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The 13th Symposium on Polar Science/Ordinary sessions [OG] Polar geosciences, Wed. 16 Nov.

We carried out SHRIMP zircon U-Pb dating on A-type granitic intrusions from the Namaqua-Natal Province, South Africa, Sverdrupfjella, western Dronning Maud Land, Antarctica and the Nampula Province of northern Mozambique. Zircon grains in these granitic rocks are typically elongated and oscillatory zoned, suggesting magmatic origins. Zircons from the granitoid intrusions analyzed in this study suggest ∼1025–1100 Ma ages, which confirm widespread Mesoproterozoic A-type granitic magmatism in the Namaqua-Natal (South Africa), Maud (Antarctica) and Mozambique metamorphic terrains. No older inherited (e.g., ∼2500 Ma Achean basement or ∼1200 Ma island arc magmatism in northern Natal) zircon grains were seen. Four plutons from the Natal Belt (Mvoti Pluton, Glendale Pluton, Kwalembe Pluton, Ntimbankulu Pluton) display 1050–1040 Ma ages, whereas the Nthlimbitwa Pluton in northern Natal indicates older 1090–1080 Ma ages. A sample from Sverdrupfjella, Antarctica has ∼1091 Ma old zircons along with ∼530 Ma metamorphic rims. Similarly, four samples analysed from the Nampula Province of Mozambique suggest crystallization ages of ∼1060–1090 Ma but also show significant discordance with two samples showing younger ∼550 Ma overgrowths. None of the Natal samples show any younger overgrowths. A single sample from southwestern Namaqualand yielded an age of ∼1033 Ma.Currently available chronological data suggest magmatism took place in the Namaqua-Natal-Maud-Mozambique (NNMM) belt between ∼1025 Ma and ∼1100 Ma with two broad phases between ∼1060–1020 Ma and 1100–1070 Ma respectively, with peaks at between ∼1030–1040 Ma and ∼1070–1090 Ma. The age data from the granitic intrusions from Namaqualand, combined with those from Natal, Antarctica and Mozambique suggest a crude spatial-age relationship with the older >1070 Ma ages being largely restricted close to the eastern and western margins of the Kalahari Craton in northern Natal, Mozambique, Namaqualand and WDML Antarctica whereas the younger

The 11th Symposium on Polar Science/Ordinary sessions: [OG] Polar Geosciences, Poster presentations, Mon. 16 Nov. - Fri. 18 Dec.

The Tenth Symposium on Polar Science/Ordinary sessions: [OG] Polar Geosciences, Wed. 4 Dec. / Entrance Hall (1st floor), National Institute of Polar Research

The Ninth Symposium on Polar Science/Ordinary sessions: [OG] Polar Geosciences, Wed. 5 Dec. / 3F Seminar room, National Institute of Polar Research

The Ninth Symposium on Polar Science/Ordinary sessions: [OG] Polar Geosciences, Wed. 5 Dec. / Entrance Hall (1st floor), National Institute of Polar Research

