PLACE INVADERS: CONSTRUCTING THE NOMADIC THREAT IN ENGLAND*

Over the centuries, the image of nomads threatening sedentary ways of life has been a common pejorative representation. In order to understand what geographies underpin narratives about nomads, I examine how social theory and media representations invoke the image of nomads. Both media and academic representations are buttressed by limited understandings of place and space, framing nomads as the quintessential “place invaders.” Focusing on nomadic Gypsies and Travelers in England provides a contemporary example of this process. British media representations construct nomadic Gypsies and Travelers in England as out‐of‐place and threatening. Deconstructing essentialist geographical conceptions allows us to avoid reproducing the common image of placeless nomads, reveals how people utilize place to render others inferior, and highlights the fact that conflicts between nomadic and sedentary ways of life are not intractable and natural. Adopting a more nuanced understanding of place can challenge the dominant trope of nomads as place invaders.     

The relationship between basin and margin thermal evolution assessed by fission track thermochronology: an application to offshore southern Norway

Abstract We use a quantitative model of apatite fission track (AFT) annealing to constrain the thermal evolution of a sedimentary basin and its margin. Apatites deposited in a basin contain several types of information. Provided temperatures remained below ?70°C, they retain much of their provenance thermal signatures and mainly record the thermal evolution of their source area. Above 70°C, the fission tracks in apatite rapidly fade, reflecting the thermal evolution of the basin. Therefore, downhole AFT dates in a well section can in principle be used to assess both the provenance detail (from shallow/cool samples) and the subsequent thermal history in the basin (from the deeper samples). We apply this concept to the south Norwegian offshore and onshore using AFT and ZFT (zircon fission track) data; the latter constrain maximum palaeotemperatures and provide additional provenance information. AFT and ZFT data from three offshore wells in the northern North Sea are shown to contain a record of palaeogeographical and tectonic evolution, closely associated with the Norwegian basement. ZFT data from Middle Triassic sediments suggest a Permian volcanic source. Modelling of AFT data from Jurassic sediments presently residing at temperatures below 70°C indicate rapid cooling during the Late Triassic to Early Jurassic, similar to onshore AFT data. During the Cretaceous minor sediment supply was derived from the Norwegian basement, as evidenced by ZFT ages that do not correlate to the onshore, suggesting that parts of southern Norway were covered with sediments at this time. At the end of the Palaeogene and during the Neogene, the south Norwegian basement again became a major source of elastics. AFT and ZFT data indicate that all wells are presently at maximum temperatures. No significant (> 500 m) erosion events are indicated in the three wells since the Jurassic. AFT data have not yet effectively equilibrated to present-day temperatures as nonzero fission track ages are maintained in sediments currently at temperatures of > 120°C. This implies that the present-day thermal regime has only recently been installed. Probable causes include rapid subsidence and an increase in the geothermal gradient during the last 5 Myr.     

Assessing participatory GIS for community-based natural resource management: claiming community forests in Cameroon

This paper critically reviews and analyses participatory GIS (PGIS) and participatory mapping applications within participatory spatial planning for community-based natural resource management in developing countries. There is an often implicit assumption that PGIS use is effective, in that it meets content needs, satisfies underlying local stakeholder interests and therefore is a tool for better governance. The analytical framework looks at participatory spatial planning performance with respect to key dimensions of governance, especially the intensity of community participation and empowerment, equity within communities and between 'governed' and 'governing', respect for indigenous knowledge, rights, ownership, legitimacy, and effectiveness. Specific development focus is given by a case study using participatory mapping and PGIS in community forest legitimization, planning and management in Tinto, Cameroon. 'Good governance' criteria are applied ex-post to the implementation procedures, the geo-information outputs, and the longer-term outcomes of the PGIS processes. Impacts of incorporating PGIS were examined in terms of the types and degrees of participation in the process; access to, and the uses made of, the geographic information; whether the information outputs met stakeholders' requirements; and the overall changes in equity and empowerment in the community. It was found that PGIS/participatory mapping processes contributed – positively, though not comprehensively – to good governance, by improving dialogue, redistributing resource access and control rights – though not always equitably – legitimizing and using local knowledge, exposing local stakeholders to geospatial analysis, and creating some actor empowerment through training. PGIS promoted empowerment by supporting community members' participation in decision-making and actions, and by enabling land use planning decisions beyond community forestry itself.     

Reaction Between Ultramafic Rock and Fractionating Basaltic Magma II. Experimental Investigation of Reaction Between Olivine Tholeiite and Harzburgite at 1150-1050?C and 5 kb

