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991.
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
992.
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
993.
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
994.
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
995.
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
996.
In the OSL dating of sediment, the scatter in equivalent dose (D
e) between grains is almost always larger than would be expected due to counting statistics alone. Some scatter may be caused
by insufficient (partial) bleaching of some of the grains prior to deposition. In order to date partially bleached sediment,
it is essential to estimate the amount of scatter caused by other processes (e.g. grain-to-grain variability in the natural
dose rate). Measurements of such scatter are performed at the single-grain level; by contrast, most OSL dating is performed
on multi-grain subsamples, for which grain-to-grain scatter is reduced through averaging. 相似文献
997.
Laura M. López Aylen Capparelli Axel Emil Nielsen 《Archaeological and Anthropological Sciences》2011,3(1):49-70
The aim of this paper is to generate information to assist in the archaeobotanical recognition of post-harvest processing
activities related with different enhancement and consumption patterns of quinoa in the Central Andes. Enhancement of the
grains involves what local people call “mejorado de los granos”. Their main purpose is to reduce as far as possible the presence
of saponins, a toxic metabolite, in the grain. Ethnobotanical data were recorded in the village of Villa Candelaria (Southern
Bolivian highlands) through the application of standard ethnographic techniques. The types of grain enhancement vary depending
on the meal that people want to prepare. We registered three different quinoa enhancements based on intended consumption,
(1) as a whole seed, (2) in soups or (3) as pitu (a kind of toasted refined flour). Laboratory analysis aimed at identifying distinctive features of grains in different processing
stages, as well as evaluating the effects of charring. For both desiccated and charred remains, quinoa processed for pitu can be distinguished from that for whole seed/soup. As a case study, archaeological grains of the pre-Inka site of Churupata,
located 3 km from Villa Candelaria, were interpreted as quinoa prepared for consumption as whole seed/soup. 相似文献
998.
Collagen fingerprinting of archaeological bone and teeth remains from Domuztepe,South Eastern Turkey
We applied a recently developed method of collagen peptide mass fingerprinting for taxonomic identification in faunal remains
to 111 specimens from the Neolithic site of Domuztepe in southeastern Turkey. Advances on the published technique allow us
to move beyond the key domesticated fauna (sheep, goat, pig and cattle) to include non-domesticates (deer and gazelle, as
well as humans). As the animal economy of Domuztepe was dominated by domestic sheep and goats, a large number of the samples
tested were morphologically indistinguishable sheep/goat remains. A number of samples represented elements that provide information
on age (i.e., mandibles) or sex (pelvis); thus, this represents the first major study to attempt to improve kill-off profiles
using collagen fingerprinting. We also show that the collagen extracted from dentine is equally amenable to the proposed methodology
as bone collagen. 相似文献
999.
Ximena S. Villagran Andrea L. Balbo Marco Madella Assumpció Vila Jordi Estevez 《Archaeological and Anthropological Sciences》2011,3(4):357-378
Based on ethnographic accounts from the eighteenth to the twentieth century, functional areas have been identified within
Fueginian shell middens. In this context, archaeological microfacies acquire a functional meaning when the microscopic record
is compared to information gathered from ethnology, macroscopic observations made during excavation, and experimental modern
analogues. All these lines of evidence were combined for the first time at Tunel VII, an eighteenth/nineteenth century shell
midden occupied repeatedly by Yamana people, the last hunter–gatherer–fisher groups of the Beagle Channel. The sampling strategy involved three sets of samples:
(1) two stratigraphical columns taken from the hut “entrance” and from a portion of the shell midden (i.e., the surrounding
refuse shell ring), (2) thin sections from five hearths representing successive phases of frequentation of the hut, and (3)
experimental burnt valves of Mytilus edulis, the main malacological component of the site. Comparison of microfacies from groups (1) and (2) provided microscopic indicators
to distinguish between shell dumping areas and occupation surfaces. Comparison of microfacies within columns from group (1)
allowed recognizing periods of site abandonment and periods of more intense/longer site frequentation. The experimental samples
from M. edulis served as a reference to characterize the five central hearths in terms of maximum burning temperatures reached. Different
burning structures were correlated to the season of hut frequentation and to their location (and function) within different
portions of the hut. The intra-site micromorphological comparison strategy within a well-documented ethnohistorical context
provides valuable indicators for the identification of functional areas in archaeological contexts when ethnographical information
is not available. 相似文献
1000.
Nienke Laura van Doorn Hege Hollund Matthew J. Collins 《Archaeological and Anthropological Sciences》2011,3(3):281-289
Bone collagen is found throughout most of the archaeological record. Under experimental conditions, collagen is apparently
preserved as an intact molecule, with amino acid compositions and isotopic profiles only changing when almost all of the protein
is lost. The ubiquity of collagen in archaeological bone has lead to the development of the use of collagen peptide mass fingerprints
for the identification of bone fragments—Zooarchaeology by Mass Spectrometry (ZooMS). We report a novel, but a simple method
for the partial extraction of collagen for ZooMS that uses ammonium bicarbonate buffer but avoids demineralisation. We compared
conventional acid demineralisation with ammonium bicarbonate buffer extraction to test ZooMS in a range of modern and archaeological
bone samples. The sensitivity of the current generation of mass spectrometers is high enough for the non-destructive buffer
method to extract sufficient collagen for ZooMS. We envisage that a particular advantage of this method is that it leaves
worked bone artefacts effectively undamaged post-treatment, suitable for subsequent analysis or museum storage or display.
Furthermore, it may have potential as a screening tool to aid curators in the selection of material for more advanced molecular
analysis—such as DNA sequencing. 相似文献