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Detrital Zircon Sedimentary Provenance Ages For The Eoarchaean Isua Supracrustal Belt Southern West Greenland: Juxtaposition Of An Imbricated Ca. 3700 Ma Juvenile Arc Against An Older Complex With 3920-3760 Ma Components, Allen P. Nutman, Clark R L Friend, Shane Paxton
Detrital Zircon Sedimentary Provenance Ages For The Eoarchaean Isua Supracrustal Belt Southern West Greenland: Juxtaposition Of An Imbricated Ca. 3700 Ma Juvenile Arc Against An Older Complex With 3920-3760 Ma Components, Allen P. Nutman, Clark R L Friend, Shane Paxton
Faculty of Science - Papers (Archive)
The amphibolite facies Eoarchaean Isua supracrustal belt (northern part of the Nuuk region, southern West Greenland) is dominated by strongly deformed metabasalts, with chert, banded iron formation, felsic volcanic and volcano-sedimentary rocks and minor gabbro and sedimentary carbonates. It comprises a suture zone between a northern terrane formed at ca. 3700 Ma and a southern one formed at ca. 3800 Ma. At the junction between these two terranes is a strongly tectonised, thin unit of metachert, BIF and carbonate-bearing rocks with minor detrital components, named the dividing sedimentary unit. Away from the belt, the northern terrane is dominated by ca. …
Eoarchaean Crustal Growth In West Greenland (Itsaq Gneiss Complex) And In Northeastern China (Anshan Area): Review And Synthesis, Allen P. Nutman, Vickie C. Bennett, Clark R L Friend, Frances Jenner, Yusheng Wan, Dunyi Liu
Eoarchaean Crustal Growth In West Greenland (Itsaq Gneiss Complex) And In Northeastern China (Anshan Area): Review And Synthesis, Allen P. Nutman, Vickie C. Bennett, Clark R L Friend, Frances Jenner, Yusheng Wan, Dunyi Liu
Faculty of Science - Papers (Archive)
Eoarchaean crust in West Greenland (the Itsaq Gneiss Complex, 3870-3600 Ma) is >80% by volume orthogneisses derived from plutonic tonalite-trondhjemite-granodiorite (TTG) suites,3850, c. 3810 and c. 3710 Mahave some compositional similarities to modern island arc basalts (IAB), suggesting their origin by hydrous fluxing of a suprasubduction-zone upper mantle wedge. Most of the Eoarchaean tonalites match in composition high-silica, low-magnesian adakites, whose petrogenesis is dominated by partial melting of garnetiferous mafic rocks at high pressure. However, associated with the tonalites are volumetrically minor more magnesian quartz diorites, whose genesis probably involved melting of depleted mantle to which some slab-derived component had …
In Situ U-Pb, O And Hf Isotopic Compositions Of Zircon And Olivine From Eoarchaean Rocks, West Greenland: New Insights To Making Old Crust, Joe Hiess, Vickie C. Bennett, Allen P. Nutman, Ian S. Williams
In Situ U-Pb, O And Hf Isotopic Compositions Of Zircon And Olivine From Eoarchaean Rocks, West Greenland: New Insights To Making Old Crust, Joe Hiess, Vickie C. Bennett, Allen P. Nutman, Ian S. Williams
Faculty of Science - Papers (Archive)
The sources and petrogenetic processes that generated some of the Earth's oldest continental crust have been more tightly constrained via an integrated, in situ (U-Pb, O and Hf) isotopic approach. The minerals analysed were representative zircon from four Eoarchaean TTG tonalites and two felsic volcanic rocks, and olivine from one harzburgite/dunite of the Itsaq Gneiss Complex (IGC), southern West Greenland. The samples were carefully chosen from localities with least migmatisation, metasomatism and strain. Zircon was thoroughly characterized prior to analysis using cathodoluminescence, scanning electron, reflected and transmitted light imaging. The zircon from all but one sample showed only minor post-magmatic …
Discovery Of A Non-Peptidic Inhibitor Of West Nile Virus Ns3 Protease By High-Throughput Docking, Dariusz Ekonomiuk, Xun-Cheng Su, Kiyoshi Ozawa, Chrisophe Bodenreider, Siew Pheng Lim, Zheng Yin, Thomas H. Keller, David Beer, Viral Patel, Gottfried Otting, Amedeo Calflisch, Danzhi Huang
Discovery Of A Non-Peptidic Inhibitor Of West Nile Virus Ns3 Protease By High-Throughput Docking, Dariusz Ekonomiuk, Xun-Cheng Su, Kiyoshi Ozawa, Chrisophe Bodenreider, Siew Pheng Lim, Zheng Yin, Thomas H. Keller, David Beer, Viral Patel, Gottfried Otting, Amedeo Calflisch, Danzhi Huang
Faculty of Science - Papers (Archive)
No abstract provided.