We present results of experiments on mixtures of olivine tholeiiteand mantle harzburgite, at 5 kb and 1050–1150?C, underconditions of controlled hydrogen fugacity. The basalt end-memberwas Kilauea 1921 olivine tholeiite+3 wt.% H₂O, and the harzburgiteend-member was a mixture of olivine and orthopyroxene mineralseparates made from a mantle-derived lherzolite xenolith. Theexperiments on mixtures of basalt and harzburgite difl not reachequilibrium in runs ranging from 12 to 200 h duration. Relativelylarge concentration gradients persisted in both liquid and solidphases in mixed samples, whereas ‘control’ samplescontaining only basalt were reasonably homogeneous and wereprobably close to equilibrium. Compositions of solid phases produced, measured by electronmicroprobe, show a regular increase in Mg/(Mg+Fe) with increasingproportion of harzburgite at constant temperature, but olivineand clinopyroxene in mixed samples were not in Fe-Mg exchangeequilibrium. Modes measured for each sample show that the fractionof liquid relative to the amount of basalt in the sample wasconstant at constant temperature, and independent of bulk composition:reaction between 1921 basalt and harzburgite does not changethe mass of liquid in the system. Average experimental liquidcompositions for each sample were obtained by mass balance.Using Kds defined by the ‘control’ sample for eachtemperature, and mass balance constraints, phase assemblages(solid- and liquid-phase compositions and proportions) werecalculated for all mixtures. Whether samples included harzburgite or not, all average experimentalliquid compositions, and all predicted liquid compositions,for samples run at 1050?C, are high-alumina basalts by the definitionof Kuno (1960). By the criteria of Irvine & Baragar (1971),all but two average experimental liquid compositions in basalt-harzburgitemixtures, and all predicted liquid compositions in basalt-harzburgitemixtures, are calc-alkaline basalts and basaltic andesites,whereas liquids in samples containing only basalt are tholeiiticbasalts. Combined crystallization and reaction with harzburgitein the upper mantle will produce calc-alkaline derivative liquidsfrom an olivine tholeiite liquid under conditions of temperature,pressure, water and oxygen fugacity, and initial bulk compositionwhich would produce a tholeiitic liquid line of descent by crystallizationin a closed system. ^*Present address: Woods Hole Oceanographic Institution, Woods Hole, Massachusetts 02543Present address: Grant Institute of Geology, University of Edinburgh, West Mains Road, Edinburgh EH9 3JW, UK     

The U.K. Regional Research Laboratory Initiative 1987–1991

Abstract

The Economic and Social Research Council in the United Kingdom (U.K.) established the Regional Research Laboratory (RRL) Initiative in 1987 to improve facilities for data processing in the social sciences. The Trial Phase in 1987, which was modestly funded for 18 months, established four trial sites and a National Co-ordinator. The Main Phase of the Initiative, covering 8 laboratories at 10 locations, was launched in October 1988, following submission and selection of proposals. Although not originally planned as such, the initiative became a Geographical Information Systems (GIS) programme because the best proposals came from geographers and planners skilled in the processing of spatial data and because of interest stimulated by the influential Chorley Report. This article reviews the major aims of the Initiative and the progress reached after two years to September 1990. The initiative was highly effective in stimulating new research and development work that had regional, national and international dimensions. Nevertheless, with the exception of one RLL, funding has not been continued beyond 1991 and the initiative has been replaced by a network of University Departments working to continue the academic work with GIS in the U.K. for the next three years.     

Chronology of deglaciation based on 10Be dates of glacial erosional features in the Grimsel Pass region, central Swiss Alps

Surface exposure dating, using in situ produced cosmogenic ¹⁰Be, is applied to determine the time since deglaciation of bedrock surfaces in the Grimsel Pass region. Nine ¹⁰Be dates from bedrock surfaces corrected for cover by snow are minimum ages for deglaciation of the pass. Four ¹⁰Be dates from surfaces below 2500 meters above sea level (m a.s.l.) on Nägelisgrätli, east of Grimsel Pass, yield ages that range from about 14 000 to 11 300 years. Three ¹⁰Be dates from locations above 2600 m a.s.l. on Nägelisgrätli are between about 11 700 and 10 400 years. Two ¹⁰Be dates from locations at 2560 m a.s.l. below Juchlistock are about 12 100 and 11 000 years. The geographical distribution of ¹⁰Be dates on Nägelisgrätli either may show the timing of progressive deglaciation of Grimsel Pass or may reflect differences in subglacial erosion of bedrock in the pass region. All dates are discussed in the context of deglaciation of the late Würmian Alpine ice cap and deglaciation from Last Glacial Maximum (LGM) ice extents in other regions.     

Cosmic-ray exposure ages of diogenites and the recent collisional history of the howardite,eucrite and diogenite parent body/bodies

Abstract— We determined the cosmic-ray exposure age of 20 diogenites from measured cosmogenic noble gas isotopes and calculated production rates of ³He, ²¹Ne and ³⁸Ar. The production rates were calculated on the basis of the measured chemical composition and the cosmogenic ²²Ne/²¹Ne ratio of each sample. The shielding conditions of each sample were also checked on the basis of the measured ¹⁰Be and ²⁶AI concentrations. The exposure ages range from 6 to 50 Ma but do not form a continuous distribution: ten ages cluster at 21–25 Ma and four at 35–42 Ma. The two diogenite clusters coincide with the 22 Ma and 38 Ma peaks in the exposure age distribution of eucrites and howardites. After the selection from literature data of 32 eucrites and 11 howardites with reliable ages, we find a total of 23 howardite, eucrite and diogenite (HED) group meteorites at 20–25 Ma and 10 at 35–42 Ma. The shape of the two peaks is consistent with single impact events, and random number statistics show that they are statistically significant at the 99% level. Altogether, this provides strong evidence for two major impact events 22 Ma and 39 Ma ago. Although these two events can explain more than half of all HED exposure ages, it takes at least five impact events to explain all ages <50 Ma. An impact frequency of one per 10 Ma corresponds to projectiles of at least 2–4 km in diameter for Vesta and of 60–300 m for the 100× smaller Vesta-derived “vestoids.” Based on the HED exposure-age distribution, the size distribution of the main-belt asteroids and the difference in size between Vesta and the kilometer size vestoids, we favor Vesta as the major source of HED meteorites, although some of the meteorites may have been ejected from the vestoids rather than directly from Vesta.