Geology of El Domo deposit in central Ecuador: a VMS formed on top of an accreted margin     

Cristian Vallejo  Francisco Soria  Fernando Tornos  German Naranjo  Bayardo Rosero  Fredy Salazar  Ryan Cochrane 《Mineralium Deposita》2016,51(3):389-409

  相似文献   

Reflection response for normal incidence probing of vertically nonhomogeneous media     

Vetter  W. Zielinski  A. Cochrane  N. 《Oceanic Engineering, IEEE Journal of》1982,7(3):120-131

A time domain synthetic reflection seismogram is detailed and, as a limiting condition on this model, the analytic reflection impulse response for a one-dimensional lossless acoustic medium with piecewise continuous acoustic impedance is obtained. This analytic impulse response solution, in the structure of a sum of terms by order of reflection, provides insight to some of the poorly understood aspects of acoustic reflections from stratified and smoothly varying media as may be encountered in shallow marine sediments and elsewhere. It offers as well an approach for the inverse problem of extracting acoustic impedance profiles from reflection response data, though other effects (such as wavefront spreading, dispersive and absorptive attenuation, and wavelet broadening attendant with pulse propagation through a medium) need to be accommodated.  相似文献   

Changes in North Sea macrofauna communities and species distribution between 1986 and 2000     

Ingrid KrönckeHenning Reiss  Jacqueline D. EggletonJohn Aldridge  Magda J.N. BergmanSabine Cochrane  Johan A. CraeymeerschSteven Degraer  Nicolas DesroyJean-Marie Dewarumez  Gerard C.A. DuineveldKarel Essink  Hans HillewaertMarc S.S. Lavaleye  Andreas MollStefan Nehring  Richard NewellEivind Oug  Thomas PohlmannEike Rachor  Mike RobertsonHeye Rumohr  Michaela SchratzbergerRebecca Smith  Edward Vanden Berghe  Jan van DalfsenGert van Hoey  Magda VincxWouter Willems  Hubert L. Rees 《Estuarine, Coastal and Shelf Science》2011,94(1):1-15

The North Sea Benthos Project 2000 was initiated as a follow-up to the 1986 ICES North Sea Benthos Survey with the major aim to identify changes in the macrofauna species distribution and community structure in the North Sea and their likely causes.The results showed that the large-scale spatial distribution of macrofauna communities in the North Sea hardly changed between 1986 and 2000, with the main divisions at the 50 m and 100 m depth contours. Water temperature and salinity as well as wave exposure, tidal stress and primary production were influential environmental factors on a large (North Sea-wide) spatial scale.The increase in abundance and regional changes in distribution of various species with a southern distribution in the North Sea in 2000 were largely associated with an increase in sea surface temperature, primary production and, thus, food supply. This can be most likely related to the North Sea hydro-climate change in the late 1980s influenced by the variability in the North Atlantic Oscillation (NAO). Only one cold-temperate species decreased in abundance in 2000 at most of the stations. Indications for newly established populations of offshore non-native species were not found.Differences in macrofauna community structure on localised spatial scales were predominantly found north of the 50 m depth contour off the British coast along the Flamborough Head Front towards the Dogger Bank, off the coast of Jutland and at the Frisian Front. These changes were most likely attributed to stronger frontal systems in 2000 caused by the increased inflow of Atlantic water masses in relation to the hydro-climate change in the late 1980s.  相似文献   

AN APPLICATION OF CLOSE RANGE PHOTOGRAMMETRY IN SHIPBUILDING     

J. Cochrane 《The Photogrammetric Record》1989,13(73):63-67

A test was devised to measure the distortion of a ship section during and after a crane lift. As the shipbuilders expend significant man hours and costs in carrying out adjustments to fit ship sections together after lifting, it was hoped that information gained from the test could be used to make design adjustments to ensure a better fit. The test was carried out by BKS Surveys Ltd. and Harland and Wolff Ltd., the Belfast shipbuilders.  相似文献   