We summarize U–Pb age data for the Lutzow–Holm Complex (LHC) in East Antarctica and propose the following geological subdivisions based on protolith ages, along the coast of Dronning Maud Land from southwest to northeast: the Innhovde Suite (INH, 1070–1040 Ma) composed mainly of felsic orthogneiss; the Rundvagshetta Suite (RVG, 2520–2470 Ma), mostly felsic orthogneiss with minor mafic and metasedimentary gneisses; the Skallevikshalsen Suite (SKV, 1830–1790 Ma), felsic to mafic orthogneiss with abundant dolomitic marbles, calc-silicates and other metasediments; the Langhovde Suite (LHV, 1100–1050 Ma), mostly felsic orthogneiss with minor mafic and calc-silicate gneisses; the East Ongul Suite (EOG, 630 Ma), with various orthogneisses and metasediments; and the Akarui Suite (AKR, 970–800 Ma) with diverse orthogneisses and paragneisses. The oldest crustal components of the LHC lie in the southern part of Lutzow–Holm Bay, and consist of late Neoarchean and Paleoproterozoic protoliths to charnockites and enderbites that dominate the Rundvagshetta and Skallevikshalsen Suites. This older domain is surrounded by gneisses and granulites with late Mesoproterozoic to early Neoproterozoic protolith ages, including the Innhovde Suite and the Langhovde Suite. The Akarui Suite contains diverse orthogneisses with Neoproterozoic protoloiths, and the youngest unit is the East Ongul Suite with protolith ages of ~630 Ma. Cape Hinode, located geographically within the Akarui Suite, underwent high-grade metamorphism at ~960 Ma that is much older than that which produced the gneisses and granulites of the surrounding LHC (~600–520 Ma). Cape Hinode is therefore exotic, independent of the surrounding LHC, and defined as the “Hinode Block”. The boundaries proposed in this paper are largely consistent with those inferred from magnetic anomalies, gravity anomalies, and bedrock topographical data.

Kennicutt, M.C. et. al.-- 17 pages, 3 figures, The Antarctic Roadmap Challenges (ARC) project identified critical requirements to deliver high priority Antarctic research in the 21st century. The ARC project addressed the challenges of enabling technologies, facilitating access, providing logistics and infrastructure, and capitalizing on international co-operation. Technological requirements include: i) innovative automated in situ observing systems, sensors and interoperable platforms (including power demands), ii) realistic and holistic numerical models, iii) enhanced remote sensing and sensors, iv) expanded sample collection and retrieval technologies, and v) greater cyber-infrastructure to process ‘big data’ collection, transmission and analyses while promoting data accessibility. These technologies must be widely available, performance and reliability must be improved and technologies used elsewhere must be applied to the Antarctic. Considerable Antarctic research is field-based, making access to vital geographical targets essential. Future research will require continent- and ocean-wide environmentally responsible access to coastal and interior Antarctica and the Southern Ocean. Year-round access is indispensable. The cost of future Antarctic science is great but there are opportunities for all to participate commensurate with national resources, expertise and interests. The scope of future Antarctic research will necessitate enhanced and inventive interdisciplinary and international collaborations. The full promise of Antarctic science will only be realized if nations act together, The authors recognize the financial support that made the Scan and ARC possible. The Council of Managers of National Antarctic Programs (COMNAP), the Tinker Foundation and the Scientific Committee on Antarctic Research (SCAR) provided the majority of the funding for this project including the costs of travel and participation of invited, non-COMNAP workshop attendees. In-kind support was provided by many COMNAP-Member national Antarctic programmes including Dirección Nacional del Antártico (DNA, Argentina), Australian Antarctic Division (AAD, Australia), Programa Antártico Brasileiro (PROANTAR, Brazil), Instituto Antártico Chileno (INACH, Chile), Polar Research Institute of China (PRIC, China), Instituto Antártico Ecuatoriano (INAE, Ecuador), Institut Polaire Français Paul Emile Victor (IPEV, France), Alfred Wegener Institute (AWI, Germany), National Institute of Polar Research (NIPR, Japan), Korea Polar Research Institute (KOPRI, Republic of Korea), Antarctica New Zealand (New Zealand), Arctic and Antarctic Research Institute (AARI, Russia), Spanish Polar Committee (CPE, Spain), British Antarctic Survey (BAS, UK), and the US National Science Foundation (NSF, USA)

