TY  - JOUR
A1  - Forster, Hans-Jürgen
A1  - Cooper, Mark A.
A1  - Roberts, Andrew C.
A1  - Stanley, Chris J.
A1  - Criddle, Alan J.
A1  - Hawthorne, Frank C.
A1  - Laflamme, J. H. Gilles
A1  - Tischendorf, Gerhard
T1  - Schlemaite, (Cu,square)(6)(Pb,Bi)Se-4, a new mineral species from Niederschlema-Alberoda, Erzgebirge, Germany : Description and crystal structure
N2  - Schlemaite, with the simplified formula (Cu,rectangle)(6)(Pb,Bi)Se-4, is a new mineral species from the Niederschlema-Alberoda vein-type uranium deposit at Hartenstein, Erzgebirge, Germany. It occurs as anhedral to subhedral grains with no obvious forms or twinning, in aggregates of up to several hundred mum across, with berzelianite, eucairite and clausthalite in a dolomite-ankerite matrix. Schlemaite is black with a black streak and opaque with a metallic luster. It is brittle with an uneven fracture and no observable cleavage. It has a mean VHN (25 g load) of 106 kg/mm(2), which roughly equates to a Mobs hardness of 3. In plane-polarized reflected light, schlemaite is grey, non- pleochroic with a very weak bireflectance. It has very weak anisotropy, with rotation tints in shades of very pale metallic orange and blue, and shows no internal reflections. Electron-microprobe analyses yielded a mean composition Cu 38.86, Ag 2.57, An 0.07, Hg 0.09, Pb 13.75, Bi 9.12, Se 35.11, total 99.57 wt.%. The empirical formula (based on 4 Se apfu) is (Cu5.50Ag0.21)(Sigma5.71)(Pb0.60Bi0.39)(Sigma0.99)Se-4. The calculated density is 7.54 g/cm(3) (based on the empirical formula and unit-cell parameters refined from single-crystal data). Schlemaite is monoclinic, P2(1)/m, a 9.5341(8), b 4.1004(3), c 10.2546(8) Angstrom, beta 100.066(2)degrees, V 394.72(9) Angstrom(3), a:b:c 2.3252:1:2.5009, Z = 2. The crystal structure of schlemaite was solved by direct methods and refined to an R index of 4.8% using 1303 unique reflections collected on a four-circle diffractometer equipped with a CCD detector. The structure consists of intercalated ordered and disordered layers. The ordered layer consists of ladders of Ph2+ + Bi3+ coordinated by Se, the former showing strong lone-pair-stereoactive effects, and a network of Cu+ coordinated by Se anions. The disordered layer consists of an array of sites partly occupied by Cu+ and Ag+ in a variety of coordinations, and is characterized by strong short-range order. The strongest seven lines of the X-ray powder-diffraction pattern [d in Angstrom(I)(hkl)] are: 3.189(100)(012), 3.132(100)(112), 2.601(70)(113), 2.505(50)(311), 2.151(60)(014), 2.058(80)(020) and 1.909(50)(314). Although schlemaite is chemically similar to furutobeite, (Cu,Ag)(6)PbS4, it is not isostructural with it. The mineral is named after the Schlema-Alberoda uranium ore field near Schneeberg in the ancient mining region of Saxony, Germany
Y1  - 2003
ER  - 
TY  - JOUR
A1  - Scott, James M.
A1  - Cooper, Alan F.
A1  - Palin, J. Michael
A1  - Tulloch, Andy J.
A1  - Kula, Joseph L.
A1  - Jongens, Richard
A1  - Spell, Terry L.
A1  - Pearson, Norman J.
