in-Quartz thermometry","abstract":"Understanding the origins of the Earth and its crust is a fundamental goal of the geosciences and the construction of the oceanic crust comprises half the story of our planet’s unique bimodal crustal distribution. The oceanic crust is overwhelmingly mafic with the exception of plagiogranites, which can represent relatively extensive volumes of silicic material locally and are common at the gabbro-sheeted dike contact. The origin of plagiogranites is poorly understood. Granophyre, which is also poorly understood, is a common texture in plagiogranites as well as other granitoids. I present observations of “Ghost Granophyre,” a new cathodoluminescence texture of granophyre in Troodos quartz crystals which I argue results from pseudomorphic replacement of the albite in granophyre by quartz. In combination these observations point toward both a new model for plagiogranite differentiation via reactive flow of recently described low temperature silicate liquids which span the magmatic-hydrothermal transition, as well as a way to make granophyre without the involvement of a silicate melt. These findings expand the definition of the term granophyre, which still sees heavy usage in the petrology literature as being synonymous with rapid crystallization of a silicate melt, to include granophyre formed through fluid-crystal interactions that are hundreds of degrees subsolidus with respect to traditional silicate melts. This work also brings into question the applicability of the Ti-in-Quartz geothermometer—a powerful and widely used tool for estimating crystallization temperatures in silicic igneous lithologies generally—to situations like Troodos where pervasive mineralogical reactions occur and drive bulk compositional differentiation to silicic lithologies. If a near-ubiquitous “igneous” texture like granophyre can be created without a silicate melt, then long-held assumptions regarding other “igneous” textures should be reexamined.","abstract_html":"Understanding the origins of the Earth and its crust is a fundamental goal of the geosciences and the construction of the oceanic crust comprises half the story of our planet’s unique bimodal crustal distribution. The oceanic crust is overwhelmingly mafic with the exception of plagiogranites, which can represent relatively extensive volumes of silicic material locally and are common at the gabbro-sheeted dike contact. The origin of plagiogranites is poorly understood. Granophyre, which is also poorly understood, is a common texture in plagiogranites as well as other granitoids. I present observations of “Ghost Granophyre,” a new cathodoluminescence texture of granophyre in Troodos quartz crystals which I argue results from pseudomorphic replacement of the albite in granophyre by quartz. In combination these observations point toward both a new model for plagiogranite differentiation via reactive flow of recently described low temperature silicate liquids which span the magmatic-hydrothermal transition, as well as a way to make granophyre without the involvement of a silicate melt. These findings expand the definition of the term granophyre, which still sees heavy usage in the petrology literature as being synonymous with rapid crystallization of a silicate melt, to include granophyre formed through fluid-crystal interactions that are hundreds of degrees subsolidus with respect to traditional silicate melts. This work also brings into question the applicability of the Ti-in-Quartz geothermometer—a powerful and widely used tool for estimating crystallization temperatures in silicic igneous lithologies generally—to situations like Troodos where pervasive mineralogical reactions occur and drive bulk compositional differentiation to silicic lithologies. If a near-ubiquitous “igneous” texture like granophyre can be created without a silicate melt, then long-held assumptions regarding other “igneous” textures should be reexamined.","abstract_has_math":false,"creators":["Campe, Christopher Edward"],"institution":"University of Illinois at Urbana-Champaign","degree_name":"M.S.","degree_level":"Thesis","degree_discipline":"Geology","degree_department":null,"school":null,"contributors":["Lundstrom, Craig C"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2022,"date_issued":"2022-01-12T21:46:55Z","date_published":"2022-01-12T21:46:55Z","updated_at":"2026-07-22T22:24:53Z","subjects":["texture","chlorite","granophyre","ghost granophyre","plagiogranites","plagiogranite","quartz","subsolidus","hydrothermal","fluid","greenschist","alteration","crust","cathodoluminescence","CL","geothermometer","geothermometry","thermometer","thermometry","granitoid","granitoids","differentiation","igneous"],"languages":["en"],"rights":["Copyright 2021 Christopher E. Campe"],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/2142/113072","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Lundstrom, Craig C"]},{"key":"dc:creator","label":"Author","values":["Campe, Christopher Edward"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2022-01-12T21:46:55Z","2021-07-21","2021-08"]},{"key":"dc:type","label":"Dc Type","values":["text","Thesis"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Geology"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Thesis"]},{"key":"thesis:degree_name","label":"Degree Name","values":["M.S."]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["University of Illinois at Urbana-Champaign"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["texture","chlorite","granophyre","ghost granophyre","plagiogranites","plagiogranite","quartz","subsolidus","hydrothermal","fluid","greenschist","alteration","crust","cathodoluminescence","CL","geothermometer","geothermometry","thermometer","thermometry","granitoid","granitoids","differentiation","igneous"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["en"]},{"key":"dc:rights","label":"Dc Rights","values":["Copyright 2021 Christopher E. Campe"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["http://hdl.handle.net/2142/113072"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Understanding the origins of the Earth and its crust is a fundamental goal of the geosciences and the construction of the oceanic crust comprises half the story of our planet’s unique bimodal crustal distribution. The oceanic crust is