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This paper explores the inherent contradiction and conceptual conflict that arises when sacred sites are marketed as secular for the purpose of promoting tourism. The question of conflict is further frustrated within the context of Israel’s contested religious landscape and Israeli policy. Using a Lefebvrian framework, the historical development of the Bahai Gardens in Haifa, Israel, the tourism board’s promotion of the site as Haifa’s primary tourist designation, and the distinct spatial practices that have been used by both constituencies are investigated. Further, the authors posit that the Bahai Gardens are multi-dimensional spaces characterized by two different socio-spatial processes and practices that co-exist—the tourist’s and the pilgrim’s. These practices transform the holy site into a secular shared community asset. The paper concludes with a discussion of the socio-spatial implications of the case and its broader implications concerning the globalization of tourism and the efficacy of developing “layered” Lefebvrian triad to try and avoid conflict.  相似文献   

4.
Becky Mansfield 《Geoforum》2004,35(3):313-326
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5.
The mineralogy and chemistry of gold-bearing listwaenites of Gemiköy in the Araç massif (southern part of the Daday-Devrekâni massif) were investigated in detail. The process of listwaenitization and the reasons for gold enrichment in the area are discussed. The listwaenites have no direct contact with any magmatic intrusion or extrusion. Detailed chemical analysis showed that the listwaenitized rocks contain silica-, silica and carbonate-, and carbonate-rich parts. Each part is different chemically from the others, even in terms of accessory mineral content. In general, the listwaenites differed chemically and mineralogically from the surrounding ultramafic rocks. In particular, SiO2 and CaO contents of listwaenites were higher and MgO and Al2O3 contents were lower than in the surrounding ultramafic rocks. Furthermore, Ni, As, Mn, Zn, Pb and Co enrichment occurred during listwaenitization, while K was absent and Ni enrichment was detected especially in silica and carbonate-, and carbonate-rich parts. Finally, Gemiköy listwaenites are interpreted as autometamorphic, even though they show similarities to allometamorphic listwaenites according to Ploshko's (1963) classification.  相似文献   

6.
The Al–Mg-rich granulites from the In Ouzzal craton, Algeria, show a great diversity of mineral reactions which correspond to continuous equilibria as predicted by phase relationships in the FeO–MgO–Al2O3–SiO2 system. The sequence of mineral reactions can be subdivided into three distinct stages: (1) a high-P stage characterized by the growth of coarse mineral assemblages involving sapphirine and the disappearance of early corundum and spinel-bearing assemblages; (2) a high-T stage characterized by the development of Sa–Qz-bearing assemblages; and (3) a later stage, in which garnet-bearing assemblages are replaced by more or less fine symplectites involving cordierite. During the course of early mineral reactions, the distribution coefficient, Kd, between the various ferromagnesian phases decreased significantly whereas Al2O3 in pyroxene increased concomitantly. These observations, when combined with topological constraints, clearly indicate that the high-P stage 1 was accompanied by a significant rise in temperature (estimated at 150 ± 50° C) under near isobaric conditions, in agreement with the reaction textures. By stage 2, pressure and temperature were extreme as evidenced by the low Kd value between orthopyroxene and garnet (Kd= 2.06–1.99), the high alumina content in pyroxene (up to 11.8%) and the high magnesium content in garnet [100 Mg/(Mg + Fe) = 60.6]. Mineral thermometry based on Fe–Mg exchange between garnet and pyroxene and on Al-solubility in pyroxene gives temperatures close to 970 ± 70° C at 10 ± 1.5 kbar. These results are in agreement with the development of Sa–Qz assemblages on a local scale. Late mineral reactions have been produced during a decompression stage from about 9 to 6 kbar. Except for local re-equilibration of Mg and Fe at grain boundaries, there is no evidence for further reactions below 700° C. We interpreted the whole set of mineral reactions as due to changes in pressure and temperature during a tectonic episode located at c. 2 Ga. Because of the lack of evidence for further uplift after the thermal relaxation which occurred at c. 6 kbar, it is possible however that the exhumation of this granulitic terrane occurred in a later tectonic event unrelated to its formation.  相似文献   

