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991.
992.
Jodi A. Barnes 《International Journal of Historical Archaeology》2011,15(4):669-706
Archaeology has the potential to contribute significant information about community building in the lives of former enslaved
laborers. In this article, I consider the role of race and racism in the creation, maintenance and material manifestation
of community in post-emancipation Appalachia. 相似文献
993.
Edward González-Tennant 《International Journal of Historical Archaeology》2011,15(3):509-532
This article calls for a specific form of comparative inquiry within historical archaeology as drawn from diaspora studies.
Such a project encourages archaeologists to compare research from emigrant areas alongside work at overseas sites. This diasporic
approach provides new potentials for engaging with the modern world by intersecting with both traditional and new aspects
of archaeological practice. In order to showcase these aspects of a diasporic approach, the author explores three case studies
from Montana, Peru, and New Zealand – connecting each to its related home area. The case studies explore how data drawn from
a group’s homeland can support established heritage practices, engage with modern social problems, and illuminate complexities
arising within sites based on ethnolinguistic differences within populations. 相似文献
994.
Włodzimierz Margielewski Piotr Kołaczek Adam Michczyński Andrzej Obidowicz Anna Pazdur 《Geochronometria》2011,38(2):138-154
The paper presents an analysis of depositional sequences of landslide peat bog situated in the depressions developed within
the landslide landforms Jesionowa in the Beskid Sądecki Mts. (Outer Carpathians). The peat bog, with depositional sequence
2.80 m long, started to form at the beginning of the Atlantic Phase ca. 6390–5910 cal BC. Palynological and lithological analyses
as well as several (14) radiocarbon age determinations of different horizons in the sediments enabled the reconstruction of
palaeoenvironmental changes during the Meso-and Neoholocene. The increase in climate humidity at the beginning of the Subboreal
and Subatlantic Phases was observed as delivery of minerogenic material to the peat bog basin and formation of a mineral horizon
and an illuvial level within the peat. The particularly intensive delivery of allochthonous material to the peat bog took
place at the beginning of the Subboreal Phase and was the result of both significant humid climate and increased human impact
(colonization of the Funnel Beaker Culture) in the landslide area. Similar influence of younger colonisations of landslide
area (Przeworsk Culture and, later, Valachian colonisation) was also recorded within the deposits of peat bog (illuvial and
mineral horizons) in the early Subatlantic Phase. Rejuvenation of the landslide zone and formation of the younger landslide
were connected with the increase in climate humidity at the beginning of the Subboreal Phase. The peat bog deposits situated
within this younger landslide, which are ca. 1.8 m thick, are significantly contaminated with mineral material. 相似文献
995.
Recent work has identified IR stimulated luminescence signals at elevated temperature from both potassium- and sodium-rich
feldspars that have much lower anomalous fading rates than the conventional signal measured using IR stimulation at 50°C.
This paper examines the stability of these signals for potassium-rich sedimentary feldspars. We show that the natural post-IR
IRSL (pIRIR) signal from a 3.6 Ma old sample is in apparent saturation on a laboratory generated dose response curve, i.e.
it does not show detectable fading in nature although a low fading rate is observed on laboratory time scales. We show that
the pIRIR signal has a greater thermal stability than the IRSL signal and that the trend in increasing thermal stability is
mirrored by a decreasing fading rate. We also investigate the effect of preheat temperature and IR stimulation power on the
decay shape and conclude that the data can be explained in terms of either a single- or multiple-trap model. We present evidence
that may suggest that at least part of pIRIR signal is derived from a high temperature trap (∼550°C thermoluminescence (TL)
peak), although again the data can also be explained in terms of a single-trap model. Finally, we present dose response curves
and characteristic curvature constants (D0) values for various IRSL signals and conclude that the more stable signals saturate more quickly than the less stable signals
and that the initial and final signals saturate at approximately the same level. 相似文献
996.
In recent years, a team at the Geology and Paleogeography Unit, Marine Sciences Institute, University of Szczecin, has been
performing geological, geochronological and paleogeographic surveys in (i) the Szczecin Lagoon and Świna Gate Sandbar and
(ii) the estuary section of the Rega river valley near Mrzeżyno. These studies have helped to examine and identify not only
the distribution of fossil marine sediments but also their lithological and sedimentological characteristics. The age of marine
ingressions and regressions in the coastal zone of the Pomeranian Bay were determined using approximately 170 radiocarbon
assays. 相似文献
997.
Ioannis Liritzis 《Geochronometria》2011,38(3):292-302
Daylight radiation resets luminescence ‘clock’ to zero on rock surfaces, but transmission depends on the transparency of the
rock. On burial, surfaces are no longer exposed to daylight and accumulation of trapped electrons takes place till the excavation.