SUMMARYThe prohibition of commercial mineral resource extraction through the Antarctic Treaty System has removed one significant source of potential damage to Antarctica's geological and geomorphological values. However, given the on-going increase in Antarctic tourism and scientific footprint, some high-quality geological features may be vulnerable to human impact, such as damage due to the construction of logistical facilities, unregulated collection of geological specimens or oversampling for scientific purposes. The Protocol on Environmental Protection to the Antarctic Treaty puts in place a framework for the protection of Antarctica's environmental, scientific, historic, wilderness and aesthetic values. However, the Antarctic Protected Area system is still immature and further implementation of existing management tools may be required to protect the diverse range of vulnerabilities, qualities and spatial scales represented in the geology and geomorphology of the continent. At sites where high-quality mineralogical or palaeontological specimens exist in limited quantities, considerations of how best to prevent oversampling and manage access to remaining material may be supported by assessment of cumulative impacts. Examination of the level of Antarctic specimen loans from a selection of national geological collections suggested that existing publically accessible geological collections could be better utilized, which could reduce environmental impact and oversampling at vulnerable Antarctic sites.

We applied SHRIMP zircon U-Pb age dating to ultrahigh-temperature (UHT) sapphirine-bearing orthopyroxene garnet (SOG) granulite and biotite-hornblende (Bt-Hbl) gneiss in the Schirmacher Hills, East Antarctica. In the Bt-Hbl gneiss, concordant ages of and Ma were obtained from zircon overgrowth rims and zircon cores, with oscillatory and irregular zoning, respectively. The zircon overgrowth rims ( Ma) with low Th/U ratios from the Bt-Hbl gneiss are interpreted as having a metamorphic origin. Oscillatory-zoned and/or irregularly zoned zircon cores may have crystallized during an igneous event at Ma; 800-Ma igneous events have not previously been recognized in central Dronning Maud Land (DML) inland nunatak. Zircons in the SOG granulite yielded a concordant age of Ma, using analyses of sector-zoned and simple-zoned grains. These zircons have relatively high Th/U ratios with a narrow range, and they occur in association with garnet breaking down to form cordierite. The -Ma age obtained from these zir...

Conventional alkali-catalyzed BDF production processes have a serious problem because the settling of liquid dispersions after transesterification is slow and requires almost one day. The present study suggests a significant improvement using a simple method called PITE, i.e., strong agitation during transesterification in a fully baffled stirring vessel. The PITE method can invert the dispersions from an alcohol-in-oil (A/O) to an O/A type which settles within 20 seconds. The transesterification reaction immediately reaches its equilibrium after phase inversion, in which the reaction time is less than 2 min. It is estimated from this result that conventional batch-wise BDF production using a 100 L vessel can be replaced by an equivalent continuous operation with a 0.15 L vessel.

日豪両国間における南極研究の情報交換ならびに将来への協力関係の更なる発展と強化に資する目的で日豪南極研究協力体制に関するワークショップが2008年6月12日、オーストラリア南極局から4名、国立極地研究所から10数名の研究者の参加のもと開催された。研究協力、プロジェクトの検討及びその合意に向けて、さらにそれを両国の研究計画に反映させるためには、さらなる実務レベルでの話し合いが必要であるとの認識で一致した。本ワークショップは2009年前半までに日豪南極研究合同セミナーを開催する必要がある旨合意した。, A workshop on future Australian-Japanese Antarctic cooperation was held on 12 June 2008 to exchange scientific information and to initiate a dialog to explore the way forward to further enhance and strengthen collaboration in Antarctic science between the two nations. The workshop was attended by four Australian Antarctic Division (AAD) scientists and more than ten National Institute of Polar Research (NIPR) scientists. Through a series of presentations detailing both countries' projects, and the following discussion, the workshop agreed that there are compelling reasons for holding a joint seminar between Australia and Japan by early next year to prioritize and agree to areas of collaboration, and outline the sorts of projects to be reflected in research plans of both countries.

