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121.
122.
Margaret Wickens Pearce 《The Cartographic journal》2014,51(2):107-122
AbstractThis article presents the cartographic outcome of a 3-year collaboration with Penobscot Nation Cultural & Historic Preservation to map the traditional place names of Penobscot territory in the state of Maine. After a consideration of the challenges of mapping Indigenous place names, I describe my cartographic contribution to the project, to transform the map design using the tools of narrativity and translation. Initial insights about Penobscot place names then led to wider insights regarding Indigenous place names and traditional cartography, through a comparison to similar practices in the place name traditions of other communities. I then explain how these insights influenced the design of the map itself. 相似文献
123.
Using Mg Isotopes to Trace Cyanobacterially Mediated Magnesium Carbonate Precipitation in Alkaline Lakes 总被引:1,自引:0,他引:1
Liudmila S. Shirokova Vasileios Mavromatis Irina A. Bundeleva Oleg S. Pokrovsky Pascale B��n��zeth Emmanuelle G��rard Christopher R. Pearce Eric H. Oelkers 《Aquatic Geochemistry》2013,19(1):1-24
This study assesses the potential use of Mg isotopes to trace Mg carbonate precipitation in natural waters. Salda Lake (SW Turkey) was chosen for this study because it is one of the few modern environments where hydrous Mg carbonates are the dominant precipitating minerals. Stromatolites, consisting mainly of hydromagnesite, are abundant in this lake. The Mg isotope composition of incoming streams, groundwaters, lake waters, stromatolites, and hydromagnesite-rich sediments were measured. Because Salda Lake is located in a closed basin, mass balance requires that the Mg isotopic offset between Lake Salda water and precipitated hydromagnesite be comparable to the corresponding offset between Salda Lake and its water inputs. This is consistent with observations; a ??26Mg offset of 0.8?C1.4??? is observed between Salda Lake water and it is the incoming streams and groundwaters, and precipitated hydromagnesite has a ??26Mg 0.9?C1.1??? more negative than its corresponding fluid phase. This isotopic offset also matches closely that measured in the laboratory during both biotic and abiotic hydrous Mg carbonate precipitation by cyanobacteria (Mavromatis, V., Pearce, C., Shirokova, L. S., Bundeleva, I. A., Pokrovsky, O. S., Benezeth, P. and Oelkers, E.H.: Magnesium isotope fractionation during inorganic and cyanobacteria-induced hydrous magnesium carbonate precipitation, Geochim. Cosmochim. Acta, 2012a. 76, 161?C174). Batch reactor experiments performed in the presence of Salda Lake cyanobacteria and stromatolites resulted in the precipitation of dypingite (Mg5(CO3)4(OH)2·5(H2O)) and hydromagnesite (Mg5(CO3)4(OH)2·4H2O) with morphological features similar to those of natural samples. Concurrent abiotic control experiments did not exhibit carbonate precipitation demonstrating the critical role of cyanobacteria in the precipitation process. 相似文献
124.
Douglas Pearce 《GeoJournal》1989,19(3):250-250
Other papers presented at the meeting will be published in 1989 and 1990 in two special issues of Tourism Recreation Research devoted to North American perspectives on international tourism and International tourism in developing countries. 相似文献
125.
Douglas G. Pearce 《GeoJournal》1993,29(3):225-232
Recent emphasis on the growth in overseas arrivals has overshadowed domestic tourism which, nevertheless, remains a very significant social and economic activity in New Zealand. This paper analyses the geographical dimensions of tourist travel using data from the Domestic Travel Study. Once broad national trends are identified, inter-regional travel patterns are examined using dominant flow analysis and regional profiles are established by means of ternary graphs. This analysis shows the dominance of the major metropolitan markets, the regionalized nature of much domestic tourism and regional variations in visitor profiles. Regional population size plays a major role in determining overall flows but what appears to make the difference between a net loss or gain in total bednights is a region's ability to attract holiday visitors. This underscores the value which the promotion of domestic tourism may have in regional development. 相似文献
126.