7.
Morphological and vegetation mapping and stratigraphic studies were carried out on a 60 by 250 m low–centered polygon field on a flood–plain of the Riviére Deception in the continuous permafrost zone of northernmost Ungava. Analyses of grain size, water and ice content, deformation structures, and macrorests were carried out on drill–core samples, up to a maximum depth of 3.19 m, and radiocarbon dates were obtained from several peat horizons. Five different vegetational habits were identified: uplifted banks, ice–wedge fissures, hummocky centres, wet polygon centres, and water ponds. The stratigraphic analyses revealed many sand layers and organic layers, alternating with a few layers of segregated ice. In the raises banks, brown fen peats represent former wet conditions prior to bank uplift. Total ice volumes of the core samples from polygon centres and banks averaged 60%, and were generally in the form of pore ice. Segregated ice was concentrated in ice wedges. The Low gradient of the polygon field and the shallow active layer are responsible for impded drainage. The origins of this isolated low–centred polygon field are discussed in terms of special local terrain conditions. River flooding since glacio–isostatic emergence at 6000 BP repeatedly spread alluvial sands onto the low flood–plain, which thus became progressively built up to its present elevation. Peat layers buried by these alluvial sands have permitted the changing local drainage conditions to be radiocarbon–dated for the last 2600 years for the core sites. Impeded drainage, low winter temperatures, probable thin snow cover, rapid sedimentation of flood–plain sands, and high volumetric ice contents have created the critical thermal regime necessary for repeated frost cracking in a polygonal pattern, with concomitant ice–wedge dev–elopment. Ice wedges developed at least as early as 2200 BP, causing the formation of low banks. Further growth of ice wedges deformed the peat and sand layers on the bank margins and led to the rise of the latter to heights of 0.5 to 1 m above the intervening low wet polygon centres. More water was then collected in the depressions, leading to a transformations of the vegetation cover from mossy heath to sphagnum bog, wet fen, sedge-covered ponds, and eventually in some cases to open-water pools. The stratigraphic evidence suggests that several generations of high banks formed and disappeared and that their position has changed. Deformation by continued ice–wedge growth has been insignificant since 1000 BP, However. A relatively thick surface peat layer also indicates that sand layers have not been contributed to the polygon field by flooding since ? 500 BP.  相似文献   

8.
The Late Carboniferous–Early Permian Itararé Group is a thick glacial unit of the Paraná Basin. Five unconformity-bounded sequences have been defined in the eastern outcrop belt and recognized in well logs along 400 km across the central portion of the basin. Deglaciation sequences are present in the whole succession and represent the bulk of the stratigraphic record. The fining-upward vertical facies succession is characteristic of a retrogradational stacking pattern and corresponds to the stratigraphic record of major ice-retreat phases. Laterally discontinuous subglacial tillites and boulder beds occur at the base of the sequences. When these subglacial facies are absent, deglaciation sequences lie directly on the basal disconformities. Commonly present in the lowermost portions of the deglaciation sequences, polymictic conglomerates and cross-bedded sandstones are generated in subaqueous proximal outwash fans in front of retreating glaciers. The overlying assemblage of diamictites, parallel-bedded and rippled sandstones, and Bouma-like facies sequences are interpreted as deposits of distal outwash fan lobes. The tops of the deglaciation sequences are positioned in clay-rich marine horizons that show little (fine-laminated facies with dropstones) or no evidence of glacial influence on the deposition and likely represent periods of maximum ice retreat.  相似文献   

9.
Metapelites, migmatites and granites from the c. 2 Ga Mahalapye Complex have been studied for determining the P–T–fluid influence on mineral assemblages and local equilibrium compositions in the rocks from the extreme southwestern part of the Central Zone of the Limpopo high‐grade terrane in Botswana. It was found that fluid infiltration played a leading role in the formation of the rocks. This conclusion is based on both well‐developed textures inferred to record metasomatic reactions, such as Bt ? And + Qtz + (K2O) and Bt ± Qtz ? Sil + Kfs + Ms ± Pl, and zonation of Ms | Bt + Qtz | And + Qtz and Grt | Crd | Pl | Kfs + Qtz reflecting a perfect mobility (Korzhinskii terminology) of some chemical components. The conclusion is also supported by the results of a fluid inclusion study. CO2 and H2O ( = 0.6) are the major components of the fluid. The fluid has been trapped synchronously along the retrograde P–T path. The P–T path was derived using mineral thermobarometry and a combination of mineral thermometry and fluid inclusion density data. The Mahalapye Complex experienced low‐pressure granulite facies metamorphism with a retrograde evolution from 770 °C and 5.5 kbar to 560 °C and 2 kbar, presumably at c. 2 Ga.  相似文献   