Analysis of new lithological, structural, metamorphic and geochronological data from extensive mapping in Mozambique permits recognition of two distinct crustal blocks separated by the Lurio Belt shear zone. Extrapolation of the Mozambique data to adjacent areas in Sri Lanka and Dronning Maud Land, Antarctica permits the recognition of similar crustal blocks and allows the interpretation that the various blocks in Mozambique, Sri Lanka and Antarctica were once part of a mega-nappe, forming part of northern Gondwana, which was thrust-faulted c. 600 km over southern Gondwana during amalgamation of Gondwana at c. 590–550 Ma. The data suggest a deeper level of erosion in southern Africa compared with Antarctica. It is possible that this thrust domain extends, through the Zambezi Belt or Valley, as far west as the Damara Orogen in Namibia with the Naukluft nappes in Namibia, the Makuti Group, the Masoso Suite in the Rushinga area and the Urungwe klippen in northern Zimbabwe, fitting the mega-nappe pattern. Erosional products of the mountain belt are now represented by 700–400 Ma age detrital zircons present in the various sandstone formations of the Transantarctic Mountains, their correlatives in Australia, as well as the Urfjell Group (western Dronning Maud Land) and probably the Natal Group in South Africa.

Fluids (fluorine, chlorine, and OH) in accessory minerals (apatite, titanite and allanite) of Pan-African granitoids (Group-I granitoids, Group-II granitoids and Mefjell Plutonic Complex) from the Sor Rondane Mountains, East Antarctica were precisely measured by an electronic microprobe analyzer in this study. Apatites in the granites have commonly high fluorine contents. However, fluorine contents from the Group-I, Group-II granitoids and Mefjell Plutonic Complex (MPC) are of important variation, which F contents (3.21∼7.20 wt%) in apatite from the Group-II granitoids are much higher than those from the Group-I granitoids (1.22∼3.60 wt%) and the MPC (3.21∼4.11 wt%). Titanite in the MPC has a low fluorine content (0.23∼0.50 wt%), being less than those in the Group-I granitoids (2.28 wt%) and Group-II granitoids (1.85∼2.78 wt%). Fluorine in allanite in the Group-II granitoids seems to have much lower contents than those from the Group-I granitoids and the MPC. Higher fluorine contents in the titanite from the Group-II granitoids may be mainly controlled by late-magmatic fluid-rock interaction processes associated with melt, but may not be indicative of original magma contents based on its petrographic feature. Due to very lower chlorine contents from all of accessory minerals, the authors suggest that titanite and apatite with higher fluorine contents in the Group-II granitoids have much lower H2O (OH) contents compared with those in the Group-I granitoids according to the partition among (F, Cl, OH). Fluorine contents in whole-rock samples show a variation from the higher in the Group-I granitoids to the lower in the Group-II granitoids and the MPC, which are consistent with the changes of those from the biotite and hornblende as well as fluorite occurred in the Group-I granitoids reported previously. Based on the above study of fluorine in accessory minerals and combined with the previous fluorine contents from biotites and hornblendes, the authors suggest that apatites and titanites with higher F contents in the Group-II granitoids and the MPC may not be an indicator of higher fluorine contents in whole-rock, which reflect fluorine contents in magma sources and/or late-thermal activity. Higher fluorine contents in apatite, titanite and allanite may be an additional evidence of A-type affinity.

第6回極域科学シンポジウム[OG] 地圏11月16日（月） 国立極地研究所１階交流アトリウム

Antarctic and Southern Ocean science is vital to understanding natural variability, the processes that govern global change and the role of humans in the Earth and climate system. The potential for new knowledge to be gained from future Antarctic science is substantial. Therefore, the international Antarctic community came together to ‘scan the horizon’ to identify the highest priority scientific questions that researchers should aspire to answer in the next two decades and beyond. Wide consultation was a fundamental principle for the development of a collective, international view of the most important future directions in Antarctic science. From the many possibilities, the horizon scan identified 80 key scientific questions through structured debate, discussion, revision and voting. Questions were clustered into seven topics: i) Antarctic atmosphere and global connections, ii) Southern Ocean and sea ice in a warming world, iii) ice sheet and sea level, iv) the dynamic Earth, v) life on the precipice, vi) near-Earth space and beyond, and vii) human presence in Antarctica. Answering the questions identified by the horizon scan will require innovative experimental designs, novel applications of technology, invention of next-generation field and laboratory approaches, and expanded observing systems and networks. Unbiased, non-contaminating procedures will be required to retrieve the requisite air, biota, sediment, rock, ice and water samples. Sustained year-round access to Antarctica and the Southern Ocean will be essential to increase winter-time measurements. Improved models are needed that represent Antarctica and the Southern Ocean in the Earth System, and provide predictions at spatial and temporal resolutions useful for decision making. A co-ordinated portfolio of cross-disciplinary science, based on new models of international collaboration, will be essential as no scientist, programme or nation can realize these aspirations alone.