Searching for social justice in GIScience publications     

Logan Cochrane  Jon Corbett  Mike Evans 《制图学和地理信息科学》2017,44(6):507-520

ABSTRACT

Maps are explicitly positioned within the realms of power, representation, and epistemology; this article sets out to explore how these ideas are manifest in the academic Geographic Information Science (GIScience) literature. We analyze 10 years of literature (2005–2014) from top tier GIScience journals specific to the geoweb and geographic crowdsourcing. We then broaden our search to include three additional journals outside the technical GIScience journals and contrast them to the initial findings. We use this comparison to discuss the apparent technical and social divide present within the literature. Our findings demonstrate little explicit engagement with topics of social justice, marginalization, and empowerment within our subset of almost 1200 GIScience papers. The social, environmental, and political nature of participation, mapmaking, and maps necessitates greater reflection on the creation, design, and implementation of the geoweb and geographic crowdsourcing. We argue that the merging of the technical and social has already occurred in practice, and for GIScience to remain relevant for contributors and users of crowdsourced maps, researchers and practitioners must heed two decades of calls for substantial and critical engagement with the geoweb and crowdsourcing as social, environmental, and political processes.  相似文献   

MT. WILHELM STUDIES I. THE ALPINE AND SUBALPINE VEGETATION. By L. K. Wade and D. N. McVean.     

G. Ross  Cochrane 《New Zealand geographer》1971,27(1):95-96

  相似文献   

Electrical Conductivity Structure by Geomagnetic Induction at the Continental Margin of Atlantic Canada     

R. D. Hyndman  N. A. Cochrane 《Geophysical Journal International》1971,25(5):425-446

  相似文献   

Erts-II and Resource Management in New Zealand     

G. Ross Cochrane 《New Zealand geographer》1975,31(2):178-185

  相似文献   

The Politics of AIDS Surveillance     

Michelle Cochrane 《The Professional geographer》2000,52(2):205-218

This paper examines the social construction of official HIV/AIDS surveillance data in San Francisco and the implications of this research for understanding the past and future trajectories of the epidemic in the United States. I employ a methodology of social constructivism in an analysis of the historical evolution of the epidemic and a critique of its quantitative representation by public health officials. I argue that medical geographers have erroneously interpreted AIDS surveillance data as evidence for an exponential growth in AIDS cases during the past 17 years, neglecting to critically explore the multiple and extensive revisions in the definition of the disease (in 1982, 1985, 1987, 1993) by which patients have been reported over time. In contrast, social constructivism exemplifies a method for elucidating the sociopolitical interests of public health institutions and community activists which underlie the constant metamorphosis of the subjects (e.g., patients) and object (e.g., ‘AIDS’) comprising this epidemic.  相似文献   

A study of the infiltration characteristics of undisturbed soil under simulated rainfall     

Harold T. Johnston  Elsayed M. Elsawy  Stanley R. Cochrane 《地球表面变化过程与地形》1980,5(2):159-174

Infiltration is the single most important parameter in deriving the net quick response rainfall which contributes to stream flood discharges. Rainfall simulation is used to study the infiltration characteristics in a typical catchment, the Six Mile Water in N. Ireland. The design of the simulator was such that it could be easily moved from one test area to another within the catchment to examine the effect of soil and slope variation. The simulator was first calibrated in controlled laboratory conditions and later the calibration was checked in the field. The simulator was mounted over an undisturbed plot of 37 m² and the surface runoff from the area measured by means of a collecting channel located along a lower edge of the plot. Soil moisture variations were monitored using a soil moisture neutron probe. Soil classification tests and gravimetric moisture contents were carried out on each plot. The field tests were carried out with variations in rainfall intensity, initial conditions, changing seasons, and for different plots within the catchment area. The results obtained are unique in that they present data obtained under field conditions for undisturbed soil within a natural catchment. The infiltration behaviour was found to depend upon rainfall intensity, initial conditions of the plot under consideration, seasonal temperature, and a slope of the plot. The data showed that while a classical Horton type equation for infiltration was suitable for the later stages of each test result when significant surface runoff was taking place, the model failed to represent early response adequately due to storage effects being omitted in the equation. A modified form of Horton equation is proposed, which models more accurately the infiltration characteristics of the full period of each test run.  相似文献