A Note on Ice Island WH-5

As reported by Hattersley-Smith, Ice Island WH-5, the easternmost and largest (approximately 20 by 9 km.) of the islands resulting from the massive calving of the Ward Hunt Ice Shelf during the winter 1961-2, drifted eastward, whereas the other four islands drifted westward. WH-5, tracked through radar photography by the U.S. Navy "Birdseye" ice reconnaissance flights, continued its eastward movement during the winter 1962-3. It entered the Lincoln Sea, moved south through Robeson Channel and between February 24 and 28, 1963 became lodged across Kennedy Channel, with one end resting against the shore of Ellesmere Island and the other end held by mid-channel Hans Island. In this position the ice island formed an effective barrier to the southward movement of sea-ice from the Arctic Ocean. Open water soon appeared south of the obstruction and by May extended well into Kane Basin. In a study of WH-5 during the summer of 1963 emphasis was placed on physical oceanography, both to observe the local influence of the ice island and to take advantage of the unusual presence of open water in an area where ice normally restricts ship operations. The study was directed by D. C. Nutt and L. K. Coachman and was sponsored by the Arctic Institute with support from the U.S. Office of Naval Research and the U.S. Coast Guard and the collaboration of the Woods Hole Oceanographic Institution, the U.S. Naval Oceanographic Office, the U.S. Military Sea Transportation Service and the U.S. Air Force at Thule, Greenland. ... This brief note, based only on data immediately available, is being published to provide timely information on the recent drift and break-up of ice island WH-5. A more comprehensive report will follow. ..

Self-consistent solution of the Schwinger-Dyson equations for the nucleon and meson propagators

The Schwinger-Dyson equations for the nucleon and meson propagators are solved self-consistently in an approximation that goes beyond the Hartree-Fock approximation. The traditional approach consists in solving the nucleon Schwinger-Dyson equation with bare meson propagators and bare meson-nucleon vertices; the corrections to the meson propagators are calculated using the bare nucleon propagator and bare nucleon-meson vertices. It is known that such an approximation scheme produces the appearance of ghost poles in the propagators. In this paper the coupled system of Schwinger-Dyson equations for the nucleon and the meson propagators are solved self-consistently including vertex corrections. The interplay of self-consistency and vertex corrections on the ghosts problem is investigated. It is found that the self-consistency does not affect significantly the spectral properties of the propagators. In particular, it does not affect the appearance of the ghost poles in the propagators.Comment: REVTEX, 7 figures (available upon request), IFT-P.037/93, DOE/ER/40427-12-N9

Interpretation of Fracture Toughness and R-Curve Behavior by Direct Observation of Microfracture Process in Ti-Based Dendrite-Containing Amorphous Alloys

Fracture properties of Ti-based amorphous alloys containing ductile beta dendrites were explained by directly observing microfracture processes. Three Ti-based amorphous alloys were fabricated by adding Ti, Zr, V, Ni, Al, and Be into a Ti-6Al-4V alloy by a vacuum arc melting method. The effective sizes of dendrites varied from 63 to 104 mu m, while their volume fractions were almost constant within the range from 74 to 76 pct. The observation of the microfracture of the alloy containing coarse dendrites revealed that a microcrack initiated at the amorphous matrix of the notch tip and propagated along the amorphous matrix. In the alloy containing fine dendrites, the crack propagation was frequently blocked by dendrites, and many deformation bands were formed near or in front of the propagating crack, thereby resulting in a zig-zag fracture path. Crack initiation toughness was almost the same at 35 to 36 MPaaem within error ranges in the three alloys because it was heavily affected by the stress applied to the specimen at the time of crack initiation at the crack tip as well as strength levels of the alloys. According to the R-curve behavior, however, the best overall fracture properties in the alloy containing fine dendrites were explained by mechanisms of blocking of the crack growth and crack blunting and deformation band formation at dendrites. (C) The Minerals, Metals & Materials Society and ASM International 2015ope

