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IGCP 510 – A-TYPE GRANITES AND RELATED ROCKS THROUGH TIME | ![]() |
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| GLOBAL CORRELATION OF A-TYPE GRANITES AND RELATED ROCKS, THEIR MINERALIZATION, AND SIGNIFICANCE IN LITHOSPHERIC EVOLUTION | ||||
| Meetings & Field Trips | Results | Project Members | Contact Information | |
| Upcoming Events | Past Events |
October 1-3, 2009: Field trip ” A-type magmatic associations and related mineralizations at eastern-central Anatolia”, Anatolia, Turkey
This was the eleventh scientific field trip of IGCP-510, led by Drs. Ilkay Kuscu, Durmus Boztug, and Gonca Kuscu. The goals of the trip were to visit alkaline rock associations at Keban and Hasancelebi and related iron-oxide mineralizations. The focus was on the association of alkaline provinces with gold, copper and other mineralization. The mineral deposits in Anatolia helped to enable ancient civilizations to flourish; both ancient and modern mine sites were visited on the trip. The trip was attended by 16 participants from eight countries (Argentina, Australia, Brazil, Canada, India, Russia, Turkey, U.S.A.). The following program was carried out:
Day 1: Visits to alkaline rock associations at Keban and Hasancelebi, including syenites, trachytes and associated F-Mo mineralizations at Keban. Field observations and discussions on Hasancelebi magmatic rocks and associated iron-oxide mineralizations. Depart to Kangal and overnight stay at Balkili Cermik.
Day 2: Alkaline rock associations at Divrigi and associated iron-oxide deposits. Participants examined ophiolitic basement, and syenite porphyries with varying sodic and potassic alterations. Depart to Malatya.
The extension-related, A-type post-collisional intrusive rocks of Anatolia are genetically related to some of Turkey’s largest and economically most important ore deposits. The participants debated the relationship of these intrusions to I-type and S-type intrusions of similar age, and the tectonic setting that allowed this range of granite composition to be formed. A field trip guide was distributed to participants.
IGCP-510
symposium participants at Divrigi during the Turkey post-meeting excursion.
Active iron-oxide mines are located in the hills in the background.
Photos courtesy of Carol
Frost. (Click the Photo to Enlarge)
September 26-29, 2009: Meeting ”5th Annual Meeting of IGCP-510: A-type granites and related mineralization in the Tethyan Belt, from the Pyrenees through Turkey to Indonesia”, Tunceli University, Tunceli, Turkey
This was the fifth technical meeting of IGCP-510. The meeting was held at Tunceli University in eastern Turkey on September 29-30, 2009. The symposium was convened by Prof. Dr. Durmus Boztug, President of the Tunceli University and Prof. Dr. Carol Frost, University of Wyoming and project co-chair. The meeting gathered 26 researchers representing 9 countries (Argentina, Australia, Brazil, Canada, France, India, Russia, Turkey, U.S.A). 14 oral presentations on A-type granites and related rocks were given.
The symposium offered an excellent opportunity to discuss the association of A-type granites with other granite compositions (particularly I-type and S-type; all three of which occur together in localities in Turkey). Presentations encompassed a range of topics from classification, mineralization, tectonic associations, petrogenesis, and relationship to supercontinent formation and break-up. Data from A-type intrusions from many locations were discussed, including examples from Australia, Brazil, Turkey, India, Argentina, and China.
A program and abstracts of the meeting were distributed to participants. A proceedings volume based on the presentations given at the meeting will be published as a special issue of Turkish Journal of Earth Sciences, guest-edited by Durmus Boztug. The issue is projected to be completed in 2011.
Participants of
the 2009 Annual Meeting of IGCP-510 are welcomed by the students of Munzur
School, which hosted the second day of the technical sessions during the
symposium held in the provincial capital city, Tunceli.
Photos courtesy of Carol
Frost (Click the Photo to Enlarge)
September 26-29, 2009: Field trip: ” Geological field trip to the Cappadocian volcanic province”, Turkey
This was the tenth scientific field trip of IGCP-510. It was led by Dr. Vedat Toprak (Middle East Technical University, Turkey) and it focused on the ignimbrites and calc-alkalic volcanic centers of the Neogene-Quaternary Cappadocian volcanic province(CVP). The trip visited locations in order to understand three main periods in the evolution of the CVP: effusive centers of andesite composition ranging from 13.5 to 8.5 My; widespread ignimbrite deposition during the period 8.5 to 2.7 My; and large central volcanoes developed more recently than 2.7 My. The trip was attended by 12 participants from eight countries (Argentina, Brazil, Canada, France, India, Russia, Turkey, U.S.A.). The following program was carried out:
Day 0: Rendezvous and welcome dinner for the field trip participants in Ankara. Overnight in Ankara.