This reduction of luminescence as a function of depth fulfils the prerequisite criterion of daylight bleaching. Thus rock
artefacts and monuments follow similar bleaching rationale as those for sediments. In limestone and marble, daylight can reach
depths of 0.5–1 mm and up to 16 mm respectively, while for other igneous rocks e.g. quartz in granites, partial bleaching
occurs up to 5mm depth under several hours of daylight exposures and almost complete beaching is achieved in the first 1 mm
within about 1 min daylight exposure. The ‘quartz technique’ for limestone monuments containing traces of quartz enables their
dating with Optically Stimulated Luminescence (OSL) techniques. The surface luminescence (thermoluminescence, TL or OSL) dating
has been developed and further refined on various aspects of equivalent dose determination, complex radiation geometry, incomplete
bleaching etc. A historical review of the development including important applications, along with some methodological aspects
are discussed. 相似文献
998.
Tobias Lauer Matthias Krbetschek Manfred Frechen Sumiko Tsukamoto Christian Hoselmann Michael Weidenfeller 《Geochronometria》2011,38(1):23-33
The infrared radiofluorescence (IR-RF) dating technique was applied to eight fluvial samples that were collected from two
sediment cores at the Heidelberg Basin located near Viernheim and Ludwigshafen in southwest Germany. Based on the IR-RF derived
ages of the samples it was possible to establish a chronological framework for the Mid-Pleistocene fluvial deposits of the
Heidelberg Basin. The results allow us to distinguish between four main periods of aggradation. The lowermost sample taken
from 100 m core depth lead to an IR-RF age of 643 ± 28 ka pointing to a Cromerian period of aggradation (OIS 17–16). For the
Elsterian it is now possible to distinguish between two aggradation periods, one occurring during the Lower Elsterian period
(OIS 15) and a second during the Upper Elsterian period (OIS 12–11). For the so called Upper interlayer (or “Oberer Zwischenhorizont”
— a layer of organic-rich and finer-grained deposits), the IR-RF results point to a deposition age of around 300 ka, with
samples taken directly on top and out of this layer yielding IR-RF ages of 288 ± 19 ka and 302 ± 19 ka, respectively. Hence,
the measured IR-RF ages clearly point to a deposition during the Lower Saalian period (OIS 9–8) whereas earlier studies assumed
a Cromerian age for the sediments of the Upper Interlayer based on pollen records and also mollusc fauna. The new IR-RF dataset
indicates that significant hiatuses are present within the fluvial sediment successions. In particular the Eemian and Upper
Saalian deposits are missing in this part of the northern Upper Rhine Graben, as the 300 ka deposits are directly overlain
by Weichselian fluvial sediments. It is obvious that time periods of increased fluvial aggradation were interrupted by time
periods of almost no aggradation or erosion which should have been mainly triggered by phases of increased and decreased subsidence
of the Heidelberg Basin. 相似文献
999.
Derek W. G. Sears 《Geochronometria》2011,38(3):303-313
Early work on meteorite thermoluminescence, influenced by pottery dating and dosimetry applications, demonstrated a relationship
between natural thermoluminescence and (1) the orbital perihelion of a meteorite and (2) the terrestrial age (time since fall)
of a meteorite. For 14 years natural TL measurements were routinely made on newly recovered Antarctic meteorites to help identify
unusual thermal and radiation histories, and to sort them by terrestrial age and perihelion. Two examples of the value of
such data are presented, an Antarctic meteorite that underwent a major orbit change prior to fall and the collection mechanics
of meteorites at the Lewis Cliff collection site. A second major area of focus for meteorite TL, that has no non-meteorite
heritage, is the use of their induced TL to provide an extraordinarily sensitive and quantitative means of exploring metamorphic
intensity and palaeothermometry. While especially valuable for unequilibrated ordinary chondrites, these types of measurement
have proved useful with virtually every major class of meteorite, asteroidal and planetary. The challenge now is to extend
the technique to small particles, micrometeorites, interplanetary dust particles, and cometary particles. 相似文献
1000.
Kenneth W. Glennie Steven G. Fryberger Caroline Hern Nicholas Lancaster James T. Teller Vachaspati P. Pandey Ashok K. Singhvi 《Geochronometria》2011,38(3):259-271
In the Wahiba Sands of eastern Oman, luminescence dating of sands enables us to relate wind activity to climatic variations
and the monsoon cycle. These changes resulted from Polar glacial/interglacial cyclicity and changes in global sea levels and
wind strengths. Luminescence dates show that development of the Sands began over 230 ka ago when the sand-driving winds were
the locally arid, northward-blowing SW Monsoon. 相似文献