A reconnaissance geochemical survey of Anglesey

A reconnaissance geochemical survey of Anglesey was based on a drainage survey (at one sample per km2 ) supplemented by low-density soil sampling. A field survey of known mineralisation was carried out to aid data interpretation and assessment of mineral potential. The reconnaissance field survey indicated that the non-ferrous mineralisation of Anglesey may be divided into three groups: (a) copper, (b) copper (lead, zinc) and (c) baryte (lead). Economically, group (b) is the most important and its occurrence is virtually confined to the Lower Palaeozoic rocks. Groups (a) and (c) are small vein occurrences, within the Mona Complex and adjacent to the basal Carboniferous unconformity respectively. The drainage survey encountered major difficulties from the lack of surface drainage, contamination , subdued topography, variable background geology and extensive drift deposits. At least 35% of the island was not effectively covered by the drainage sampling but this figure was reduced by the collection of soil samples from three areas of poor drainage and thin drift cover. Problems were further countered by collecting water, stream sediment and panned concentrate samples at all drainage sites, mineralogically examining anomalous concentrates, and resampling streams with sites found to be contaminated. 440 drainage sites were sampled. Cu, Pb, Zn, Ba, Fe, Mn, Co, Ni and MO were determined in sediment samples and Cu, Pb, Zn, Ba, Fe,Mn, Ti, Ni, Sn, Sb and Ca in panned concentrates. Cu, Pb and Zn were determined in soil and water samples. Large-scale regional variation of the drainage results was examined using computer-generated greyscale maps. Variation was related to bedrock geology, mineralisation and contamination. The comparison of statistical analyses and mineralogical observations indicated that all high Sn and Sb levels were related to contamination and that, in this area, factor analysis was an effective means of discriminating between anomalies caused by contamination and those due to mineralisation. Inter-element relationships also indicated the presence of two chemically distinct types of mineralisation : a Cu-Pb-Zn-Fe sulphide type and a Ba type, which correspond to groups (a + b) and (c) of those defined by the field survey. Threshold levels were established using cumulative frequency plots, and eighteen anomalous areas related to sulphide or baryte mineralisation were delineated. Four of these, at Carmel Head, Llandyfrydog, City Dulas and Llanbadrig were the subject of further study. Other areas considered worthy of investigation are the basal Carboniferous between Dulas and Malltreath, the Gwna rocks around Cerrigceinwen, and the area east of Parys Mountain; the latter area has been investigated by mining companies without success. Further areas not adequately covered by the survey, for example the basic rocks around Rhoscolyn, may also be worthy of further consideration

A Note on Ice Island WH-5

As reported by Hattersley-Smith, Ice Island WH-5, the easternmost and largest (approximately 20 by 9 km.) of the islands resulting from the massive calving of the Ward Hunt Ice Shelf during the winter 1961-2, drifted eastward, whereas the other four islands drifted westward. WH-5, tracked through radar photography by the U.S. Navy "Birdseye" ice reconnaissance flights, continued its eastward movement during the winter 1962-3. It entered the Lincoln Sea, moved south through Robeson Channel and between February 24 and 28, 1963 became lodged across Kennedy Channel, with one end resting against the shore of Ellesmere Island and the other end held by mid-channel Hans Island. In this position the ice island formed an effective barrier to the southward movement of sea-ice from the Arctic Ocean. Open water soon appeared south of the obstruction and by May extended well into Kane Basin. In a study of WH-5 during the summer of 1963 emphasis was placed on physical oceanography, both to observe the local influence of the ice island and to take advantage of the unusual presence of open water in an area where ice normally restricts ship operations. The study was directed by D. C. Nutt and L. K. Coachman and was sponsored by the Arctic Institute with support from the U.S. Office of Naval Research and the U.S. Coast Guard and the collaboration of the Woods Hole Oceanographic Institution, the U.S. Naval Oceanographic Office, the U.S. Military Sea Transportation Service and the U.S. Air Force at Thule, Greenland. ... This brief note, based only on data immediately available, is being published to provide timely information on the recent drift and break-up of ice island WH-5. A more comprehensive report will follow. ..

A reconnaissance geochemical survey of Anglesey

SIGLELD:5779.77(IGS-MRPR--51). / BLDSC - British Library Document Supply CentreGBUnited Kingdo

Base-metal and gold mineralisation in north-west Angelsey, North Wales

SIGLEAvailable from British Library Document Supply Centre- DSC:5779.77(BGS-MRPR--99) / BLDSC - British Library Document Supply CentreGBUnited Kingdo