Day 1: Travel from Ankara to Cappadocia by way of the salt lake Tuz Golu, whose northeastern edge is fault-controlled. Visits to the ignimbrites of the Ihlara valley into which Byzantine-period rock-hewn cliff and underground settlements were excavated. The volcanic maar and geothermal fields of Slfular-Acigol were visited.
Day 2: The 9-14 Myr Kavak ignimbrite was the focus of this day’s excursion. This ignimbrite erodes to form distinctive ”fairy chimneys.” In the afternoon the tour continued to Elazig.
Day 3: The participants continued by bus to Tunceli.
The field trip offered the participants a thorough look at volcanic rocks that were erupted in a region of active faulting associated with the intersection of three major tectonic plates. The faults control the locus of volcanism, both central cones and volcanic edifaces, and multiple thick ignimbrites. The influence of the local geology on the development of early civilizations (geoarcheology) was a topic of lively discussion. A field trip guide was distributed to participants.
“Fairy Chimneys”
eroded from the 9-14My Kavak ignimbrite, near Goreme visited in during the
IGCP-510 pre-meeting field excursion in Turkey.
Photos courtesy of Carol
Frost. (Click the Photo to Enlarge)
August 14-22, 2009: Field conference “Eurogranites ARCTIC 2009” in Finnish Lapland and Kola Peninsula, Russia
This was the ninth scientific field trip of IGCP-510 and it was carried out as a joint venture with the Eurogranites network (Prof. B. Bonin, Université Paris-Sud, coordinator). The field trip was arranged by the Department of Geology, University of Helsinki (Prof. O. Tapani Rämö), the Geological Museum of the Finnish Museum of Natural History (Dr. Jaana Halla), and The Kola Science Centre of the Russian Academy of Sciences (Prof. Yuri Voytekhovsky). The trip posed a logistic challenge as it involved maneuvering a multi-national group of participants at arctic latitudes (~68oN) between Finland and far northwest Russia. There were two principal targets: (1) the Nattanen-type granites that have recently been identified as post-collisional, oxidized A-type granites; and (2) the classic Khibiny and alkaline complex of the Devonian Kola alkaline province in the heart of the Kola Peninsula. The site of the prime placer gold prospects in north-central Finnish Lapland, discovered 140 years ago, was also visited, and the Kola super deep borehole at the premises of the Russian Academy of Sciences in Apatity was examined. The trip was attended by 24 individuals from 14 countries (Belgium, Estonia, Finland, France, Germany, Ireland, Italy, Norway, Portugal, Russia, Slovakia, Switzerland, the United Kingdom, and the United States of America). The following program was carried out:
Day 0: Rendez-vous and introductory lecture of the field trip in Rovaniemi.
Day 1: River Sotajoki and the site of the Lapland gold rush in the late 1800’s.
Day 2: Nattanen-type Paleoproterozoic oxidized A-type granites. Two high-level multiple plutons, Riestovaara and Nattanen, were examined in detail.
Day 3: Transit to Russia, finishing the day in Murmansk.
Day 4: The Nattanen-type Litsa-Araguba granitoid complex (mingled diorite and granite and different granite varieties of the Portlubol pluton).
Day 5: A seminar with four key notes at the Kola Science Centre, Apatity. Examination of the Kola super deep borehole.
Day 6: A ~15-km traverse through the alkaline (undersaturated) plutonic rock types (ijolite, urtite, melteigite etc.) of the classic Khibiny (Hiipinä) complex.
Day 7: Tinguaite dikes in the west-central part of the Hiipinä complex.
Day 8: Return to Finland and wrap-up meeting in Rovaniemi.