Nmr Study Of Complexes Between Low Molecular Mass Inhibitors And The West Nile Virus Ns2b-Ns3 Protease, X Su, Kiyoshi Ozawa, Hiromasa Yagi, S P. Lim, D Wen, D Ekonomiuk, D Huang, T Keller, S Sonntag, A Caflisch, S G. Vasudevan, G Otting
Nmr Study Of Complexes Between Low Molecular Mass Inhibitors And The West Nile Virus Ns2b-Ns3 Protease, X Su, Kiyoshi Ozawa, Hiromasa Yagi, S P. Lim, D Wen, D Ekonomiuk, D Huang, T Keller, S Sonntag, A Caflisch, S G. Vasudevan, G Otting
Faculty of Science - Papers (Archive)
The two-component NS2B-NS3 protease of West Nile virus is essential for its replication and presents an attractive target for drug development. Here, we describe protocols for the high-yield expression of stable isotope-labelled samples in vivo and in vitro. We also describe the use of NMR spectroscopy to determine the binding mode of new low molecular mass inhibitors of the West Nile virus NS2B-NS3 protease which were discovered using high-throughput in vitro screening. Binding to the substrate-binding sites S1 and S3 is confirmed by intermolecular NOEs and comparison with the binding mode of a previously identified low molecular mass inhibitor. Our …
Nmr Analysis Of The Dynamic Exchange Of The Ns2b Cofactor Between Open And Closed Conformations Of The West Nile Virus Ns2b-Ns3 Protease, X Su, Kiyoshi Ozawa, R Qi, S G. Vasudevan, S P. Lim, G Otting
Nmr Analysis Of The Dynamic Exchange Of The Ns2b Cofactor Between Open And Closed Conformations Of The West Nile Virus Ns2b-Ns3 Protease, X Su, Kiyoshi Ozawa, R Qi, S G. Vasudevan, S P. Lim, G Otting
Faculty of Science - Papers (Archive)
Background: The two-component NS2B-NS3 proteases of West Nile and dengue viruses are essential for viral replication and established targets for drug development. In all crystal structures of the proteases to date, the NS2B cofactor is located far from the substrate binding site (open conformation) in the absence of inhibitor and lining the substrate binding site (closed conformation) in the presence of an inhibitor. Methods: In this work, nuclear magnetic resonance (NMR) spectroscopy of isotope and spin-labeled samples of the West Nile virus protease was used to investigate the occurrence of equilibria between open and closed conformations in solution. Findings: In …
2635 Ma Amphibolite Facies Gold Mineralisation Near A Terrane Boundary (Suture?) On Storo, Nuuk Region, Southern West Greenland, Allen P. Nutman, Ole Christiansen, Clark R. L Friend
2635 Ma Amphibolite Facies Gold Mineralisation Near A Terrane Boundary (Suture?) On Storo, Nuuk Region, Southern West Greenland, Allen P. Nutman, Ole Christiansen, Clark R. L Friend
Faculty of Science - Papers (Archive)
Gold on Storø (in the Nuuk region of southern West Greenland) occurs in a slice of strongly deformed, amphibolite facies, Neoarchaean quartzo-feldspathic metasedimentary rocks and amphibolites in tectonic contact with the Eoarchaean Færingehavn terrane and the Meso- to Neoarchaean Akia terrane. The gold is associated with either löllingite (FeAs) + arsenopyrite or pyrrhotite, which belong with the amphibolite facies silicate mineral assemblages. Zircons were U/Pb dated by SHRIMP to constrain the timing of mineralisation. The 2700–2830 Ma oscillatory-zoned, high Th/U volcano-sedimentary zircon as whole grains and cores are interpreted to give the maximum depositional age of the rocks hosting the …
An Alternative Approach To Coal Mine Site Water Management: A Case Study On West Cliff Colliery, Antony Volcich, Stephen A. Short, Adrian C. Hutton, Robert John Morrison
An Alternative Approach To Coal Mine Site Water Management: A Case Study On West Cliff Colliery, Antony Volcich, Stephen A. Short, Adrian C. Hutton, Robert John Morrison
Faculty of Science - Papers (Archive)
The provision of water supply, its usage and discharge, are major concerns for all mines, often accounting for a significant portion of the daily running costs. To reduce these costs, mines will collect as much site runoff as possible, and recycle the water whenever economically feasible. The constant recycling of on-site waters can mean that, over time, the levels of salinity, acidity or alkalinity, or other contaminants may build up within the internal water management system to a point which may lead to problems with licensed discharge requirements. This project investigated the water quality at West Cliff Colliery, in order …
The Itsaq Gneiss Complex Of Southern West Greeland And The Construction Of Eoarchaean Crust At Convergent Plate Boundaries, Allen P. Nutman, Clark R. L Friend, Kenji Horie, Hiroshi Hidaka
The Itsaq Gneiss Complex Of Southern West Greeland And The Construction Of Eoarchaean Crust At Convergent Plate Boundaries, Allen P. Nutman, Clark R. L Friend, Kenji Horie, Hiroshi Hidaka
Faculty of Science - Papers (Archive)