10.
Mafic volcanic rocks of the Fortescue Group form the lowermost stratigraphic unit of the 100,000 km2 Hamersley Basin on the southern margin of the Archean Pilbara Craton, Western Australia. A regional burial metamorphic gradient extends across the basin from prehnite–pumpellyite facies in the north to greenschist facies in the south. Phase equilibria modelling of mafic rocks with the computer program thermocalc , in subsets of the system Na2O–CaO–K2O–FeO–MgO–Al2O3–SiO2–H2O–Fe2O3, successfully reproduces observed metamorphic mineral assemblages, giving conditions of ~210 °C, 2 kbar in the north and 335 °C, 3.2 kbar in the south. Superimposed on this metamorphic gradient, regional‐scale metasomatism in the Fortescue Group progressively produces a suite of prehnite‐bearing and pumpellyite–quartz/epidote–quartz‐dominated assemblages. Further modelling of variably metasomatized samples consistently estimates conditions of 260–280 °C, 2.5–3 kbar across the basin. All modelled samples were likely metasomatized at approximately the same structural level, following regional deformation during the Ophthalmian orogeny. Folding during the Ophthalmian orogeny produced topographic and/or tectonic driving forces for regional‐scale fluid flow, pushing metasomatic fluid northwards across the Hamersley Basin. These new phase equilibria calculations support previous interpretations linking the Ophthalmian orogeny, fluid flow and upgrading of Hamersley iron ore deposits. We propose an extension of this fluid flow to the Fortescue Group, the metasomatism of which may have contributed a source of Fe to the Hamersley iron ore deposits.  相似文献   

11.
The Western Depression of the Liaohe Basin is the major exploration area of the Liaohe Oilfield, and its main source rocks consist of the third and fourth members of the Shahejie Formation (Es3 and Es4). These source rocks are widely distributed in the depression, with semi-deep lake and fan delta as the main sedimentary facies, brown oil shale and black gray-dark gray mudstone as the main rocks, and a total thickness of 270-1450 m. The kerogens are mainly of the types I and IIA, and partly of the type IIB and least of the type III. The Ro values range from 0.4%-0.8%, indicating an evolution stage from immature to mature. The maturity of Es4 source rocks is rela-tively high, reaching the early mature stage, but their distribution and thickness are lower than those of Es3. Besides, according to biomarker analysis, it is thought that the source rocks of Es3 and Es4 are characterized by mixed input, and most of the source rocks were formed in the brackish water-saline and strongly oxygen-free environment. Fur-thermore, the Qingshui, Niuxintuo and Chenjia sags are believed to possess greater potential for hydrocarbon gen-eration and expulsion, for they are source rocks with a larger thickness, have higher organic carbon contents, belong to better organic matter types and possess higher maturities.  相似文献   

12.
The present study aims to interpret the occupation of terra firme (nonflooded uplands) archeological sites located at Tapirapé‐Aquiri National Forest in the Brazilian state of Pará, through an integrated analysis of pedological, archeological, and geochemical data. We focus on seven archaeological sites, selected among 22 identified in the region. Radiocarbon and thermoluminescence dating indicate distinct periods of occupation over the past ∼6000 years, and the pedo‐geochemical data identify intra‐ and inter‐site differences in soil. Archaeological, chronometric, and pedo‐geochemical data provide a basis for the functional classification of archeological sites found in the region and help to identify specific human activity areas. The results lead us to infer that many of the archeological sites were the result of multiple occupations that left a persistent pedological signature on the landscape.  相似文献   

13.
A population of the invasive musselMusculista senhousia was monitored bimonthly from May 1999 through April 2000 in the Sacca di Goro, a brackish lagoon of the Po River Delta, Northern Adriatic Sea, in order to give information on the gametogenic cycle, population dynamics, and secondary production of this successful invader. The gonad underwent 4 different stages: spent (December to February), developing (March to May), ripe (June to August), and spawning (September to November). The population was numerically dominated by a single cohort of individuals for most of the year. The mean size of this cohort rapidly increased to 24–25 mm shell length, after which growth slowed and mussels rarely grew larger than 30–32 mm. Summer anoxia may have greatly reduced mussel abundance; annual cohort mortality was 95%. No recruitment was registered on the bed until February 2000, and there was a large pulse of new recruits in April when two cohorts were clearly recognizable. The established bed was the primary site for new recruitment. Secondary production, calculated with two different methods, gave comparable estimates; P:B ratios were 1.5 and 1.7.M. senhousia beds seemed to facilitate the presence of other macrofaunal taxa: abundance of some species (a small gastropod, amphipods, and tube-building polychaetes) were significantly higher within mussel mats at two sites sampled in May 2000 than they were in soft-sediments ∼100 m away.  相似文献   

