{"id":{"repo_id":"birmingham","oai_identifier":"oai:etheses.bham.ac.uk:798"},"canonical_url":"https://search.dev.ndltd.org/etd/birmingham/oai:etheses.bham.ac.uk:798","repository":{"repo_id":"birmingham","name":"University of Birmingham","base_url":"https://etheses.bham.ac.uk/cgi/oai2"},"display":{"title":"Linking sill morphology to emplacement mechanisms","abstract":"Mafic sill complexes are increasingly being shown to play a major role in the movement of magma around the upper crust in volcanic terranes and to have a role in mass extinction events in Earth history. Most of the current models of sill emplacement assume that brittle fracture operates at all points of sill emplacement. Within this thesis, a series of observations are presented from sheet intrusions in South Africa, USA and the UK showing that in certain situations, dependent on host rock lithology, the propagation of magma through normal brittle fracture can cease. In this circumstance a prevalent fluid/fluid or fluid/ductile relationship between host rock and intruding magma is often developed. Once this occurs, the evolution of a given sheet intrusion becomes distinctly different from that produced by normal brittle fracture alone. The break down in brittle fracture often leads to the development of magma fingers, which accelerate ahead of the main sheet of magma. It is important to note that it is ultimately the host rock lithology and its coupled response to intrusion of magma that dictates the ongoing evolution of the morphology of sheet intrusions in high-level magmatic systems.","abstract_html":"Mafic sill complexes are increasingly being shown to play a major role in the movement of magma around the upper crust in volcanic terranes and to have a role in mass extinction events in Earth history. Most of the current models of sill emplacement assume that brittle fracture operates at all points of sill emplacement. Within this thesis, a series of observations are presented from sheet intrusions in South Africa, USA and the UK showing that in certain situations, dependent on host rock lithology, the propagation of magma through normal brittle fracture can cease. In this circumstance a prevalent fluid/fluid or fluid/ductile relationship between host rock and intruding magma is often developed. Once this occurs, the evolution of a given sheet intrusion becomes distinctly different from that produced by normal brittle fracture alone. The break down in brittle fracture often leads to the development of magma fingers, which accelerate ahead of the main sheet of magma. It is important to note that it is ultimately the host rock lithology and its coupled response to intrusion of magma that dictates the ongoing evolution of the morphology of sheet intrusions in high-level magmatic systems.","abstract_has_math":false,"creators":["Schofield, Nick"],"institution":"University of Birmingham","degree_name":"d_ph","degree_level":"d_ph","degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2009,"date_issued":"2009-12","date_published":"2009-12","updated_at":"2026-07-24T01:11:10Z","subjects":["QE Geology"],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":null,"outbound_label":null,"outbound_source":null},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.sponsor","label":"Sponsor","values":["nerc"]},{"key":"dc:creator","label":"Author","values":["Schofield, Nick"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2009-12"]},{"key":"dc:date.issued","label":"Date","values":["2009-12"]},{"key":"dc:publisher.department","label":"Dc Publisher Department","values":["College of Life & Environmental Sciences","School of Geography, Earth and Environmental Sciences"]},{"key":"dc:publisher.institution","label":"Dc Publisher Institution","values":["University of Birmingham"]},{"key":"dc:relation.isreferencedby","label":"Dc Relation Isreferencedby","values":["http://etheses.bham.ac.uk//id/eprint/798/"]},{"key":"dc:type","label":"Dc Type","values":["Thesis"]},{"key":"dc:type.qualificationlevel","label":"Dc Type Qualificationlevel","values":["d_ph"]},{"key":"dc:type.qualificationname","label":"Dc Type Qualificationname","values":["d_ph"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["QE Geology"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["http://etheses.bham.ac.uk//id/eprint/798/2/Schofield09PhD1.pdf","http://etheses.bham.ac.uk//id/eprint/798/3/Schofield09PhD2.pdf","http://etheses.bham.ac.uk//id/eprint/798/10/Decl_IS_Schofield09PhD.pdf"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["Mafic sill complexes are increasingly being shown to play a major role in the movement of magma around the upper crust in volcanic terranes and to have a role in mass extinction events in Earth history. Most of the current models of sill emplacement assume that brittle fracture operates at all points of sill emplacement. Within this thesis, a series of observations are presented from sheet intrusions in South Africa, USA and the UK showing that in certain situations, dependent on host rock lithology, the propagation of magma through normal brittle fracture can cease. In this circumstance a prevalent fluid/fluid or fluid/ductile relationship between host rock and intruding magma is often developed. Once this occurs, the evolution of a given sheet intrusion becomes distinctly different from that produced by normal brittle fracture alone. The break down in brittle fracture often leads to the development of magma fingers, which accelerate ahead of the main sheet of magma. It is important to note that it is ultimately the host rock lithology and its coupled response to intrusion of magma that dictates the ongoing evolution of the morphology of sheet intrusions in high-level magmatic systems."]},{"key":"dc:format","label":"Dc Format","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["Linking sill morphology to emplacement mechanisms"]}]}],"canonical_facts":{"dc:contributor.sponsor":["nerc"],"dc:creator":["Schofield, Nick"],"dc:date":["2009-12"],"dc:date.issued":["2009-12"],"dc:description.abstract":["Mafic sill complexes are increasingly being shown to play a major role in the movement of magma around the upper crust in volcanic terranes and to have a role in mass extinction events in Earth history. Most of the current models of sill emplacement assume that brittle fracture operates at all points of sill emplacement. Within this thesis, a series of observations are presented from sheet intrusions in South Africa, USA and the UK showing that in certain situations, dependent on host rock lithology, the propagation of magma through normal brittle fracture can cease. In this circumstance a prevalent fluid/fluid or fluid/ductile relationship between host rock and intruding magma is often developed. Once this occurs, the evolution of a given sheet intrusion becomes distinctly different from that produced by normal brittle fracture alone. The break down in brittle fracture often leads to the development of magma fingers, which accelerate ahead of the main sheet of magma. It is important to note that it is ultimately the host rock lithology and its coupled response to intrusion of magma that dictates the ongoing evolution of the morphology of sheet intrusions in high-level magmatic systems."],"dc:format":["application/pdf"],"dc:identifier.uri":["http://etheses.bham.ac.uk//id/eprint/798/2/Schofield09PhD1.pdf","http://etheses.bham.ac.uk//id/eprint/798/3/Schofield09PhD2.pdf","http://etheses.bham.ac.uk//id/eprint/798/10/Decl_IS_Schofield09PhD.pdf"],"dc:publisher.department":["College of Life & Environmental Sciences","School of Geography, Earth and Environmental Sciences"],"dc:publisher.institution":["University of Birmingham"],"dc:relation.isreferencedby":["http://etheses.bham.ac.uk//id/eprint/798/"],"dc:subject":["QE Geology"],"dc:title":["Linking sill morphology to emplacement mechanisms"],"dc:type":["Thesis"],"dc:type.qualificationlevel":["d_ph"],"dc:type.qualificationname":["d_ph"]},"updated_at":"2026-07-24T01:11:10Z"}