The ca. 3000 km2ItsaqGneissComplex of the Nuuk region, southernWestGreenland was the first body of pre-3600 Ma crust discovered. Such ancient gneisses are now also known elsewhere, but in total form only about a millionth of the modern crust. The other 99.9999% of ancient crust was destroyed by melting and erosion over billions of years. Understanding the origin of this oldest crust is hampered by metamorphism (repeatedly) in the amphibolite or granulite facies, and most of it having been strongly deformed. The ItsaqGneissComplex is dominated by polyphase grey gneisses derived from several suites of tonalites, granites and subordinate quartz-diorites and ferro-gabbros …
Age, Petrogenesis And Metamorphism Of The Syn-Collisional Proven Igneous Complex, West Greenland, Kristine Thrane, J Baker, J Connelly, Allen Phillip Nutman
Age, Petrogenesis And Metamorphism Of The Syn-Collisional Proven Igneous Complex, West Greenland, Kristine Thrane, J Baker, J Connelly, Allen Phillip Nutman
Faculty of Science - Papers (Archive)
The Paleoproterozoic Prøven Igneous Complex (PIC) in West Greenland extends from ca. 72°15′ to 73°10′N, approximately 500 km north of the subduction-related intrusive complex in the core of the +1100 km wide, asymmetric collisional Nagssugtoqidian-Rinkian Orogen. A new U-Pb SHRIMP age for the PIC of 1869±9 Ma indicates that it intruded synchronously with the main collisional phase of the orogen into the passive margin side of the collision. Sm-Nd and Lu-Hf isotopic and A-type geochemical signatures are compatible with its derivation from melted Archean lower crustal material contaminated to varying degrees by pelitic sedimentary rocks of the Karrat Group. The …
New Pieces To The Archaean Terrane Jigsaw Puzzle In The Nuuk Region, Southern West Greeland: Steps In Transforming A Simple Insight Into A Complex Regional Tectonothermal Model, Clark R L Friend, Allen Phillip Nutman
New Pieces To The Archaean Terrane Jigsaw Puzzle In The Nuuk Region, Southern West Greeland: Steps In Transforming A Simple Insight Into A Complex Regional Tectonothermal Model, Clark R L Friend, Allen Phillip Nutman
Faculty of Science - Papers (Archive)
In the south of the Nuuk region of West Greenland our 1980s mapping recognized four Archaean gneiss terranes (Færingehavn, Tre Brødre, Tasiusarsuaq and Akia terranes) with different protolith ages and separate early tectonothermal histories. Later in the Archaean these were juxtaposed and then experienced the same 2700-2500 Ma tectonothermal events. Here we abandon extrapolation of only these four terranes across the whole region, and distinguish two new terranes in the NE. The northernmost Isukasia terrane (previously regarded as the northernmost exposure of the Færingehavn terrane) consists of Palaeoarchaean rocks (>3600 Ma) tectonically bounded on its south by the 3075-2960 …
Complex 3670-3500 Ma Orogenic Episodes Superimposed On Juvenile Crust Accreted Between 3850 And 3690 Ma, Itsaq Gneiss Complex, Southern West Greenland, Clark R L Friend, Allen Phillip Nutman
Complex 3670-3500 Ma Orogenic Episodes Superimposed On Juvenile Crust Accreted Between 3850 And 3690 Ma, Itsaq Gneiss Complex, Southern West Greenland, Clark R L Friend, Allen Phillip Nutman
Faculty of Science - Papers (Archive)
The Itsaq Gneiss Complex of the Nuuk region, southern West Greenland, is dominated by 3850-3690 Ma tonalites intruded into and intercalated with lesser amounts of different ≥3850-3700 Ma supracrustal units. Published wholerock Sr and Nd isotopic studies demonstrate that the tonalites are juvenile crustal additions from a depleted mantle source. From our field studies and SHRIMP U/Pb zircon dating, we argue that this juvenile crustal accretion was spread over ca. 170 m.yr. (≥3850-3690 Ma). Following 3850-3690 Ma juvenile crustal accretion events, the evolution of the Itsaq Gneiss Complex continued with numerous crustal-reworking events between 3670 and 3500 Ma. Examples of …
Macrochannels And Their Significance For Flood-Risk Minimisation, West Dapto, New South Wales, E. L. Roper, Ivars Reinfelds, Gerald C. Nanson
Macrochannels And Their Significance For Flood-Risk Minimisation, West Dapto, New South Wales, E. L. Roper, Ivars Reinfelds, Gerald C. Nanson
Faculty of Science - Papers (Archive)
A prominent characteristic of streams draining catchments in West Dapto, New South Wales, are well developed macrochannels that have formed within alluvial terraces in mid-catchment zones. A detailed hydraulic modelling study using HEC-RAS, HEC-GeoRAS and Arcview GIS indicates that these macrochannels are scaled to accommodate high magnitude floods. They offer a significant degree of natural protection from flood events up to and in excess of 100 years recurrence interval, essentially by operating as 'bankfull' channels during such events. Macrochannel landforms can be clearly distinguished and mapped on fine-scale digital elevation models (DEMs) and other GIS data sources such as rectified …