Learning Outcomes:
1. Critically evaluate, both orally in seminars and in written work, research articles on a variety of topics in igneous petrology and ore geology.
2. Plot, manipulate and carry out calculations on geochemical and isotope data and draw conclusions about the origin and evolution of magmas.
3. Make detailed petrographic descriptions of igneous rocks and from these descriptions draw conclusions on the origin, evolution and crystallization of these rocks.
4. Make detailed petrographic descriptions of mineralized rocks and from these descriptions draw conclusions on the mineralizing processes involved.
Indicative Module Content:
Igneous Petrology – 8 x 2-hour sessions including lectures, seminars and practical work.
1 and 2 Komatiites
Lecture and seminar focusing on petrogenesis including the question of magma water content, tectonic setting and conditions of crystallization; practical on description and interpretation of komatiites in thin section from Munro Township, Ontario. (Assoc. Prof. J.F. Menuge)
3 and 4 Lunar igneous petrology
Lecture and seminar focusing on the sources of information on lunar igneous petrology, the origin of the Moon, its early differentiation and mechanisms generating lunar basalts; practical based on description and textural interpretation of virtual microscope images of NASA lunar thin sections. (Assoc. Prof. J.F. Menuge)
5 and 6 Mid-ocean ridge basalts
Mantle melting at constructive plate margins. Mantle upwelling, melting columns sampling of heterogeneities. Influence of spreading rates, lithosphere thickness and regional temperature anomalies. Mechanisms of magma differentiation. Magmatic products and thermal/thickness evolution of oceanic crust. Insights from very slow spreading centres (SWIR and Gakkel). Constraints from melt inclusion studies. (Prof. P.F. McDermott)
7 and 8 Destructive plate margin magmatism
Subduction of oceanic crust and dehydration reactions. Fate of subducted slabs and sediments. Temperature profile through a subduction zone. Influence of volatiles on mantle solidus. Volatile transport into mantle wedge. Rates of wedge convection, replenishment and depletion. Magmatic products and their distinctive geochemistry. Data analysis using Excel to do basic calculations (Mg#) and data plotting. Interpretation of trace element ratio vs. isotope ratio correlations. (Prof. P.F. McDermott)
Ore Petrology – 10 x 2-hour sessions, including lectures, seminars and practical work, and a one-day field class to examine an active mineral exploration site in Ireland (venue to be confirmed). This excursion depends on collaboration with a mineral exploration company and if it has to be cancelled because of their operational reasons, there will be an additional 2 x 2-hour sessions on Bushveld PGE ores (see below) in its place.
1 and 2 The Navan Zn-Pb ore deposit, Co. Meath
Lecture and seminar focusing on the geological setting of the Navan deposit, the origin of fluid and dissolved materials, the role of faults, processes of ore precipitation and the timing of mineralization; practical introduces reflected light microscopy, followed by description and interpretation of Navan Zn-Pb ore in polished thin section. (Assoc. Prof. J.F. Menuge)
3 and 4 The Central African Copperbelt
Lecture and seminar focusing on the syles and timing of mineralization relative to deposition, diagenesis and faulting in the Central African Copperbelt, and origin of ore fluids and metals; practical on description and interpretation of Cu sulphide ore from Chibuluma, Zambian Copperbelt, in polished thin section. (Assoc. Prof. J.F. Menuge)
5 and 6 Porphyry ore deposits
Lecture and seminar focusing on the relationship of mineralization to host intrusions, chemical partitioning between magmas and hydrothermal fluids, the relationship between hydrothermal alteration and mineralization, and processes leading to ore deposition; practical on description and interpretation of Los Pelambres porphyry copper ore, Argentina in polished thin section. (Assoc. Prof. J.F. Menuge)
7 and 8 Iron oxide apatite (IOA) and iron oxide-copper-gold (IOCG) ore deposits
Lecture and seminar focusing on arguments for hydrothermal vs magmatic Fe oxide ores, models for origin of fluids and dissolved constituents in IOCG deposits, age relationships relative to host igneous rocks and the tectonic settings of IOCG mineralization; practical on description and interpretation of Fe oxide-P-REE ores of Pea Ridge, southeast Missouri in ordinary and polished thin section. (Assoc. Prof. J.F. Menuge)
9 and 10 Magmatic Ni-Cu-Co-PGE ores
Lecture and seminar focusing on magmatic processes leading to sulphide mineralization in the Sudbury and Noril’sk District intrusions, including sulphide liquid PGE enrichment and sulphide enrichment processes; practical on description and interpretation of Ni-Cu ores of Sudbury, Ontario in polished thin section. (Assoc. Prof. J.F. Menuge)
Mineral exploration field class
A one-day field class to an area of active mineral exploration in Ireland. Provisionally, this will be to localities in the south Leinster spodumene pegmatite belt, where several exploration companies are active. Spodumene pegmatites are the world's chief source of lithium, for which demand is rising because of its use in electric vehicle batteries. The field class will include a lecture on the geology of the south Leinster spodumene pegmatite belt, short visits to a few field localities, examination of exploration drill core and an introduction to how mineral exploration companies do their work. (Assoc. Prof. J.F. Menuge)
Bushveld PGE ores (if mineral exploration field class unavailable)
Lecture and seminar focusing on input to, and output from, the Bushveld magma chamber, and magmatic and hydrothermal processes leading to chromite, magnetite and platinum group element enrichments; practical on description and interpretation of Merensky Reef pegmatoid in ordinary and polished thin section. (Assoc. Prof. J.F. Menuge)