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M R Palmer - One of the best experts on this subject based on the ideXlab platform.
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Isotopic and geochemical investigation of a carbonatite-syenite-phonolite Diatreme, West Eifel (Germany)
2015Co-Authors: Teal R Riley, D K Bailey, Felicity E Lloyd, R. E. I-iarm~r, H. Lebsch, M R PalmerAbstract:The Rockeskyll complex in the north, central part of the Quaternary West Eifel volcanic field encapsulates an association of carbonatite, nephelinite and phonolite. The volcanic complex is dominated by three eruptive centres, which are distinct in their magma chemistry and their mode of emplacement. The Auf Dickel Diatreme forms one centre and has erupted the only known carbonatite in the West Eifel, along with a broad range of alkaline rock types. Extrusive carbonatitic volcanism is represented by spheroidal autoliths, which preserve an equilibrium assemblage. The Diatreme has also erupted xenoliths of calcite-bearing feldspathoidal syenite, phonolite and sanidine and clinopyroxene megacrysts, which are interpreted as fragments of a sub-volcanic complex. The carbonate phase of volcanism has several manifestations; extrusive lapilli, recrystallized ashes and calcite-bearing syenites, fragmented during Diatreme mplacement. A petrogenetic link between carbonatites and alkali mafic magmas is confirmed from Sr and Nd isotope systematics, and an upper mantle origin for the felsic rocks is suggested. The chemistry and mineralogy of mantle xenoliths erupted throughout the West Eifel indicate enrichment in those elements incompatible in the mantle. In addition, the evidence from trace element signatures and melts trapped as glasses support interaction between depleted mantle and small volume carbonate and felsic melts. This close association between carbonate and felsic melts in the mantle is mirrored in the surface eruptives of Auf Dickel and at numerous alkaline-carbonatite provinces worldwide
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isotopic and geochemical investigation of a carbonatite syenite phonolite Diatreme west eifel germany
Mineralogical Magazine, 1999Co-Authors: Teal R Riley, D K Bailey, R E Harmer, H Liebsch, Felicity E Lloyd, M R PalmerAbstract:The Rockeskyll complex in the north, central part of the Quaternary West Eifel volcanic field encapsulates an association of carbonatite, nephelinite and phonolite. The volcanic complex is dominated by three eruptive centres, which are distinct in their magma chemistry and their mode of emplacement. The Auf Dickel Diatreme forms one centre and has erupted the only known carbonatite in the West Eifel, along with a broad range of alkaline rock types. Extrusive carbonatitic volcanism is represented by spheroidal autoliths, which preserve an equilibrium assemblage. The Diatreme has also erupted xenoliths of calcite-bearing feldspathoidal syenite, phonolite and sanidine and clinopyroxene megacrysts, which are interpreted as fragments of a sub-volcanic complex. The carbonate phase of volcanism has several manifestations; extrusive lapilli, recrystallized ashes and calcite-bearing syenites, fragmented during Diatreme emplacement. A petrogenetic link between carbonatites and alkali mafic magmas is confirmed from Sr and Nd isotope systematics, and an upper mantle origin for the felsic rocks is suggested. The chemistry and mineralogy of mantle xenoliths erupted throughout the West Eifel indicate enrichment in those elements incompatible in the mantle. In addition, the evidence from trace element signatures and melts trapped as glasses support interaction between depleted mantle and small volume carbonate and felsic melts. This close association between carbonate and felsic melts in the mantle is mirrored in the surface eruptives of Auf Dickel and at numerous alkaline-carbonatite provinces worldwide.
Isaia Roberto - One of the best experts on this subject based on the ideXlab platform.