The Alfred Wegener Institute for Polar and Marine Research (AWI) has in the past operated two ski equipped aircraft (Dornier Do228-101) for scientific and logistic purposes in polar regions-called POLAR 2 and POLAR 4. Both aircraft are easily able to be adapted to different science programs. Aero-geophysical instrumentation and various atmospheric systems are available. In recent years, a long and fruitful cooperation with the National Institute of Polar Research (NIPR), Tokyo, has been established, whereby so far three joint airborne campaigns have been already performed in the Arctic, namely ASTAR 2000 (Arctic Study of Tropospheric Aerosol and Radiation), AAMP 2002 (Arctic Airborne Measurement Program), and ASTAR 2004. The ANTSYO (Antarctic flight missions at Syowa region: Airborne Geophysical, Glaciological, and Atmospheric Research in East Antarctica) operations of the AWI research aircraft, POLAR 2, started in the season 2005/06, from S17, near Syowa Station in December 2005. Running such surveys presents a logistical challenge that can only be met with the combined support of Alfred Wegener Institute, Bremerhaven, and the NIPR, Tokyo. Therefore, both national Antarctic programs put their logistical capabilities together in order to perform the first extensive airborne missions in this area over a period of three Antarctic summer seasons (2005/06 till 2007/08).

The Sør Rondane Mountains (22°E -28°E ) are located in eastern Dronning Maud Land, East Antarctica, and consist of amphibolite to granulite facies metamorphic rocks and various intrusive rocks. Peak metamorphism took place during the Pan-African event. Considering the mode of occurrence and previously reported age data, felsic magma activity started at the waning stage of the metamorphism. In this study, we report on the petrogenesis of discordantly intruding post-tectonic pyroxene tonalite (Px tonalite) with adakitic composition. In addition, the petrogenesis of posttectonic biotite granite (Bt granite), of which the geochemical features are similar to high-K adakite in the collision zone, are reevaluated with reference to the Px granite. The initial Sr isotopic ratios (SrI) corrected to 525Ma of Px tonalite and Bt granite represent limited values (0.7037-0.7052) that are included within the SrI of the Proterozoic metatonalite corrected to the same age (525Ma). These Sr isotopic signatures combined with geochemical modeling suggest that chemical variation of Px tonalite and Bt granite can be explained by partial melting of the Proterozoic metatonalite with various degrees of melting, leaving garnet as a residual phase, subsequent to fractional crystallization and/or accumulation of specific phases. Taking the tectonic situation and geochemical signature into account, Px tonalite and Bt granite from the Sør Rondane Mountains are correlated to the collision zone adakite and represent the post-collision magmatism in the suture zone during the Gondwana formation of the Pan-African event.

High‐grade gneisses from Mt. Riiser‐Larsen, East Antarctica, have been dated by whole‐rock‐mineral Sm‐Nd and SHRIMP zircon and monazite U‐Pb to help define the thermal history of ultrahigh temperature (UHT) metamorphism in the Napier Complex. Both the monazite and youngest zircon yield a range of apparent ages (∼2.51–2.47 Ga), consistent with crystallization during an extended period of metamorphism. Some zircon also preserves an isotopic record of earlier events, placing an upper limit of a few million years on the duration of peak metamorphic conditions. The similarity of the monazite and zircon U‐Pb ages implies rapid initial postpeak cooling to below the blocking temperature of these minerals (∼900°C). Consistently lower Sm‐Nd whole‐rock‐mineral isochron ages (∼2.38 Ga) indicate that cooling slowed before the temperature reached ∼650°C. The history of the UHT metamorphism is interpreted to be (1) protracted high‐temperature (≥800°C) conditions ∼2.51–2.47 Ga, (2) peak conditions (up to 1100°C)...