14.
Based on previous studies and detailed field investigations of the Dexing porphyry copper deposit, the Yinshan Ag-Pb-Zn deposit and the Jinshan shear zone – hosted gold deposit in the Dele Jurassic volcanic basin, in the northeastern Jiangxi province, East China, we propose that the three deposits share spatial, temporal and genetic relationships and belong to the same metallogenic system. Dexing is a typical porphyry Cu–Au–Mo deposit in which both ore-forming fluid and metals are derived from the granite porphyry. The Yinshan deposit consists of a porphyry copper ore located in the cupola of a quartz porphyry stock, in the lower part, and Ag–Pb–Zn ore veins in the upper part. The hydrothermal fluids were mainly derived from the magma in the early stages of the mineralizing event and became mixed with meteoric waters in the late stages. Its ore metals are magma-derived. Both the Jinshan base metal veins and the Hamashi, Dongjie and Naikeng quartz vein-type gold deposit are hosted by brittle–ductile structures, which are distal in relation to the porphyry intrusions and were formed by mixed magmatic fluids and meteoric water, whereas the gold was mainly leached from the country rocks (Mesoproterozoic Shuangqiaoshan Group phyllite and schist). The deposits show a distinct spatial arrangement from porphyry Cu, to epithermal Ag–Pb–Zn and distal Au. We suggest a porphyry–epithermal–distal vein ore system model for this group of genetically related mineral deposits. They were formed in a back-arc setting in a Middle Jurassic active continental margin, with magmas derived from the subducted slab.  相似文献   

15.
The determination of the thermal (temperature–time) histories of high‐P metamorphic terranes has been commonly based on the concepts of slow cooling and closure temperatures. In this paper, we find that this approach cannot reconcile a geochronological data set obtained from the amphibolite‐facies allochthonous Leknes Group of the Lofoten islands, Norway, which reveals an extremely complex thermal history. Using detailed results from several different geochronometers such as 40Ar/39Ar, Rb–Sr and U–Pb, we show that a model invoking multiple, short‐lived thermal pulses related to hot‐fluid infiltration channelized by shear zones can reconcile this complicated data set. This model suggests that hot fluids infiltrated throughout basement shear zones and affected the overlying cold allochthon, partially resetting U/Pb rutile and titanite ages, crystallizing new zircon and produced identical 40Ar/39Ar and Rb/Sr ages in muscovite, biotite and amphibole in various rocks throughout the region. This paper shows the enormous potential of coupling laser Ar‐spot data with thermal modelling to identify and constrain the duration of short‐lived events. An optimal P–T–t history has been derived by modelling the age data from a previously dated large muscovite crystal (Hames & Andresen, 1996, Geology, 24 :1005) and using Zr‐in‐rutile thermometry which is consistent with all geochronological data and geological constraints from the basement zones and allochthon cover. This tectonothermal model history suggests that there have been three episodic hot‐fluid and 40Ar‐free infiltration events, resulting in the total resetting of Ar ages during the Scandian (425 Ma) for 1 Ma at 650°C and two reheating events at 415 Ma for 400 ka at 650°C and at 365 Ma for 50 ka at 600°C, which are modelled as thermal spikes above an ambient temperature of 300°C. Independent confirmation of these parameters was provided by Pb‐diffusion modelling in rutile and titanite. The model suggests that the amphibolite facies rocks of the Leknes Group probably remained cold before being exhumed for at least 60 Ma (425–365 Ma) and successfully explains the presence of different minerals that crystallized or were totally/partially reset in the allochthon and in the basement. The migration of hot fluids for short periods of times within conduits extending through the basement and allochthon rock units is likely associated with episodic seismic activity during the Caledonian orogeny.  相似文献   