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Stratigraphy, structure, and volcano-tectonic evolution of Solfatara maar-Diatreme (Campi Flegrei, Italy)
'Geological Society of America', 2015Co-Authors: Isaia Roberto, Vitale Roberto, Di Giuseppe, Maria Giulia, Iannuzzi Enrico, Tramparulo, Francesco D'assisi, Troiano AntonioAbstract:This study focuses on the Solfatara volcano within Campi Flegrei, a volcanic eld located on the Tyrrhenian coast of southern Italy. Volcanism at the Campi Flegrei caldera has included phreatic to phreatomagmatic explosions and both magmatic (ranging from small scoria-producing events to those with Plinian columns) and effusive eruptions. These eruptions have formed tuff cones, tuff rings, minor scoria cones, and lava domes. A detailed stratigraphic, structural, and geo- physical study of the area indicates that the Solfatara volcano is a maar-Diatreme structure previously not recognized within the Campi Flegrei caldera. It is characterized by a crater cut into earlier volcanic deposits, a small rim of ejecta, and a deep structure (down to 2–3 km). This maar-Diatreme has allowed the gases and uids to ow up to the surface over a long time. A new geological map and cross sections show a complex architecture of different volcano-tectonic features including scoria cones, lavas, crypto- domes, feeder dikes, pipes, ring and regional faults, and explosive craters. Volcanological data were collected with the main aim of characterizing the eruptive activity in a lim- ited sector of the caldera. Fault and fracture analyses, using the scan line methodology, highlight the role of the main structures that accompanied the volcanic evolution within this sector of the Campi Flegrei caldera. To better constrain the subsurface structure of the Solfatara crater, electrical resistivity tomography investigations were integrated with the volcano-tectonic information. All data suggest that the Solfatara area is dominated by a maar-Diatreme evolution. Pres- ently, the Solfatara area shows widespread hydrothermal and fumarolic activity that is localized along the major faults. The results allow us to de ne a particular type of vol- canic activity in the recent past, in what is still considered today an area with a higher probability of opening new vents, particu- larly for possible phreatic activity.Published1485–15042V. Struttura e sistema di alimentazione dei vulcaniJCR Journa
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Stratigraphy, structure, and volcano-tectonic evolution of Solfatara maar-Diatreme (Campi Flegrei, Italy)
'Geological Society of America', 2015Co-Authors: Isaia Roberto, Di Giuseppe, Maria Giulia, Iannuzzi Enrico, Tramparulo, Francesco D'assisi, Vitale Stefano, Troiano TroianoAbstract:This study focuses on the Solfatara volcano within the Campi Flegrei, a volcanic field located in the Tyrrhenian coast of the southern Italy. Volcanism at Campi Flegrei caldera has included phreatic to phreatomagmatic explosions, and both magmatic (ranging from small scoria producing events to those with Plinian columns) and effusive eruptions. These eruptions have formed tuff cones, tuff rings, minor scoria cones and lava domes. A detailed stratigraphic, structural and geophysical study of the area indicates that the Solfatara volcano is a maar-Diatreme structure previously not recognized within the Campi Flegrei caldera. It is characterized by a crater cut into earlier volcanic deposits, a small rim of ejecta and a deep structure (down to 2-3 km). This maar-Diatreme has allowed to the gases and fluids to flow up to the surface over a long time. A new geological map and cross sections show a complex architecture of different volcano-tectonic features including scoria cones, lavas and cryptodomes, feeder dykes, pipes, ring and regional faults, and explosive craters. Volcanological data were collected with the main aim to characterize the eruptive activity in a limited sector of the caldera. Fault and fracture analyses, using the scan line methodology, highlight the role of the main structures that accompanied the volcanic evolution within this sector of the Campi Flegrei caldera. To better constrain the subsurface structure of the Solfatara crater, Electrical Resistivity Tomography investigations were integrated with the volcano-tectonic information. All data suggest that the Solfatara area is dominated by a maar-Diatreme evolution. Presently, the Solfatara area shows a widespread hydrothermal and fumarolic activity that is localized along the major faults. The results allow us to define a particular type of volcanic activity in the recent past in the area that is still considered today as one of the areas with a higher probability of opening new vents, particularly for possible phreatic activity
Troiano Antonio - One of the best experts on this subject based on the ideXlab platform.
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Stratigraphy, structure, and volcano-tectonic evolution of Solfatara maar-Diatreme (Campi Flegrei, Italy)
'Geological Society of America', 2015Co-Authors: Isaia Roberto, Vitale Roberto, Di Giuseppe, Maria Giulia, Iannuzzi Enrico, Tramparulo, Francesco D'assisi, Troiano AntonioAbstract:This study focuses on the Solfatara volcano within Campi Flegrei, a volcanic eld located on the Tyrrhenian coast of southern Italy. Volcanism at the Campi Flegrei caldera has included phreatic to phreatomagmatic explosions and both magmatic (ranging from small scoria-producing events to those with Plinian columns) and effusive eruptions. These eruptions have formed tuff cones, tuff rings, minor scoria cones, and lava domes. A detailed stratigraphic, structural, and geo- physical study of the area indicates that the Solfatara volcano is a maar-Diatreme structure previously not recognized within the Campi Flegrei caldera. It is characterized by a crater cut into earlier volcanic deposits, a small rim of ejecta, and a deep structure (down to 2–3 km). This maar-Diatreme has allowed the gases and uids to ow up to the surface over a long time. A new geological map and cross sections show a complex architecture of different volcano-tectonic features including scoria cones, lavas, crypto- domes, feeder dikes, pipes, ring and regional faults, and explosive craters. Volcanological data were collected with the main aim of characterizing the eruptive activity in a lim- ited sector of the caldera. Fault and fracture analyses, using the scan line methodology, highlight the role of the main structures that accompanied the volcanic evolution within this sector of the Campi Flegrei caldera. To better constrain the subsurface structure of the Solfatara crater, electrical resistivity tomography investigations were integrated with the volcano-tectonic information. All data suggest that the Solfatara area is dominated by a maar-Diatreme evolution. Pres- ently, the Solfatara area shows widespread hydrothermal and fumarolic activity that is localized along the major faults. The results allow us to de ne a particular type of vol- canic activity in the recent past, in what is still considered today an area with a higher probability of opening new vents, particu- larly for possible phreatic activity.Published1485–15042V. Struttura e sistema di alimentazione dei vulcaniJCR Journa
Troiano Troiano - One of the best experts on this subject based on the ideXlab platform.