Zircons in ultra-high-temperature (UHT) metamorphosed paragneisses from Mt. Riiser-Larsen in the Napier Complex, East Antarctica, were dated by using ion microprobe (SHRIMP) and electron microprobe (EMP). Both SHRIMP and EMP analyses yield consistent 2520–2460 Ma age populations for garnet–orthopyroxene-bearing paragneiss and leucosomes enclosed within. The peak UHT event was dated at 2480 Ma by SHRIMP analyses on metamorphic zircons from the garnet–orthopyroxene paragneiss and those on magmatic zircons from the leucosomes which are interpreted to be formed at syn-UHT. As obtained by SHRIMP, the UHT metamorphic event was terminated no later than 2460 Ma. Minor 2520-Ma SHRIMP age suggests either the onset of prograde metamorphism or another high-grade metamorphic event unrelated to the UHT. EMP analyses on metamorphic zircons from sapphirine–quartz and osumilite-bearing magnesian paragneisses give c. 2500–2450 Ma ages. Inherited igneous zircon cores of the magnesian paragneisses yield relatively scattered EMP ages ranging over c. 3000–2650 Ma, suggesting that igneous materials of these ages sourced the protoliths of the paragneisses and that they were deposited during the interval c. 2650–2520 Ma.

The geological history of Filchnerfjella and surrounding areas (2゜E to 8゜E) in central Dronning Maud Land,East Antarctica,is constructed from metamorphic and igneous petrology,and structural investigations.The geology of Filchner-fjella consists mainly of metamorphic rocks accompanied by intrusive rocks.Two stages of metamorphism can be recognized in this area.The earlier stage metamorphism is defined as a porphyroblast stage (garnet,hornblende,and sillimanite stable), and the later one is recognized as a symplectic stage (orthopyroxene and cordieritestable).Taking metamorphic textures and geothermobarometries into account,the rocks experienced an early high-P/medium-T followed by a low-P and high-T stage. Partial melting took place during the low-P/high-T stage,because probable melt of leucocratic gneiss contains cordierite.The field relationships and petrography of the syenite at Filchnerfjella are similar to those of post-tectonic plutons from central Dronning Maud Land,and most of the post-tectonic intrusive rocks have within-plate geochemical features.The structural history in Filchnerfjella and surrounding areas can be divided into the Pan-African stage and the Meso to Cenozoic stage that relates to the break-up of Gondwana.

Using cathodoluminescence (CL)images,the zircons analyzed by K. Shiraishi et al.(J.Geol.,102,47,1994) for SHRIMP U-Pb dating (prior to the use of CL images) have been re-examined in order to unravel the periods of multiple zircon growth in eastern Dronning Maud Land.In addition four new SHRIMP U-Pb zircon age determinations are presented:two from the Yamato Mountains and two from the Lutzow-Holm Complex (LHC).The major conclusion from this study is that the Grenvillian basement is not ubiquitous in the LHC.Some outcrops are of late Archean-Paleoproterozoic crustal fragments reworked during the Pan-African event. In such cases,there is no indication of a Grenvillian event.Other protoliths are derived from Meso-Neoproterozoic juvenile crust and recycled continental sediments from the margin of the craton.Thus the pre-history of the Pan-African LHC is not uniform.In the Yamato Mountains,two stages of the Pan-African event are suggested,at ~620 Ma and ~535 Ma. These two stages are similar to those recorded in the Sφr Rondane Mountains and central Dronning Maud Land further to the west.These new and revised,updated results provide important constraints on tectonic models for the formation of Gondwana.

