Geophysical Identification and Characterization of Mafic-Ultramafic Intrusions in Plume Centre Regions
Gravity and magnetic data from the EGM2008 and EMAG2 datasets are used for a global study of geophysical anomalies in LIP plume centre regions with the goal of identifying mafic-ultramafic intrusions linked to those LIPs. Geophysical anomalies within eighteen LIPs are investigated. Four of these LIP...
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| Format: | Thesis |
| Language: | unknown |
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2016
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| Online Access: | https://curve.carleton.ca/677dc33a-6e7b-4d62-83c5-d84cc44225f5 http://catalogue.library.carleton.ca/record=b3859492 https://doi.org/10.22215/etd/2016-11233 |
| Summary: | Gravity and magnetic data from the EGM2008 and EMAG2 datasets are used for a global study of geophysical anomalies in LIP plume centre regions with the goal of identifying mafic-ultramafic intrusions linked to those LIPs. Geophysical anomalies within eighteen LIPs are investigated. Four of these LIPs are selected for detailed modelling: the Mackenzie, High-Arctic, Kunene-Kibaran, and Deccan LIPs. Modelling supports that these anomalies are produced by large (radius >30 km) and generally deep-seated crustal intrusions, with densities consistent with mafic-ultramafic rock and magnetic susceptibilities consistent with serpentinized ultramafic rock. Modelling also indicates that these values remain consistent within a LIP, particularly regarding density and depth. Lastly, we recognize three types of spatial distributions for intrusions in plume centre regions: 1) intrusions that circumscribe the plume centre emplaced along circular fault systems, 2) intrusions emplaced along rifts, in some cases rifts that converge towards the plume centre, and 3) single/unclassified intrusions. |
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