T1  - Tracking the influence of a continental margin on growth of a magmatic arc, Fiordland, New Zealand, using thermobarometry, thermochronology, and zircon U-Pb and Hf isotopes
N2  - Geothermobarometric, radiogenic isotopic and thermochronologic data are used to track the influence of an ancient continental margin (Western Province) on development of an adjacent Carboniferous-Cretaceous magmatic arc (Outboard Median Batholith) in Fiordland, New Zealand. The data show a record of complicated Mesozoic Gondwana margin growth. Paragneiss within the Outboard Median Batholith is of Carboniferous to Jurassic age and records burial to middle crustal depths in Late Jurassic-Early Cretaceous during subduction-related plutonism and arc thickening. In contrast, Western Province metasedimentary rocks in the area of study immediately west of the Outboard Median Batholith are Late Cambrian-Early Ordovician in age, recrystallized at the amphibolite facies in the Late Devonian-Early Carboniferous and exhibit no evidence for Mesozoic textural or isotopic reequilibration. A phase of deformation, between 128 and 116 Ma deformed, exhumed, and cooled the Outboard Median Batholith to greenschist facies temperatures, while large parts of the Western Province underwent >= 9 kbar metamorphic conditions. Zircon grains from Mesozoic inboard plutons are isotopically more evolved (epsilon Hf(t) = +2.3 to +4.0) than those in the Outboard Median Batholith (epsilon Hf(t) = +9.4 to +11.1). The contrasting zircon Hf isotope ratios, absence of S-type plutons or Proterozoic-Early Paleozoic inherited zircon, and the apparent absence of Early Paleozoic metasedimentary rocks indicates that the Outboard Median Batholith is unlikely to be underlain by the Western Province continental lithosphere. The new data are consistent with the Outboard Median Batholith representing an allochthonous (although not necessarily exotic) arc that was juxtaposed onto the Gondwana continental margin along the intervening Grebe Mylonite Zone.
Y1  - 2009
UR  - http://www.agu.org/journals/tc/
U6  - https://doi.org/10.1029/2009tc002489
SN  - 0278-7407
ER  - 
TY  - JOUR
A1  - Ley-Cooper, Alan Yusen
A1  - Viezzoli, Andrea
A1  - Guillemoteau, Julien
A1  - Vignoli, Giulio
A1  - Macnae, James
A1  - Cox, Leif
A1  - Munday, Tim
T1  - Airborne electromagnetic modelling options and their consequences in target definition
JF  - Exploration geophysics : the bulletin of the Australian Society of Exploration Geophysicists
N2  - Given the range of geological conditions under which airborne EM surveys are conducted, there is an expectation that the 2D and 3D methods used to extract models that are geologically meaningful would be favoured over ID inversion and transforms. We do after all deal with an Earth that constantly undergoes, faulting, intrusions, and erosive processes that yield a subsurface morphology, which is, for most parts, dissimilar to a horizontal layered earth.
 We analyse data from a survey collected in the Musgrave province, South Australia. It is of particular interest since it has been used for mineral prospecting and for a regional hydro-geological assessment. The survey comprises abrupt lateral variations, more-subtle lateral continuous sedimentary sequences and filled palaeovalleys. As consequence, we deal with several geophysical targets of contrasting conductivities, varying geometries and at different depths. We invert the observations by using several algorithms characterised by the different dimensionality of the forward operator.
 Inversion of airborne EM data is known to be an ill-posed problem. We can generate a variety of models that numerically adequately fit the measured data, which makes the solution non-unique. The application of different deterministic inversion codes or transforms to the same dataset can give dissimilar results, as shown in this paper. This ambiguity suggests the choice of processes and algorithms used to interpret AEM data cannot be resolved as a matter of personal choice and preference.
 The degree to which models generated by a ID algorithm replicate/or not measured data, can be an indicator of the data's dimensionality, which perse does not imply that data that can be fitted with a 1D model cannot be multidimensional. On the other hand, it is crucial that codes that can generate 2D and 3D models do reproduce the measured data in order for them to be considered as a plausible solution. In the absence of ancillary information, it could be argued that the simplest model with the simplest physics might be preferred.
KW  - airborne
KW  - electromagnetics
KW  - exploration
KW  - inversion
KW  - target
Y1  - 2015
U6  - https://doi.org/10.1071/EG14045
SN  - 0812-3985
SN  - 1834-7533
VL  - 46
IS  - 1
SP  - 74
EP  - 84
PB  - CSIRO
CY  - Clayton
ER  - 
TY  - JOUR
A1  - Toy, Virginia Gail
A1  - Sutherland, Rupert
A1  - Townend, John
A1  - Allen, Michael J.
