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991.
L. M. Frink 《International Journal of Historical Archaeology》2009,13(3):282-302
Novel technologies linked to women and men through identity-demarcated tasks and knowledge sets can potentially have differential
and even long-term effects on each group. This study follows the trajectory of two significant imports into the coastal western
Alaskan system, the firearm and the metal cook pot. These imports had different implications for coastal Yup’ik women and
men, young and old. Over time the gun became an integral piece of a man’s tool kit and one that had the potential to boost
production and thus a man’s access to status-building. However, these same tools had the potential to undermine the apprenticeship
system of male authority. Likewise, the metal cook pot replaced the productive oversight and skill set of elder women’s ceramic
production but created paths of independence for younger Yup’ik women. These changes in technology destabilized relative balances
of gender and age based status, security, and authority and fashioned new gender and age based social and economic opportunities
and limitations. 相似文献
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V. SÁNCHEZ E. VINDEL T. MARTÍN-CRESPO M. CORBELLA E. CARDELLACH D. BANKS 《Geofluids》2009,9(4):338-355
The fluorite deposits of Asturias (northern Iberian Peninsula) are hosted by rocks of Permo‐Triassic and Palaeozoic age. Fluid inclusions in ore and gangue minerals show homogenization temperatures from 80 to 170°C and the presence of two types of fluids: an H2O–NaCl low‐salinity fluid (<8 eq. wt% NaCl) and an H2O–NaCl–CaCl2 fluid (7–13 wt% NaCl and 11–14 wt% CaCl2). The low salinity and the Cl/Br and Na/Br ratios (Cl/Brmolar 100–700 and Na/Brmolar 20–700) are consistent with an evaporated sea water origin of this fluid. The other end‐member of the mixture was highly saline brine with high Cl/Br and Na/Br ratios (Cl/Brmolar 700–13 000 and Na/Brmolar 700–11 000) generated after dissolution of Triassic age evaporites. LA‐ICP‐MS analyses of fluid inclusions in fluorite reveal higher Zn, Pb and Ba contents in the high‐salinity fluids (160–500, 90–170, 320–480 p.p.m. respectively) than in the low‐salinity fluid (75–230, 25–150 and 100–300 p.p.m. respectively). The metal content of the fluids appears to decrease from E to W, from Berbes to La Collada and to Villabona. The source of F is probably related to leaching of volcanic rocks of Permian age. Brines circulated along faults into the Palaeozoic basement. Evaporated sea water was present in permeable rocks and faults along or above the unconformity between the Permo‐Triassic sediments and the Palaeozoic basement. Mineralization formed when the deep brines mixed with the surficial fluids in carbonates, breccias and fractures resulting in the formation of veins and stratabound bodies of fluorite, barite, calcite, dolomite and quartz and minor amounts of sulphides. Fluid movement and mineralization occurred between Late Triassic and Late Jurassic times, probably associated with rifting events related to the opening of the Atlantic Ocean. This model is also consistent with the geodynamic setting of other fluorite‐rich districts in Europe. 相似文献
994.
Petroleum-bearing fluid inclusions emit fluorescent light when excited with UV or visible light. The fluorescence decay time of the emission is dependent upon the wavelengths of the excitation and emission light, and the chemical composition of the petroleum oil. In general heavy oils have short lifetimes, whereas the emission from light oils is much longer lived. One can thus use plots of the fluorescence lifetime versus emission wavelength ( τ – λ plots), to show even subtle changes in the chemical composition of the entrapped oil. As a consequence, these τ – λ plots can be used for fluid inclusion research to discriminate different oil populations in situ . In particular, it is demonstrated that τ – λ plots discriminate two sets of inclusion oils in each of four North Atlantic basins [Jeanne d'Arc Basin (Newfoundland), Porcupine Basin (Ireland), Clair field West of Shetland (UK) and Kangerlussuaq Basin (East Greenland)] where multistage oil charge is inferred from other geological evidence. 相似文献
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Adrian R Bailey Catherine Brace David C Harvey 《Transactions (Institute of British Geographers : 1965)》2009,34(2):254-269
Despite the existence of research conducted by geographers eschewing or professing religious faith, the influence of researchers and their methods have yet to receive critical attention within the study of religion. The experience of three geographers working on a three-year research project suggests that it is vital to reflect upon the inter-subjective relationships and methodologies used to reconstruct the religious past. How do different subject positions influence our selections from historical records? We also consider whether the spatialities of putatively 'religious' archives, whether formally or informally constituted, make a difference to the construction of historiographical knowledge. In attempting to answer these questions, the paper argues that developing an awareness of different types of positionality, vis-à-vis religious faith and practice, combined with reflexivity, vis-à-vis methodology, can enrich the interpretative reconstruction of the religious past. 相似文献