Eurogranites Arctic 2009 provided the participants with a state-of-the-art account of the geology of northern Finland and adjacent Russia as well as the petrogenesis of the Nattanen-type A-type granites (on both sides of the border) and the alkaline massifs of Khibiny and Lovozero, the two prominent plutons of the Kola alkaline province. The conference also shed light on the history and development of placer gold in Finnish Lapland and the structure, lithology, and petrography of the rock types recovered from the 11.5-km Kola borehole.
A field trip guide
E. Heilimo, V.R. Vetrin, J. Halla, M.I. Kurhila, O.T. Rämö, A.P. Heinonen (2009) Eurogranites 2009 – ARCTIC. Field conference guide, August 15th to 22nd, 2009. Department of Geology, University of Helsinki, Geological Museum, University of Helsinki, Geological Institute, Kola Science Centre, Russian Academy of Sciences, 87 p.
was published.
On August 14-22,
2009, IGCP-510 and the Eurogranites network (B. Bonin, coordinator) co-arranged
a nine-day field conference in northern Finland and adjacent Russia (Kola
Peninsula) with Paleoproterozoic oxidized A-type granites and the Khibiny
alkaline massif as the principal targets. The participants also had a chance to
examine the core of the Kola Superdeep borehole.
Photos courtesy of Esa
Heilimo and O.T. Rämö. (Click the Photo to Enlarge)
September 1-7, 2008: Field trip ”The Permian-Triassic A-type volcanic-plutonic igneous suite of Corsica”,
This was the eight scientific field trip of IGCP-510. The trip was arranged by Bernard Bonin (Université de Paris-Sud) and it focused on the volcanic and plutonic A-type suites of
Day 0: Assembly at
Day 1: The Tana-Peloso complex: a mafic layered igneous complex, monzonite and syenite intrusions, subsolvus granite dyke.
Day 2: The Cauro-Bastelica ring complex: camptonite dykes, hypersolvus granites, transsolvus granite, subsolvus granite, rhyolite breccias and domes.
Day 3: The Ota-Porto ring complex: gabbro, biotite subsolvus granite, biotite transsolvus granite, hybric rocks.
Day 4: The Evisa ring complex: classic locality of peralkaline alkali feldspar granite (cupola-forming), an early subsolvus syenogranite, and late bimodal dykes.
Day 5: The Scandola and Seninu calderas: intra-caldera ignimbrites (K-rich rhyolite) and sedimentary rocks, complex set of concentric caldera ring faults and other cauldron subsidence structures. Mafic lavas (basalt, hawaiite).
Day 6: Departure from
The Permo-Triassic A-type suites of
A field trip guide
B. Bonin, B. Platevoet, F. Poitrasson, M.R. Renna (2008) Eurogranites-IGCP510 2008 Joint field-meeting – Alkaline The Permian-Triassic A-type volcanic-plutonic igneous suite of Corsica. Université de Paris-Sud, Paris, 54 p.
was published.
IGCP-510 September 1-7, 2008 field trip participants examining the Permo-Triassic A-type granite suites of Corsica (in particular, the Porto and Evisa ring complexes) with Bernard Bonin as the guide (at center, at Tolla dam).
Photos courtesy of Matti Kurhila. (Click the Photo to Enlarge)
August 7-8, 2008: Meeting ” Granite Classification – a Never-ending Problem”, 33rd IGC,
This was the fourth Annual (fifth technical) Meeting of IGCP-510. It was arranged in conjunction with the 33rd International Geological Congress that was held in the
The International Geological Congress is arranged every four years and now provided the project with an audience wider than usual. The joint symposium with the IUGC Subcommission of Systematics of Igneous Rocks was tailored to this end to draw colleagues also from more distant sectors of the field. Specific topics related to classification of granites included A-saturation, overall alkalinity, the TAS space, and redox budget as typological criteria. The salient traits in distinguishing alkaline and calc-alkaline granitic suites were outlined as well. Furthermore, the given presentations also covered Archean A-type granites, Proterozoic A- and I-type volcanism in northern South America (Guyana shield), as well as A-type granites of Siberia and Iran.
An IGCP-510 Business Meeting was held on August 8, 2008 at the Norway Convention Centre in Lillestrøm to review the achievements and plan the future activities of the project. The meeting was chaired by O.T. Rämö and R. Dall’Agnol and it was attended by 14 individuals representing
The abstracts of the IGCP-510 symposium were published in the 33IGC Abstract Volume [CD-ROM].