The closure temperature of the Rb-Sr whole-rock system for felsic rocks has been generally considered to be ca. 700゜C, but it falls to ca. 400゜C, as a result of efficient action of fluids,especially H_2O. Thus,the Rb-Sr whole-rock ages obtained by rocks collected from a single outcropto specimen-size are not always coincident with those of emplacement of granitic magma or partial melting under high grade metamorphism.Although the Rb-Sr whole-rock isochron ages of metamorphic rocks collected from a wide area have been sometimes interpreted as those of metamorphism,careful consideration for these ages is needed.

The chemical compositions of biotite grains have been determined for early Paleozoic plutonic rocks from the Sor Rondane Mountains, East Antarctica. The plutonic rocks are divided into three groups of the type-I granitoids, type-II granitoids and the Mefjell Plutonic Complex. Two types of biotite are found in the groups: pale yellow to dark green biotite in the type-I granitoids and brown to dark brown biotite in the type-II granitoids and the Mefjell Plutonic Complex. Mineral chemically, biotites from the type-I granitoids have higher SiO2 contents, F contents, and XMg values with lower TiO2 and Cl contents relative to biotites from the type-II granitoids. In the type-II granitoids and the Mefjell Plutonic Complex, biotite strongly enriched in FeO has lower F contents. Biotites in the type-II granitoids and the Mefjell Plutonic Complex have much higher log( f HO 2 )/( fHF) than those from the type-I granitoids. The fluorine content in biotite from the type-I granitoids is similar to that from partial melting A-type granites in Lachlan Fold Belt of eastern Australia; and those from the type-II granitoids and the Mefjell Plutonic Complex are comparable to fractionated aluminous A-type granites from the Lachlan Fold Belt, and the Ambalavayal aluminous Atype granites of South India. Lower fluorine contents in biotite from the type-II granitoids and the Mefjell Plutonic Complex may be mainly controlled by late-magmatic fluid-rock interaction processes associated with melt and may not be indicative of original magma contents. Higher fluorine contents in biotite and whole-rock from the type-I granitoids may reflect fluorine-enriched magmatic source. Our results in biotites from the type-I granitoids as well as geochemistry support the models, which fluorine-rich A-type granites may be derived from partial molten crustal igneous rocks of tonalitic to granodiorite composition.

P-wave velocities (Vp) were measured for nine samples of granulite facies metamorphic rock from the early Paleozoic Liitzow-Holm Complex, East Antarctica. The measurements were done at pressures from 0.1 Gpa to 1.0 Gpa and at temperatures from 25℃ to 400℃ with a piston-cylinder apparatus. Vp values of the ultrabasic-basic granulites range from 6.65 to 7.29 km/s at 1.0 Gpa and 25℃. The felsic gneiss shows nearly constant Vp value from 25℃ to 400℃ at 0.6 and 1.0 Gpa, whereas it exhibits rapid decrease of Vp with increasing temperature at 0.4Gpa. In all rock samples measured, the biotite-two pyroxene granulite shows the strongest negative thermal effect of Vp (0.45 km/s). This strong thermal effect is attributed to relatively higher biotite abundance.