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Stratigraphy, structure, and volcano-tectonic evolution of Solfatara maar-Diatreme (Campi Flegrei, Italy)
'Geological Society of America', 2015Co-Authors: Isaia Roberto, Di Giuseppe, Maria Giulia, Iannuzzi Enrico, Tramparulo, Francesco D'assisi, Vitale Stefano, Troiano TroianoAbstract:This study focuses on the Solfatara volcano within the Campi Flegrei, a volcanic field located in the Tyrrhenian coast of the southern Italy. Volcanism at Campi Flegrei caldera has included phreatic to phreatomagmatic explosions, and both magmatic (ranging from small scoria producing events to those with Plinian columns) and effusive eruptions. These eruptions have formed tuff cones, tuff rings, minor scoria cones and lava domes. A detailed stratigraphic, structural and geophysical study of the area indicates that the Solfatara volcano is a maar-Diatreme structure previously not recognized within the Campi Flegrei caldera. It is characterized by a crater cut into earlier volcanic deposits, a small rim of ejecta and a deep structure (down to 2-3 km). This maar-Diatreme has allowed to the gases and fluids to flow up to the surface over a long time. A new geological map and cross sections show a complex architecture of different volcano-tectonic features including scoria cones, lavas and cryptodomes, feeder dykes, pipes, ring and regional faults, and explosive craters. Volcanological data were collected with the main aim to characterize the eruptive activity in a limited sector of the caldera. Fault and fracture analyses, using the scan line methodology, highlight the role of the main structures that accompanied the volcanic evolution within this sector of the Campi Flegrei caldera. To better constrain the subsurface structure of the Solfatara crater, Electrical Resistivity Tomography investigations were integrated with the volcano-tectonic information. All data suggest that the Solfatara area is dominated by a maar-Diatreme evolution. Presently, the Solfatara area shows a widespread hydrothermal and fumarolic activity that is localized along the major faults. The results allow us to define a particular type of volcanic activity in the recent past in the area that is still considered today as one of the areas with a higher probability of opening new vents, particularly for possible phreatic activity
Diego M. Guido - One of the best experts on this subject based on the ideXlab platform.
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Intrusive hyaloclastite and peperitic breccias associated to sill and cryptodome emplacement on an Early Paleocene polymagmatic compound cone-dome volcanic complex from El Guanaco mine, Northern Chile
Journal of Volcanology and Geothermal Research, 2018Co-Authors: Gerardo N. Páez, C. Permuy Vidal, M. Galina, Lourdes López, S.m. Jovic, Diego M. GuidoAbstract:Abstract This work explores the textural characteristics, morphology and facies architecture of well-preserved Paleocene hyaloclastic and peperitic breccias associated with subvolcanic intrusions at El Guanaco gold mine (Northern Chile). The El Guanaco mine volcanic sequence is part of a polymagmatic compound cone-dome volcanic complex grouping several dacitic domes and maar-Diatremes, and subordinated subvolcanic intrusions of basaltic, andesitic and dacitic compositions. The Soledad-Penafiel Fault System is a first order regional structure controlling the location and style of the volcanism in the region. Three different intrusive bodies (Basaltic sills, Dacitic cryptodomes and Andesitic cryptodomes) were found to intrude into a wet and poorly consolidated pyroclastic sequence representing the upper portions of a maar-Diatreme. Consequently, extensive quench fragmentation and fluidization along their contacts occurred, leading to the formation of widespread breccia bodies enclosing a coherent nucleus. Differences in matrix composition allows to define two main breccias types: 1) poorly-sorted monomictic breccias (intrusive hyaloclastites) and 2) poorly-sorted tuff-matrix breccias (peperites). The observed facies architecture is interpreted as the result of the interplay of several factors, including: 1) magma viscosity, 2) the geometry of the intrusives, and 3) variations on the consolidation degree of the host rocks. Additionally, the overall geometry of each intrusive is interpreted to be controlled by the effective viscosity of the magmas along with the available magma volume at the time of the intrusions. The presence of three compositionally different subvolcanic bodies with intrusive hyaloclastite and peperite envelopes indicate, not only that all these intrusions occurred in a short period of time (probably less than 2–3 Ma), but also that the volcaniciclastic pile suffer little or none compaction nor consolidation during that time. The presence of three compositionally variated synvolcanic intrusives can be explained either by the presence of a zoned magmatic chamber feeding the volcanic complex, or more likely by the influence of the Soledad-Penafiel Fault Zone acting as a preferential pathway for different magma compositions/sources to rise to the surface.