The King of Norway, HM King Harald V addressing the Opening Ceremony of the 33rd IGC on August 6, 2009.
Photos courtesy of O.T. Rämö. (Click the Photo to Enlarge)
August 1-5, 2008: Field trip: ”Alkaline rocks of the
This was the seventh scientific field trip of IGCP-510. The trip was arranged by Tom Andersen (
Day 0: Rendez-vous and introductory lecture for the field trip at the Department of Geosciences,
Day 1: General geology of the
Day 2: Various intrusive phases (rapakivi, biotite granite, aplite) of the subvolcanic
Day 3: The ~280 Ma Siljan-Mykle plutonic complex with larvikite, gabbro/diorite, nepheline syenite, nordmarkite (saturated miarolitic syenite), and miarolitic alkali granite.
Day 4: The Larvik pluton (a composite ring intrusion) was examined at the ”Blue Pearl” quarry in the southern part of the rift. This exposed a spectacular nepheline syenite pegmatite with microcline, nepheline, sodalite, ferrokentbrookite, wöhlerite, and leucophane as the main constituents. Layered larvikite in shore cliffs at Ula were also examined. Return to
The field trip offered the participants a good look at an undoubtedly rift-related, Phanerozoic A-type granite suite that also includes a wealth of undersaturated silicate rocks. This promoted a lively petrologic discussion on saturated vs. undersaturated magmatic lineages. The examined plutons are all high-level structures and their relationships to the volcanic rocks of the rift and supracrustal rocks preceding the onset of rifting (as well as the local Precambrian basement) could be easily observed. Skarn-type Pb-Zn-Cu deposits and late-magmatic Mo-W mineralization associated with these A-type rocks were also examined.
A field trip guide
T. Andersen, R.G. Trønnes, O. Nielsen, A.O. Larsen (2008) Eurogranites 2008/IGCP 510 field trip 2008 – Alkaline rocks of the Oslo Rift,
was published.
IGCP-510 August 1-5, 2008 field trip participants examining the saturated and undesaturated plutonic and volcanic alkaline igneous suites in the Phanerozoic Oslo Graben and the surrounding Precambian bedrock. The quarry photo shows a spectacular nepheline syenite pegmatite at the “Blue Pearl” site.
Photos courtesy of O.T. Rämö. (Click the Photo to Enlarge)
May 26-28, 2008: Meeting ” Anorthosites to Rapakivi Granites: a Tribute to the Career of Ronald F. Emslie” in
This was the fourth technical meeting of IGCP-510. The meeting (symposium SS16) was arranged in conjunction with the the GAC-MAC-SEG-SGA Joint Annual Meeting in
The symposium offered an excellent opportunity to discuss the bimodal aspects of A-type granite suites, the relation of these granites to the mid-Proterozoic massif-type anortosites in particular. A quite varied set of topics on the subject was covered, both thematically (isotope geochemistry, geochronology, magnetic susceptibility, petrologic evolution, tectonic setting, typology, origin of associated Fe-Ti-P ore deposits) and in terms of the geographic distribution of A-type granite–massif-type anothosite suites (new data were presented for magmatic suites in the Grenville province, Labrador, Wyoming, Brazil, central Africa, the Fennoscandian and Ukrainian shields, Poland).
The program and abstracts of the symposium were published in the GAC-MAC-SEG-SGA Joint Annual Meeting Program Volume (#33, ISBN 978-1-897095-36-2) and Abstract Volume (#33, ISBN 978-1-897095-35-5), respectively. A proceedings volume based on the presentations given at the SS16 symposium will be published as a special issue of the Canadian Mineralogist, guest-edited by M.A. Hamilton, J.S. Scoates, and O.T. Rämö. The issue will be completed in 2009/2010.