A1  - Becroft, Leeza
A1  - Boles, Austin
A1  - Boulton, Carolyn
A1  - Carpenter, Brett
A1  - Cooper, Alan
A1  - Cox, Simon C.
A1  - Daube, Christopher
A1  - Faulkner, D. R.
A1  - Halfpenny, Angela
A1  - Kato, Naoki
A1  - Keys, Stephen
A1  - Kirilova, Martina
A1  - Kometani, Yusuke
A1  - Little, Timothy
A1  - Mariani, Elisabetta
A1  - Melosh, Benjamin
A1  - Menzies, Catriona D.
A1  - Morales, Luiz
A1  - Morgan, Chance
A1  - Mori, Hiroshi
A1  - Niemeijer, Andre
A1  - Norris, Richard
A1  - Prior, David
A1  - Sauer, Katrina
A1  - Schleicher, Anja Maria
A1  - Shigematsu, Norio
A1  - Teagle, Damon A. H.
A1  - Tobin, Harold
A1  - Valdez, Robert
A1  - Williams, Jack
A1  - Yeo, Samantha
A1  - Baratin, Laura-May
A1  - Barth, Nicolas
A1  - Benson, Adrian
A1  - Boese, Carolin
A1  - Célérier, Bernard
A1  - Chamberlain, Calum J.
A1  - Conze, Ronald
A1  - Coussens, Jamie
A1  - Craw, Lisa
A1  - Doan, Mai-Linh
A1  - Eccles, Jennifer
A1  - Grieve, Jason
A1  - Grochowski, Julia
A1  - Gulley, Anton
A1  - Howarth, Jamie
A1  - Jacobs, Katrina
A1  - Janku-Capova, Lucie
A1  - Jeppson, Tamara
A1  - Langridge, Robert
A1  - Mallyon, Deirdre
A1  - Marx, Ray
A1  - Massiot, Cécile
A1  - Mathewson, Loren
A1  - Moore, Josephine
A1  - Nishikawa, Osamu
A1  - Pooley, Brent
A1  - Pyne, Alex
A1  - Savage, Martha K.
A1  - Schmitt, Doug
A1  - Taylor-Offord, Sam
A1  - Upton, Phaedra
A1  - Weaver, Konrad C.
A1  - Wiersberg, Thomas
A1  - Zimmer, Martin
T1  - Bedrock geology of DFDP-2B, central Alpine Fault, New Zealand
JF  - New Zealand journal of geology and geophysics : an international journal of the geoscience of New Zealand, the Pacific Rim, and Antarctica ; NZJG
N2  - During the second phase of the Alpine Fault, Deep Fault Drilling Project (DFDP) in the Whataroa River, South Westland, New Zealand, bedrock was encountered in the DFDP-2B borehole from 238.5–893.2 m Measured Depth (MD). Continuous sampling and meso- to microscale characterisation of whole rock cuttings established that, in sequence, the borehole sampled amphibolite facies, Torlesse Composite Terrane-derived schists, protomylonites and mylonites, terminating 200–400 m above an Alpine Fault Principal Slip Zone (PSZ) with a maximum dip of 62°. The most diagnostic structural features of increasing PSZ proximity were the occurrence of shear bands and reduction in mean quartz grain sizes. A change in composition to greater mica:quartz + feldspar, most markedly below c. 700 m MD, is inferred to result from either heterogeneous sampling or a change in lithology related to alteration. Major oxide variations suggest the fault-proximal Alpine Fault alteration zone, as previously defined in DFDP-1 core, was not sampled.
KW  - Alpine Fault
KW  - New Zealand
KW  - scientific drilling
KW  - mylonite
KW  - cataclasite
Y1  - 2017
U6  - https://doi.org/10.1080/00288306.2017.1375533
SN  - 0028-8306
SN  - 1175-8791
VL  - 60
IS  - 4
SP  - 497
EP  - 518
PB  - Taylor & Francis
CY  - Abingdon
ER  -