overwhelmingly mafic with the exception of plagiogranites, which can represent relatively extensive volumes of silicic material locally and are common at the gabbro-sheeted dike contact. The origin of plagiogranites is poorly understood. Granophyre, which is also poorly understood, is a common texture in plagiogranites as well as other granitoids. I present observations of “Ghost Granophyre,” a new cathodoluminescence texture of granophyre in Troodos quartz crystals which I argue results from pseudomorphic replacement of the albite in granophyre by quartz. In combination these observations point toward both a new model for plagiogranite differentiation via reactive flow of recently described low temperature silicate liquids which span the magmatic-hydrothermal transition, as well as a way to make granophyre without the involvement of a silicate melt. These findings expand the definition of the term granophyre, which still sees heavy usage in the petrology literature as being synonymous with rapid crystallization of a silicate melt, to include granophyre formed through fluid-crystal interactions that are hundreds of degrees subsolidus with respect to traditional silicate melts. This work also brings into question the applicability of the Ti-in-Quartz geothermometer—a powerful and widely used tool for estimating crystallization temperatures in silicic igneous lithologies generally—to situations like Troodos where pervasive mineralogical reactions occur and drive bulk compositional differentiation to silicic lithologies. If a near-ubiquitous “igneous” texture like granophyre can be created without a silicate melt, then long-held assumptions regarding other “igneous” textures should be reexamined.","Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2022-01-12 without embargo terms","The student, Christopher Campe, accepted the attached license on 2021-07-19 at 13:57.","The student, Christopher Campe, submitted this Thesis for approval on 2021-07-19 at 15:07.","This Thesis was approved for publication on 2021-07-21 at 09:03.","DSpace SAF Submission Ingestion Package generated from Vireo submission #17008 on 2022-01-12 at 12:46:17","Made available in DSpace on 2022-01-12T21:46:55Z (GMT). No. of bitstreams: 2 CAMPE-THESIS-2021.pdf: 7095228 bytes, checksum: 2145407ff605b3baccb4bef4c85a39fa (MD5) LICENSE.txt: 4208 bytes, checksum: 4b80a3b4d6efc05761b3fc13590363bf (MD5) Previous issue date: 2021-07-21"]},{"key":"dc:format","label":"Dc Format","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["Ghost granophyre: A new texture with implications for plagiogranite differentiation and Ti-in-Quartz thermometry"]}]}],"canonical_facts":{"dc:contributor":["Lundstrom, Craig C"],"dc:creator":["Campe, Christopher Edward"],"dc:date":["2022-01-12T21:46:55Z","2021-07-21","2021-08"],"dc:description":["Understanding the origins of the Earth and its crust is a fundamental goal of the geosciences and the construction of the oceanic crust comprises half the story of our planet’s unique bimodal crustal distribution. The oceanic crust is overwhelmingly mafic with the exception of plagiogranites, which can represent relatively extensive volumes of silicic material locally and are common at the gabbro-sheeted dike contact. The origin of plagiogranites is poorly understood. Granophyre, which is also poorly understood, is a common texture in plagiogranites as well as other granitoids. I present observations of “Ghost Granophyre,” a new cathodoluminescence texture of granophyre in Troodos quartz crystals which I argue results from pseudomorphic replacement of the albite in granophyre by quartz. In combination these observations point toward both a new model for plagiogranite differentiation via reactive flow of recently described low temperature silicate liquids which span the magmatic-hydrothermal transition, as well as a way to make granophyre without the involvement of a silicate melt. These findings expand the definition of the term granophyre, which still sees heavy usage in the petrology literature as being synonymous with rapid crystallization of a silicate melt, to include granophyre formed through fluid-crystal interactions that are hundreds of degrees subsolidus with respect to traditional silicate melts. This work also brings into question the applicability of the Ti-in-Quartz geothermometer—a powerful and widely used tool for estimating crystallization temperatures in silicic igneous lithologies generally—to situations like Troodos where pervasive mineralogical reactions occur and drive bulk compositional differentiation to silicic lithologies. If a near-ubiquitous “igneous” texture like granophyre can be created without a silicate melt, then long-held assumptions regarding other “igneous” textures should be reexamined.","Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2022-01-12 without embargo terms","The student, Christopher Campe, accepted the attached license on 2021-07-19 at 13:57.","The student, Christopher Campe, submitted this Thesis for approval on 2021-07-19 at 15:07.","This Thesis was approved for publication on 2021-07-21 at 09:03.","DSpace SAF Submission Ingestion Package generated from Vireo submission #17008 on 2022-01-12 at 12:46:17","Made available in DSpace on 2022-01-12T21:46:55Z (GMT). No. of bitstreams: 2 CAMPE-THESIS-2021.pdf: 7095228 bytes, checksum: 2145407ff605b3baccb4bef4c85a39fa (MD5) LICENSE.txt: 4208 bytes, checksum: 4b80a3b4d6efc05761b3fc13590363bf (MD5) Previous issue date: 2021-07-21"],"dc:format":["application/pdf"],"dc:identifier":["http://hdl.handle.net/2142/113072"],"dc:language":["en"],"dc:rights":["Copyright 2021 Christopher E. Campe"],"dc:subject":["texture","chlorite","granophyre","ghost granophyre","plagiogranites","plagiogranite","quartz","subsolidus","hydrothermal","fluid","greenschist","alteration","crust","cathodoluminescence","CL","geothermometer","geothermometry","thermometer","thermometry","granitoid","granitoids","differentiation","igneous"],"dc:title":["Ghost granophyre: A new texture with implications for plagiogranite differentiation and Ti-in-Quartz thermometry"],"dc:type":["text","Thesis"],"thesis:degree_discipline":["Geology"],"thesis:degree_level":["Thesis"],"thesis:degree_name":["M.S."],"thesis:institution_name":["University of Illinois at Urbana-Champaign"]},"updated_at":"2026-07-22T22:24:53Z"}