IGCP-510 May 26-28, 2008 symposium was arranged in
Photos courtesy of Aku Heinonen and O.T. Rämö. (Click the Photo to Enlarge)
November 1-4, 2007: Field trip ”Coeval Miocene Magmatism and Crustal Extension in the Colorado River and Death Valley Extensional Terrains” in southern
This was the sixth scientific field trip of IGCP-510. The trip was arranged by J.P. Calzia (U.S. Geological Survey), S. Luddington (U.S. Geological Survey), C.F. Miller (Vanderbilt University, Nashville), and O.T. Rämö (co-leader of IGCP-510, University of Helsinki, Finland). The trip focused on the results of recent geologic, petrologic, and isotopic studies of Miocene A-type plutonic and volcanic rocks in the Colorado River and Death Valley extensional terrains in the southern Basin and
Day 1: Ground transport from
Day 2: Different varieties of the
Day 3:
Day 4: The 9.8 Ma high-level A-type rapakivi porphyry of the Shoshone pluton (the world’s youngest exposed rapakivi granite), 8.5-7.5 Ma Shoshone volcanics (flows and tuffs), and 7-5 Ma Greenwater volcanics. Return to
The trip offered an excellent opportunity to examine a thoroughly studied, young A-type granite terrain within an undoubtedly extensional tectonic regime (Basin and
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IGCP-510 November 1-4, 2007 field trip participants examining the Miocene (18-5 Ma Ga) A-type granites and associated volcanic rocks in the grossly extended terrains of the Colorado River extensional Corridor (southernmost Nevada) and Death Valley (southeastern California). The close-up photo shows Proterozoic (~1.38 Ga) carbonatite from the Photos courtesy of O.T. Rämö. (Click the Photo to Enlarge) | ||
July 7-10, 2007: Field trip ”Bushveld Granites and Associated Mineralization” in the Bushveld Igneous Province, South Africa
This was the fifth scientific field trip of IGCP-510. The trip was arranged by J. Kinnaird (University of the Witwatersrand) and L. Robb (IGCP-510 co-leader;
Day 1: Ground transport from
Day 2: Six targets in the field featuring different facies of the Nebo and Klipkloof granites (the latter tourmaline bearing and albitized).
Day 3: Tin-tungsten-rare earth element mineralization associated with the Lease and Bobbejaankop alkali feldspar granites. Marlin dimension stone quarry (Africa Red) in the Bobbejaankop granite.
Day 4: Iron-enriched fluorite-bearing Vergenoeg volcanic breccia pipe, agglomerates and ignimbrites as well as associated fluorite mine and fayalite granite. Return to
The participants had an excellent opportunity to examine several of the Paleoproterozoic A-type granites associated with the classic Bushveld mafic layered igneous complex. These granites are also associated with a great variety of mineralization types: polymetallic Cu-Pb-Zn-Ag-U-F concentrations in quartz-hematite veins in granite apical facies; late magmatic tabular, disseminated, and pipe-form Sn-W-REE mineralizations; and a world-class fluorite deposit (Vergenoeg) related to Paleoproterozoic explosive volcanic activity. A field trip guide [J. Kinnaird, L. Robb (2007) Excursion guide to the Bushveld Granites and associated mineralization; post Hutton conference field trip 2007. Economic Geology Research Institute, School of Geosciences, University of the Witwatersrand, Johannesburg, South Africa, 46 p.] was published.
July 2-6, 2007: Sixth International Hutton Symposium; Origin of Granites and Related Rocks at the Stellenbosch University, Stellenbosch, South Africa (http://academic.sun.ac.za/geology/hutton/hutton2007.htm)
This was the third annual meeting of IGCP-510 and it was arranged in conjunction with the Sixth International Hutton Symposium on the origin of granites and related rocks. The symposium gathered together ~90 researchers, 20 of them with A-type granites and related rocks as principal expertise, representing 13 countries (
The Hutton Symposium is arranged every four years and belongs together granite experts from all over the word. Thus the symposium was beneficial to the IGCP-510 membership, not only as a venue of granite researchers with A-type granites as a common denominator, but also by offering an excellent opportunity to discuss pertinent matters with the rest of the granite community. The presentations given covered all the topics relevant to IGCP-510 (origin, evolution, typology, tectonics, and metallogenesis of A-type granites and related rocks), with new insights, e.g., into the petrogenesis of A-type granites (mantle degassing and resultant metasomatism of lower crust in extensional continental systems, experimental and melt inclusion modeling of high-F A-type systems) and their classification (a new scheme based on geochemistry to investigate the relationship between the alkaline and A-type rocks associations).
