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MARIA ELISA CHRISTIE 《Geographical review》2004,94(3):368-390
ABSTRACT. The house‐lot garden in central Mexico is gendered space where changing cultural identities are negotiated, re‐created, and celebrated as “tradition” is continually redefined. No clear boundary separates the kitchen from the house‐lot garden or the private space of the household from the semipublic space of the community. During collective food preparation for religious fiestas, gendered reciprocity networks strengthen community relations and foster alliances between traditional neighborhoods and between communities in the region. At the intersection of everyday life and fiestas, food‐preparation spaces, or kitchenspaces, in the house‐lot garden are fertile areas in which to explore the cultural reproduction of nature‐society relations. They are vital to understanding gender, place, and culture in this region and represent people's symbolic connection with the land in increasingly urban contexts. This article analyzes the sense of place that Mexican women derive from their house‐lot gardens. 相似文献
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EILIV LARSEN KURT H. KJæR MARIA JENSEN IGOR N. DEMIDOV LENA HAKANSSON AAGE PAUS 《Boreas: An International Journal of Quaternary Research》2006,35(3):476-492
A section, almost 20 km long and up to 80 m high, through alternating layers of diamict and sorted sediments is superbly exposed on the north coast of the Kanin Peninsula, northwestern Russia. The diamicts represent multiple glacial advances by the Barents Sea and the Kara Sea ice sheets during the Weichselian. The diamicts and stratigraphically older lacustrine, fluvial and shallow marine sediments have been thrust as nappes by the Barents Sea and Kara Sea ice sheets. Based on stratigraphic position, OSL dating, sea level information and pollen, it is evident that the sorted sediments were deposited in the Late Eemian-Early Weichselian. Sedimentation started in lake basins and continued in shallow marine embayments when the lakes opened to the sea. The observed transition from lacustrine to shallow marine sedimentation could represent coastal retreat during stable or rising sea level. 相似文献
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The sandy deposits produced by tsunamis and liquefaction share many sedimentary features, and distinctions between the two are important in seismically active coastal zones. Both types of deposits are present in the wetlands bordering Puget Sound, where one or more earthquakes about 1100 years ago caused both tsunami flooding and sediment venting. This co‐occurrence allows an examination of the resulting deposits and a comparison with tsunami and liquefaction features of modern events. Vented sediments occur at four of five wetland field localities and tsunami deposits at two. In comparison with tsunami deposits, vented sediments in this study and from other studies tend to be thicker (although they can be thin). Vented sediments also have more variable thickness at both outcrop and map scale, are associated with injected dykes and contain clasts derived from underlying deposits. Further, vented sediments tend to contain a greater variety of sedimentary structures, and these structures vary laterally over metres. Tsunami deposits compared with vented sediments are commonly thinner, fine and thin landward more consistently, have more uniform thickness on outcrop and map scales, and have the potential of containing coarser clasts, up to boulders. For both tsunami deposits and vented sediments, the availability and grain size of source material condition the characteristics of the deposit. In the cases presented in this paper, both foraminifera and diatom assemblages within tsunami deposits and vented sediments consisted of brackish and marine species, and no distinction between processes could be made based on microfossils. In summary, this study indicates a need for more careful analysis and mapping of coastal sediments associated with earthquakes to avoid misidentification of processes and misevaluation of hazards. 相似文献
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MARIA MIMIKOU 《水文科学杂志》2013,58(3):369-383
ABSTRACT The suspended sediment rating curves for six stations on four rivers in western and northern Greece are investigated. For each station the suspended sediment load is a power function of the water discharge, which may be distinguished according to wet and dry seasons; the latter yields higher sediment loads for a given discharge than the former. This is due to the higher erosivity of dry season rainfall compared to wet season rainfall producing the same runoff. All rating curve exponents b lie in the range 2.5–3.5 for the wet and 2.0–3.0 for the dry season and are related to the constants a of the curves by empirical equations. The variation in a and b is explained in terms of the annual precipitation and area of the basin, the hypsometric fall, the main channel length, and the average bedslope of the river from the basin divide to the station, through empirical relationships, which also permit the prediction of rating curves for ungauged basins. 相似文献
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Climate and landscape during Heinrich Event 3 in south‐western Europe: the small‐vertebrate association from Galls Carboners cave (Mont‐ral,Tarragona, north‐eastern Iberia) 
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EMILIANO MUTTI DANIEL BERNOULLI FRANCO RICCI LUCCHI ROBERTO TINTERRI 《Sedimentology》2010,57(3):933-934
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Geochronology and Petrogenesis of the Cretaceous Antampombato-Ambatovy Complex and Associated Dyke Swarm, Madagascar 总被引：1，自引：0，他引：1
MELLUSO LEONE; MORRA VINCENZO; BROTZU PIETRO; TOMMASINI SIMONE; RENNA MARIA ROSARIA; DUNCAN ROBERT A.; FRANCIOSI LUIGI; D'AMELIO FOSCO 《Journal of Petrology》2005,46(10):1963-1996
The Antampombato–Ambatovy complex is the largest intrusionin the central–eastern part of the Cretaceous flood basaltprovince of Madagascar, with an exposed surface area of about80 km2. It has an 40Ar/39Ar incremental heating age of 89·9± 0·4 Ma and a U–Pb age of 90 ± 2Ma. The outcropping plutonic rocks range from dunite and wehrlite,through clinopyroxenite and gabbro, to sodic syenite. A dykeswarm cross-cutting some of the above lithologies (and the nearbyPrecambrian basement rocks) is formed of picritic basalts, alkalito transitional basalts, benmoreites and rhyolites; some ofthe latter are peralkaline. A few basaltic dykes have cumulateolivine textures, with up to 26 wt % MgO and 1200 ppm Ni, whereasothers have characteristics more akin to those of primitiveliquids (9 wt % MgO; Mg-number 0·61; 500 ppm Cr; 200ppm Ni). These basalts have relatively high TiO2 (2·2wt %) and total iron (14 wt % as Fe2O3), and moderate contentsof Nb (10–11 ppm) and Zr (c. 100 ppm). Initial (at 90Ma) Sr- and Nd-isotope ratios of the clinopyroxenites and basaltdykes are 0·7030–0·7037 and 0·51290–0·51283,respectively. Syenites and peralkaline rhyolites have Sr- andNd-isotope ratios of 0·7037–0·7039 and 0·51271–0·51274,respectively. The data suggest derivation of the parental magmasfrom a time-integrated depleted mantle source, combined withsmall amounts of crustal contamination in the petrogenesis ofthe more evolved magmas. The isotopic compositions of the mafic–ultramaficrocks are most similar to those of the mid-ocean ridge basalt(MORB)-like igneous rocks of eastern Madagascar, and suggestthe existence of an isotopically ‘depleted’ componentin the source of the entire Madagascar province, even thoughthe Antampombato basalts are chemically unlike the lavas anddykes with the same depleted isotopic signature found in westernMadagascar. If this depleted component is plume-related, thissuggests that the plume has a broadly MORB-source mantle composition.The existence of isotopically more enriched magma types in theMadagascan province has several possible petrogenetic explanations,one of which could be the interaction of plume-related meltswith the deep lithospheric mantle beneath the island. KEY WORDS: geochronology; flood basalts; Antampombato–Ambatovy intrusion; Cretaceous; Madagascar 相似文献