R. G. Pearce 《Geophysical Journal International》1981,64(1):187-200
Summary. It is shown that complex teleseismic P waveforms from a shallow earthquake in a tectonic area can be interpreted using a simple source model embedded in a plane layer velocity structure (with sea layer) whose details are based upon independent evidence. This gives hope that structural complexity in tectonic regions may not always make distant P -wave seismograms impossible to interpret, and that, instead, source complexity may be responsible for some of the many complex waveforms observed, even for earthquakes below magnitude m b 5.5. 相似文献
127.
Summary. We describe a method which provides an estimate of the accuracy to which time-domain features of seismic signals can be measured in the presence of noise. Observed seismograms are simulated by adding random noise with the same frequency spectrum and signal-to-noise ratio to matching synthetic seismograms. The effect of noise on synthetic and observed P -wave first motions is used as an illustration. It is shown that the apparent reliability of such observations, as determined by visual estimation, is often illusory. 相似文献
128.
Fault plane solutions using relative amplitudes of P and pP 总被引:1,自引:1,他引:1
R. G. Pearce 《Geophysical Journal International》1977,50(2):381-394
Summary. One way of finding the fault plane orientations of small shallow earthquakes is by the generation of theoretical P -wave seismograms to match those observed at several distant stations. Here, a technique for determining the uniqueness of fault plane solutions computed using the modelling method of Douglas et al . is described. Relative amplitudes of P and pP , and their polarities if unambiguous, are measured on the observed seismograms to be modelled, and appropriate confidence limits are assigned to each measurement. A systematic search is then made for all fault plane orientations which satisfy these observations.
Examples show that if P and pP are not severely contaminated by other arrivals, a well-defined and unique fault plane orientation can often be computed using as few as three stations well distributed in azimuth. Further, even if pP is not identifiable on a particular seismogram, then an upper bound on its amplitude – deduced from the observed coda – still places a significantly greater constraint on the fault plane orientation than would be provided by a P onset polarity alone. Modelling takes account of all such information, and is able to further eliminate incompatible solutions (e.g. by the correct simulation of sP ). It follows that if solutions can be found which satisfy many observed seismograms, this places high significance on the validity of the assumed double-couple source mechanism.
This relative amplitude technique is contrasted with the familiar first motion method of fault plane determination which requires many polarity readings, whose reliabilities are difficult to quantify. It is also shown that fault plane orientations can be determined for earthquakes below the magnitude at which first motion solutions become unreliable or impossible. 相似文献
Examples show that if P and pP are not severely contaminated by other arrivals, a well-defined and unique fault plane orientation can often be computed using as few as three stations well distributed in azimuth. Further, even if pP is not identifiable on a particular seismogram, then an upper bound on its amplitude – deduced from the observed coda – still places a significantly greater constraint on the fault plane orientation than would be provided by a P onset polarity alone. Modelling takes account of all such information, and is able to further eliminate incompatible solutions (e.g. by the correct simulation of sP ). It follows that if solutions can be found which satisfy many observed seismograms, this places high significance on the validity of the assumed double-couple source mechanism.
This relative amplitude technique is contrasted with the familiar first motion method of fault plane determination which requires many polarity readings, whose reliabilities are difficult to quantify. It is also shown that fault plane orientations can be determined for earthquakes below the magnitude at which first motion solutions become unreliable or impossible. 相似文献
129.
130.
Anna Stevenson Jamie Pearce Tony Blakely Vivienne Ivory Karen Witten 《New Zealand geographer》2009,65(3):211-221
Over the past two decades, there has been a resurgence of interest into place‐based influences on health. Researchers have identified that various characteristics of neighbourhoods exert an influence on the health outcomes and behaviours of local residents. Understanding the processes linking places to health provides considerable potential for a range of policy interventions. We review the New Zealand‐based neighbourhoods and health research. Consideration is given to the types of neighbourhood characteristics, as well the range of health outcomes that have been studied. Finally, we suggest some priorities for further research into the mechanisms underpinning neighbourhood influences on health in New Zealand. 相似文献