An IGCP-510 Business Meeting was held on July 3, 2007 at the Department of Geology,
An abstract volume [J.A. Miller, A.F.M. Kisters (Comps. and Eds.) (2007) 6th International Hutton Symposium, Abstract Volume & Program Guide. Department of Geology, Geography and Environmental Sciences, IGCP-510 July 2-6, 2007 Hutton Symposium in Stellenbosch, South Africa. Photo courtesy of O.T. Rämö. (Click the Photo to Enlarge)
August 10-15, 2006: Field trip ”Archean and Paleoproterozoic Granitoids of the
This was the fourth scientific field trip of IGCP-510. It was arranged by R. Dall'Agnol (Federal University of Pará), M.A. de Oliveira (Federal University of Pará), J. de Arimatéia Costa de Almeida (Federal University of Pará), F.J. Althoff (Vale do Rio dos Sinos University – UNISINOS – Rio Grande do Sul state of Brazil), A.A. da Silva Leite (Companhia Vale do Rio Doce), D.C. de Oliveira (Federal University of Pará), and C.E. de Mesquita Barros (Federal University of Pará). The trip focused on Paleoproterozoic A-type granites (reduced and oxidized) and Archean TTGs, sanukitoids, leucogranites, and A-type granites, as well as associated iron, manganese, copper, gold, and nickel mineralization The trip was attended by 23 individuals from six countries (Australia, Brazil, Colombia, Finland, Canada, United States). The following itinerary was realized:
Day 1: Ground transport from Marabá to Redenção. Technical introduction to the field trip.
Day 2: Eight targets in the field. These comprised late Archean (2.96-2.87 Ga) granitoids (TTGs, sanukitoids), as well as different facies of the 1.88 Ga Redenção A-type granite pluton.
Day 3: Five field targets in the field. These included the Archean sanukitoid Rio Maria granodiorite and associated layered mafic rocks. Paleoproterozoic dike rocks, one of these a composite dike associated with the 1.88 Ga oxidizing A-type granites, were also examined.
Day 4: Six field targets, featuring Archean pillow lavas and various TTG granitoids and sanukitoids.
Day 5: Four field trip stops, with Archean calc-alkaline leucogranites, the Planalto subalkaline A-type granite, and the Sossego Cu-Au mine as the prime targets.
Day 6: Three stops in the field. These comprised the Carajás BIF suite, the Estrela granite (2.73 Ga), and the Paleoproterozoic (~1.88 Ga) Serra dos Carajás granite. Ground transport from Redenção to Marabá.
The participants had a chance to examine the truly anorogenic, oxidized A-type granites (the classic Jamon suite) that were emplaced into the late Archean Rio Maria granite-greenstone terrain at ~1.88
August 6-9, 2006: Symposium “A-type Granites and Related Rocks through Time” at Hotel Sagres, Belém,
This was the second annual meeting of IGCP-510 and it gathered together ~50 researchers from six countries (
The meeting gathered together a substantial number of earth scientists with A-type granites as a common denominator, those from Latin America (
(1) Reviews were given on the state of the art geochemistry of A-type granites and AMCG (anorthosite-mangerite-charnockite-granite) suites;
(2) A new model for A-type granites and rhyolites was proposed, with mantle degassing and resultant metasomatism of lower crust in divergent continental systems as the key factor;
(3) Several new A-type granite occurrences were described (e.g., in Antarctica and
(4) Oxygen fugacity as a controlling variable in A-type granite petrogenesis was elaborated; and
(5) Metallogenic traits of A-type granites were scrutinized via a partisan review and case studies.
The presentations given provided important novel ideas regarding the origin, evolution, and metallogenesis of A-type granite suites, and they yield a basis to plan further activities of the project. An IGCP-510 Business Meeting was held on August 7 at Hotel Sagres to plan the future activities of the project. The meeting was chaired by O.T. Rämö and R. Dall’Agnol and it was attended by 25 individuals from
An abstract volume R. Dall’Agnol, L.T. Rosa-Costa, E.L. Klein (Eds.) (2006) Symposium on Magmatism, Crustal Evolution, and Metallogenesis of the Amazonian Craton. Abstracts Volume and Field Trips Guide. Belém, PRONEX-UFPA/SBG-NO, p. 1-80 was released.
A proceedings volume based on the presentations given at the A-type granite workshop will be published as a special issue of The Canadian Mineralogist. The issue will be edited by R. Dall’Agnol, O.T. Rämö, and R. Martin and will be published in 2008.