Early Paleozoic granitoids of the S0r Rondane Mountains, which occur as stocks, batholiths or sheets and intrude into late Proterozoic high- to intermediate-grade metamorphic rocks, represent prominent Pan-African to post Pan-African intermediateacidic magmatic events. They are mainly composed of granite and syenite and are enriched in alkalis. Based on geochemical features, there are two types of early Paleozoic granitoids: (1) volcanic-arc type (including Dufek and Lunckeryggen) granitoid, and (2) within-plate type (including Austkampane, Pingvinane, Vikinghogda and Rogerstoppane) granitoid. The volcanic-arc type granitoid has higher Mg#, Sr, and Sr/Ba, Sr/Y, La/Sm, La/Yb and LREE/HREE ratios, lower A/CNK and Ga/Al ratios, and ΣREE with no or positive Eu anomalies. On the other hand, the within-plate type granitoid has relatively higher A/CNK and Ga/Al ratios, and ΣREE, lower Mg#, Sr, and Sr/Ba, Sr/Y, La/Sm, La/Yb and LREE/HREE ratios with moderate to strong negative Eu anomalies. Geochemical characteristics as well as isotopic data of two types of early Paleozoic granitoids indicate two possibilities of their petrogenesis. One is that the volcanic-arc type granitoid may have been derived from deeper parental magma source by process of fractional crystallization with or without assimilation and/or mixing, subsequently, successive fractional crystallization from the same magma source (should be altered components) after assimilation by crustal materials during ascending, to produce the within-plate type granitoid; the other is that they are derived from different source materials and have different processes. The volcanic-arc type granitoid may be derived from partial melting of the Nils Larsen tonalite with minor mixing with, for example, host gneisses, while the within-plate type granitoid is formed by assimilation of crustal materials of host metamorphic rocks by the melt and then fractional crystallization.

Four different types of paragneisses, (1) ordinary pelitic gneiss, (2) sapphirine-bearing aluminous gneiss, (3) osumilite-bearing magnesian gneiss, and (4) quartz-magnetite-rich ferruginous gneiss, occur in the Namaqualand Metamorphic Complex in South Africa. They are examined with respect to their mineral parageneses and mineral chemistries for assessing chemical evolution during high temperature metamorphism. (1) Ordinary pelitic gneisses show amphibolite to granulite facies mineral parageneses composed of biotite, sillimanite, cordierite, garnet and spinel with or without orthopyroxene. Other rock types (2)∿ (4), occurring as layers or blocks in pelitic gneiss, granitic orthogneiss or mafic granulite, show characteristic mineral parageneses : (2) Aluminous gneiss is characterized by quartz-free silica-undersaturated mineral parageneses, and contains porphyroblastic clots of sapphirine-spinel-corundum aggregate. (3) Osumilite-bearing magnesian gneiss is composed mainly of quartz, plagioclase, cordierite and osumilite which is mostly replaced by a fine-grained symplectite of cordierite-K-feldspar-quartz-orthopyroxene. Biotite, spinel and orthopyroxene are minor. (4) Ferruginous gneiss contains a large volume of magnetite accompanying quartz, sillimanite and spinel. Feldspar is typically lacking. Biotite in paragneisses contains a varying amount of fluorine, up to 5.8wt%, having no systematic relation to whether it coexists with orthopyroxene or not. Geothermobarometries for coexisting garnet and orthopyroxene yield metamorphic conditions around 850℃ and 0.5GPa. Orthopyroxene contains high (Al)_2O_3,up to 8.5wt%, and is probably formed by the dehydration melting of biotite at the peak of metamorphism. ZnO contents of spinel in pelitic, ferruginous and magnesian gneisses range from 0.3 to 13.7wt%, whereas those in the sapphirine-bearing aluminous gneisses are less than 0.5wt%.

Cordierite-phlogopite gneiss with spectacular coarse pseudomorphs of sillimanite after andalusite occurs as a kind of Mg-Al-rich rock in the Dabeeb-Hytkoras area of the granulite-faces western Namaqualand Metamorphic Complex. The sillimanite pseudomorphs are always fringed by spinel-cordierite coronas, which, in turn, are surrounded by cordierite mono-mineral zones. The spinel-cordierite coronas include minor amounts of sapphirine, corundum and rutile. The matrix comprises mainly cordierite and phlogopite with minor plagioclase and orthopyroxene plus a trace of quartz. Orthopyroxene is often replaced partially by symplectitic intergrowths of phlogopite and quartz. The modes of occurrence and chemical compositions of minerals indicate that the rock followed a prograde metamorphic P-T path from the andalusite to the sillimanite stability fields and a subsequent isobaric cooling path and that partial melting took place during granulite-facies metamorphism resulting in its present geochemical character.