16.
The Saumane‐Venasque compound palaeovalley succession accumulated in a strongly tide‐influenced embayment or estuary. Warm‐temperate normal marine to brackish conditions led to deposition of extensive cross‐bedded biofragmental calcarenites. Echinoids, bryozoans, coralline algae, barnacles and benthic foraminifera were produced in seagrass meadows, on rocky substrates colonized by macroalgae and within subaqueous dune fields. There are two sequences, S1 and S2, the first of which contains three high‐frequency sequences (S1a, S1b and S1c). Sequence 1 is largely confined to the palaeovalley with its upper part covering interfluves. Each of these has a similar upward succession of deposits that includes: (i) a basal erosional surface that is bored and glauconitized; (ii) a discontinuous lagoonal lime mudstone or wackestone; (iii) a thin conglomerate generated by tidal ravinement; (iv) a transgressive systems tract series of cross‐bedded calcarenites; (v) a maximum flooding interval of argillaceous, muddy quartzose, open‐marine limestones; and (vi) a thin highstand systems tract of fine‐grained calcarenite. Tidal currents during stages S1a, S1b and S1c were accentuated by the constricted valley topography, whereas basin‐scale factors enhanced tidal currents during the deposition of S2. The upper part of the succession in all but S1c has been removed by later erosion. There is an overall upward temporal change with quartz, barnacles, encrusting corallines and epifaunal echinoids decreasing but bryozoans, articulated corallines and infaunal echinoids increasing. This trend is interpreted to be the result of changing oceanographic conditions as the valley was filled, bathymetric relief was reduced, rocky substrates were replaced as carbonate factories by seagrass meadows and subaqueous dunes, and the setting became progressively less confined and more open marine. These limestones are characteristic of a suite of similar cool‐water calcareous sand bodies in environments with little siliciclastic or fresh water input during times of high‐amplitude sea‐level change wherein complex inboard antecedent topography was flooded by a rising ocean.  相似文献   

17.
The southern Jiangxi Province is a major part of the Nanling W–Sn metallogenic province of southern China, where all W–Sn ore deposits are temporally and spatially related to Mesozoic granitic intrusions. The Tianmenshan–Hongtaoling orefield is a recently explored territory endowed by several styles of W–Sn mineralization. The orefield comprises three composite granitic plutons: Tianmenshan, Hongtaoling and Zhangtiantang associated with several tens of W–Sn-polymetallic ore deposits (Maoping, Baxiannao, Niuling, Zhangdou, Yaolanzhai and others) along their contacts. In this study, four new SHRIMP zircon U–Pb ages were determined for three composite granitic plutons, and 33 molybdenite samples from five W–Sn deposits were analysed by ICP-MS Re–Os isotopic method. SHRIMP zircon U–Pb ages for both medium to coarse-gained biotite granite and porphyritic biotite monzogranite from the Tianmenshan composite pluton are 157.2 ± 2.2 Ma and 151.8 ± 2.9 Ma, respectively. Molybdenite Re–Os isochron ages for the related Baxiannao fracture-controlled tungsten deposits are 157.9 ± 1.5 Ma. Maoping greisens-type tungsten deposits were emplaced at 155.3 ± 2.8 Ma and the Maoping wolframite–quartz veins at 150.2 ± 2.8 Ma, respectively. The SHRIMP U–Pb age of zircons from the Hongtaoling biotite granite is 151.4 ± 3.1 Ma whereas the molybdenite Re–Os isochron ages of the genetically related Niuling endocontact tungsten quartz veins and Zhangdou exocontact tungsten quartz veins are 154.9 ± 4.1 to 154.6 ± 9.7 Ma and 149.1 ± 7.1 Ma, respectively. The SHRIMP zircon U–Pb age of the Zhangtiantang fine-grained muscovite granite is 156.9 ± 1.7 Ma, whereas the molybdenite Re–Os isochron age for the related Yaolanzhai greisens-type tungsten deposit is 155.8 ± 2.8 Ma. These new age data, combined with those available from the literature, indicate that the ages of W–Sn ores and related granites are Late Jurassic with a peak at 150 to 160 Ma, which corresponds to the widespread Mesozoic metallogenic event in southern China. Molybdenites from this group of tungsten deposits have quite low Re contents (29.1 to 2608 ppb), suggesting continental crustal provenance of the ore metals.  相似文献   