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July 2-6, 2007 Symposium on Magmatism, Crustal Evolution, and Metallogenesis of the Amazonian Craton in Belém, Photos courtesy of R. Dall'Agnol. (Click the Photo to Enlarge) | |||
August 2-5, 2006: Field trip to the Pitinga Mine and surrounding bedrock in Pitinga, Amazonia, Brazil (60°00'W, 0°50'S)
This was the third scientific field trip of IGCP-510. The trip was arranged by H.T. Costi (Museu Paraensi Emílio Goeldi), J.M.T.M. Ferron (Paranema Group, Mineração Taboca S/A), and M. Prado (Paranema Group, Mineração Taboca S/A) and it focused on the Paleoproterozoic (~1.82 Ga) Zr-Nb-Sn-mineralized A-type granites and their Paleoproterozoic country rocks in the Pitinga province on the southern flank of the Guiana shield in northern Brazil. The principal targets were the
Day 1: Ground transport from
Day 2: Eight targets in the field featuring the albite granite, biotite granite, rapakivi, and hypabyssal facies of the
Day 3: Five field targets associated with the Água Boa pluton (topaz granite, amphibole-biotite granite, biotite granite, tin greisen) and the Paleproterozoic volcanic country rocks of the pluton.
Day 4: Ground transport from Pitinga to
This was a rare occasion (realized via excellent collaboration with and generous support from the Paranema Group, Mineração Taboca S/A) to examine the world-class tin-deposit, large xenotime reserves, and cryolite mineralization associated with the A-type
September 11-17, 2005: The Eurogranites 2005 field conference to southern and central Finland (http://www.fmnh.helsinki.fi/eurogranites)
IGCP-510 also co-sponsored the Eurogranites 2005 field conference to southern and central Finland. The conference brought together 47 individuals from 15 countries (Belgium, Estonia, Finland, France, Germany, Ireland, Italy, Japan, Norway, Poland, Romania, Slovakia, Spain, United Kingdom, United States) to examine the origin and significance of Proterozoic and Archean granitoid rocks along a traverse from the southern to east-central Finland. Specific targets included (i) the classic A-type ~1.64 Ga rapakivi granites and related mafic rocks of southeastern Finland; (ii) the orogenic granitoids of the ~1.9 Ga Svecofennian orogen; and (iii) the sanukitoids, TTG suites, and A-type granites of the late Archean Karelian craton.
A field trip guide (O.T. Rämö, J. Halla, M. Nironen, L.S. Lauri, M. Kurhila, A. Käpyaho, P. Sorjonen-Ward, O. Äikäs, 2005, EUROGRANITES 2005 - Proterozoic and Archean Granites and Related Rocks of the Finnish Precambrian. Eurogranites 2005 Field Conference, September 11-17, 2005. Publications of the Department of Geology A1, 130 pp. (Download PDF) was published.
May 26-30, 2005: Post-conference field trip AC-4 "Extrusive A-type magmatism of the Yellowstone hot spot track" (http://www.the-conference.com/2005/gold2005/field_trips/AfterConference-4.pdf)
The first scientific field trip of IGCP-510 was arranged by C.D. Frost (University of Wyoming), M. McCurry (Idaho State University), R. Christiansen (U.S. Geological Survey, Menlo Park), K. Putirka (California State University, Fresno), and M. Kuntz (U.S. Geological Survey, Denver) and it focused on extrusive A-type magmatism (both silicic and mafic) of the Yellowstone hot spot track that features volcanic complexes ranging in age from mid-Miocene (south-central Idaho) to Holocene (Yellowstone). The trip was attended by 27 individuals from nine countries (Argentina, Australia, Brazil, Finland, France, Japan, People’s Republic of China, Russia, United States). The following targets were examined:
Day 1: Salmon River suture zone; olivine tholeiite in eastern Snake River Plain.
Day 2: Tertiary rhyolite ignimbrites in eastern Snake River Plain; tholeiitic to ferrolatite lavas of the Magic Reservoir eruptive center; mafic to intermediate extrusives of the Craters of the Moon.
Day 3: A-type rhyolitic differentiates of ferrobasalt at Cedat Butte; 1.2 Ma caldera-forming reuption of the Yellowstone volcanic system at Island Park.
Day 4: Yellowstone caldera and environs in Yellowstone National Park.
Day 5: Berkeley Pit, Butte, Montana.