18.
In situ LA–ICP–MS U–Pb monazite geochronology from the Boothby Hills in the Aileron Province, central Australia, indicates that the region records more than 80 Ma of high‐T, low‐P (HTLP) anatectic conditions during the Early Mesoproterozoic. Monazite ages from granulite facies rocks and leucosomes span the interval 1576–1542 Ma. Pegmatites that overprint the regional gneissic fabric and are interpreted to record the last vestiges of melt crystallization give ages between 1523 and 1513 Ma. Calculated P–T pseudosections suggest peak metamorphic conditions in excess of 850 °C at 0.65–0.75 GPa. The retrograde evolution was characterized by a P–T path that involved minor decompression and then cooling, culminating with the development of andalusite. Integration of the geochronological data set with the inferred P–T path trajectory suggests that suprasolidus cooling must have been slow, in the order of 2.5–4 °C Ma?1. In addition, the retrograde P–T path trajectory suggests that HTLP conditions were generated within crust of relatively normal thickness. Despite the long duration over which anatectic conditions occurred, there is no evidence for external magmatic inputs or evidence that HTLP conditions were associated with long‐lived extension. Instead, it seems probable that the long‐lived HTLP metamorphism was driven to a significant extent by long‐lived conductive heating provided by high crustal heat production in voluminous pre‐metamorphic granitic rocks.  相似文献   

19.
Abstract: The Anle Sn‐Cu and Huanggangliang Fe‐Sn deposits have been exploited in the Linxi district, which is located 165 km northwest of Chifeng City in northern China. In this study the formation mechanisms of the tin deposits in the Anle and Huanggangliang mining area were investigated to understand the mechanisms of tin mineralization in northern China. The veins of the Anle deposit are divided into cassiterite–quartz–chlorite veins, chalcopyrite‐bearing quartz veins, cassi–terite–chalcopyrite–bearing quartz veins and sphalerite‐quartz veins. The sequence of mineralization is tin mineralization (stage I), copper mineralization (stage II), and lead‐zinc mineralization (stage III). The Huanggangliang tin deposit consists of magnetite skarn orebodies and many cassiterite‐bearing feldspar–fluorite veins and veinlets cutting the magnetite orebodies. The fluid inclusions in quartz and fluorite in ores from the Anle and Huanggangliang tin deposits are divided into two‐phase fluid inclusions, vapor‐rich fluid inclusions and poly‐phase fluid inclusions. The final homogenization temperatures of fluid inclusions of quartz in the ores of the Anle deposit and fluorite of tin‐bearing feldspar veins in the Huanggangliang tin deposit range from 195 to 425C and from 215 to 450C, respectively. The fluids responsible for the Anle and Huanggangliang tin deposits were of very high temperature and NaCl‐rich ones containing K, Ca, Al, Si, Ti, Fe and Cl in addition to ore metals such as Sn and Cu. The temperature and chemical composition of fluid in fluid inclusions of igneous rocks in the mining area are very similar to those of fluid in fluid inclusions in the ores of these deposits. The fluid for these ore deposits had a close relation with the fluid coexisting with melt of Late Jurassic granitic rocks in this mining area. Salinities of fluid inclusions from these ore deposits and granitic rocks in the mining area were estimated to range from 35 to 50 wt % NaCl equivalent. Based on arsenopy‐rite geothermometry and fluid inclusion studies, a fluid containing 40 wt% NaCl (eq.) could be formed by phase separation of fluid having 6 wt% NaCl (eq.) at a temperature of 420 to 500C and a pressure of 0.3 to 0.4 kb. The temperatures and pressures presented above indicate an NaCl‐rich magmatic fluid derived from granitic melt that had intruded into a shallow level of crust caused the Sn–Fe–Cu mineralization of the mining area. The geological relationship between these ore deposits and granitic bodies around the ore deposits, and the similarity of fluids forming these ore deposits and coexisting with granitic melt, suggest that these ore deposits were formed by the activity of fluid derived from granitic melt in Late Jurassic age.  相似文献   

20.
Sediments from two small lakes distal to the Tromsø–Lyngen moraine at Tromsø, northern Norway, indicate that the area was deglaciated prior to c. 11.7 14C ka BP. The earliest vegetation was dominated by calciphilous and heliophilous pioneer plants on unstable soils; this changed to a vegetation reflecting a dry continental climate until c. 10.7 14Cka BP. A phase (10.7–10.5 14Cka BP) with snow-bed communities was followed by one with a mosaic of plant communities. This was succeeded by Empetrum heaths c. 10.3 14Cka BP, then by an open forest with Betula pubescens after 10.0 14Cka BP. Ice-front oscillations in the Tromsø area are evaluated. The main part of the Younger Dryas glacial readvance, the Tromsø–Lyngen event, probably occurred between 10.7 and 10.3 14Cka BP.  相似文献   

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