The field trip was attended by project delegates from around the world and clearly established the significance of hot-spot associated continental magmatic terrains in the petrogenesis of the volcanic counterparts of A-type granites. These include hot, high-silica rhyolites and related pyroclastic rocks and Fe-enriched tholeiitic mafic lavas that must be cogenetic with the silicic end of the observed lithologic spectrum. These observations will help to further expand our knowledge about the petrologic evolution of A-type granite suites and associated mineralization. A field trip guide (C. Frost, M. McCurry, B. Christiansen, K. Putirka, M. Kuntz, 2005, Extrusive A-type magmatism of the Yellowstone hot spot track, 15th Goldschmidt Conference Field Trip AC-4. Field Trip Guide, University of Wyoming, 76 pp. plus an appended map) was released.
At a wrap-up meeting of the field trip, the following issues relevant to IGCP-510 were discussed:
(1) Regarding volcanic A-type suites, high-silica members may only be present as extrusive rocks.
(2) A-type granites may be formed by several different petrogenetic processes and this will pose a particular challenge to the project.
(3) The highly evolved (ferrodioritic) endmember of A-type suites may be formed by fractionation of tholeiitic mantle-derived magmas and pertinent suites should be comprehensively examined.
(4) The range of mineralization types
associated with A-type granites and their economic potential should be examined in detail.
In order to assess these, and other relevant, issues in relation to A-type granite suites, the project will initiate a global-scale data base of A-type granites.
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IGCP-510 field trip participants hike through Craters of the Moon National Monument, Eastern Snake River Plain, Idaho (May 27, 2005), and examine the Yellowstone Caldera (Wyoming) with Bob Christiansen (May 28-29, 2005). Photos courtesy of C. Frost. (Click the Photo to Enlarge) | ||
May 20-25, 2005: Inaugural Meeting of IGCP-510 at the 15th Goldschmidt Conference (Moscow, Idaho, USA) (http://www.the-conference.com/2005/gold2005/)
The inaugural meeting of IGCP-510 gathered together 32 researchers from eleven countries in Latin America, North America, Asia, and Europe (i.e., Argentina, Brazil, Canada, Finland, Japan, People’s Republic of China, Portugal, Republic of Korea, Russia, United Kingdom, United States). The meeting was convened by C.D. Frost, R. Dall’Agnol, and O.T. Rämö and it was organized as a special session (S08; in total, 22 oral and poster presentations) of the 15th Goldschmidt Conference under the general theme of the project ”A-type Granites and Related Rocks through Time”.
The meeting managed to get together a versatile group of earth scientists with A-type granites as a common denominator to discuss the state of the art of A-type granite suites and to plan further activities of IGCP-510. The presentations given covered a wide range of topics relevant to the project:
(1) the 25-year history of the A-type granite concept (by J.B. Whalen and B. Bonin, two pioneers in the field);
(2) A-type plutonic activity in Archean (Siberia), Proterozoic (southern and midcontinental United States, Brazil, Siberia, Finland), and Mesozoic (southern
Andes, Turkey, Namibia, China) continental realms;
(3) A-type volcanic associations (western United States, Andes, East Africa);
(4) Metallogeny of A-type granites (sodalite and cryolite-tin deposits); and
(5) Isotopic (Hf, Nd, Sr, Pb, O) calibration of A-type granite suites.
The presentations provide a good basis to plan further activities of the project and to refine the goals of IGCP-510. For example, the 2006 annual meeting of the project will focus on Archean-Proterozoic evolution of A-type granite suites that presumably register several different liquid lines of descent, and on Zr-Nb-Sn mineralization associated with these suites in the northern and eastern part of the Amazonian craton (Brazil).
The abstracts of the papers given at the IGCP-510 session of the Goldschmidt Conference were published in a special issue of Geochimica et Cosmochimica Acta (vol. 69, 10S, pp. A79-A89). The session convenors will co-edit a special issue of Lithos (Elsevier B.V.) entitled ”A-type Granites and Related Rocks through Time”. This will comprise 15-20 full papers and will be published by the turn of 2006/2007. The volume will provide a comprehensive piercing point upon which the future achievements of the project will be reflected. Inaugural Meeting of IGCP-510 was held at the 15th Goldschmidt Conference in
Photos courtesy of O.T. Rämö. (Click the Photo to Enlarge)