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21.
Dendrochronological methods can be applied to the reconstruction of different types of environmental events such as climate changes, fires, glacier movements, floods, earthquakes, volcano activity. In the field of geomorphology dendrochronology is increasingly frequently used for the absolute dating of different types of mass-movements (rock falls, landslides and debris flows, etc.). Trees growing on slopes transformed by mass-movements are tilted and wounded while their stems and root systems are exposed or buried under sediment. These events are recorded in wood anatomy as eccentric growth, reaction wood, scar overgrowth by callous tissue, changes in cell size or adventitious root production. Dating changes in wood anatomy allows to date and precisely reconstruct the spatial and temporal occurrence of mass-movements with at least one year resolution. The paper provides a review of existing dendrochronological tools used in geomorphology and also an example of the application of eccentric tree-growth to reconstruct landsliding. Using tree-ring eccentricity allows to (1) obtain a dynamic depiction of slopes, (2) study landslide activity, not only contemporary, but also in the last tens of hundreds of years (depending on the stand age).  相似文献   
22.
Lime mortars may contain carbon from different origins. If the mortars are made of totally burnt lime, radiocarbon dating yields the true age of building construction. The presence of carbonaceous aggregates gives the so-called dead carbon effect, which may generate older ages. Another source of carbon is charcoal present in mortars. An attempt has been made to apply the radiocarbon method to mortars of archaeologically estimated age from the Dead Sea region. Petrographical analyses of these samples show the carbonaceous character of the binder and large amounts of limestone aggregate. Determination of the mineral composition of the mortars and comparison with the geology of the surrounding, allows the provenance of the raw materials to be identified. They probably represent the Cretaceous rocks of the Judea Group. Separate radiocarbon dates were made on bulk mortar samples, binder, charcoal fragments and separated fractions from mortars. In the case of binder-aggregate mixture the reservoir effect correction has been applied.  相似文献   
23.
An ornamented artefact made of antler, found in the environs of ?widwin (Pomerania, NW Poland), was subject to structural and environmental analysis. Radiocarbon dating (10?700 ± 60 BP or 10?910–10?680 cal. BC) places it in the Final Palaeolithic, at the end of Weichselian (boundary of the Allerød and Younger Dryas). The surface of the artefact bears a complex ornament of zigzag lines and an anthropomorphic drawing, representing most probably a woman with spread legs. Palynological analysis of the deposit in which the object was found indicates forest communities (pine-birch forests) with some open areas, in a cool climate. Ultrastructural examination points to the elk Alces alces (Linnaeus, 1758) as the source species; the antler was at the stage of intense growth which indicates that the elk was killed or died in the spring-summer period. The antler was large, and the object made of it was used for a long time, playing a role in rituals and symbolic culture of a hunting group. The ornamentation shows an affinity to the early Mesolithic art and makes it possible to better trace the relations between the hunters of the late Pleistocene and those of the early Holocene.  相似文献   
24.
The history of the interlaboratory comparison of TL dating results in Poland started in the 1980s. At that time the Lublin, Warsaw and Silesian laboratories made the first attempts at TL dating of the same loess samples from the Odonów profile. However, the cooperation ceased for many years due to great differences in the obtained TL age estimates. The next interlaboratory comparisons were made in the years 2000–2009 for the loess samples from several Polish (Dybawka, Tarnawce, Dankowice, Biały Kościół) and Ukrainian (Boyanychi, Halych, Velykyj Hlybochok, Yezupil) profiles. Most of the compared dates, obtained for the loess deposits from the Upper Pleistocene and younger part of the Middle Pleistocene, were consistent. This encouraged us to undertake the Gdańsk-Lublin interlaboratory cooperation in dating of 200-700 ka old loess deposits. Nine samples were taken from the Ukrainian profile Mamalyha 2 in 2009 for this purpose. The TL dating results indicate that comparable dates are obtained in two laboratories for loess deposits younger than 300 ka BP. The TL signal obtained in the Gdańsk laboratory for the samples older than 300 ka BP was saturated so such samples should not be dated by the multi-aliquot regeneration method. The results obtained in the Lublin laboratory for these deposits (489–682 ka) confirm that it is possible to date loess deposits older than 500 ka. It probably results from the use of total-bleach method with preheating at 160°C for the equivalent dose determination.  相似文献   
25.
The present study focuses on investigations carried out in the Late Vistulian succession of the Warta River deposits (central Poland) in which a horizon of subfossil trees was excavated. Prelim-inary conclusions on time record and past environmental conditions of a forest existence determined from radiocarbon dating, pollen analyses and geological evidence appear promising with view of tree-ring chronologies.  相似文献   
26.
Absolute dating using luminescence methods is widely applicable in geology, geomorphology, palaeogeography and in archaeology in establishing ages of sediments and archaeological artefacts. By creating absolute time scales for different events in the history of Earth scientists are able to reconstruct changes in climate and environment in the past, and the history of colonization and development of culture.  相似文献   
27.
We present the first analysis of the influence of climate change on carbon and oxygen isotope fractionation factors for two saccharides (glucose and α-cellulose) of pine wood. The conifers grew in the Niepo?omice Forest in Poland and the annual rings covered a time span from 1935 to 2000 AD. Glucose samples from acid hydrolysis of α-cellulose were extracted from annual tree rings. The carbon and oxygen isotope fractionation factors between glucose and α-cellulose were not stable over time. The mean value for the carbon isotope fractionation factors between glucose and α-cellulose was greater than unity. The mean value for the oxygen isotope fractionation factors between glucose and α-cellulose was lower than unity. We established, with respect to climate change, the significance of the interannual and intraannual variation in the carbon and oxygen isotope fractionation factors between both saccharides. We used moving interval correlation results for May of the previous year through September of the current year using a base length of 48 years. The relationship with summer temperature is the main climate signal in the carbon isotope fractionation factor between glucose and α-cellulose. The relationship with autumn sunshine is the main climate signal in the oxygen isotope fractionation factor between glucose and α-cellulose for the tree ring chronology.  相似文献   
28.
The cliff in Ustka is an active one. The area is one of the most eroded sea shores of the Polish coast. The Ustka Cliff mainly consists of Holocene sandy deposits, but its basis is built of glacial till and clay. Field search allowed to recognize the structure and sedimentary conditions of Holocene deposits exposed in the cliff. A comparison of dating results obtained for fossil soils and peat as well as aeolian deposits, using 14C and TL methods, respectively, with available literature records is presented. The evaluation of results obtained allowed to define three main dune-forming phases for the first time for this part of the Polish coast. During the research studies new data on the processes and environmental conditions was gained and the development of structure of the area during the last 10 thousand years was reconstructed. The analysis of available data from other sections of the southern Baltic coast shows that results obtained are age similar to those determined for the ?eba Spit. The research is part of a project concerning the geomorphology of the Ustka Bay.  相似文献   
29.
In September 1939, Poland was invaded by Nazi Germany and the Soviet Union, starting World War II. The war’s end in 1945 marked not the true liberation of the country, but the beginning of a period of Soviet domination that ended only in 1989. As a result, for forty-five years of Polish history, the alliance made by the Hitler with Stalin in 1939 and its tragic consequences for Poland were taboo across society. Polish filmmakers presenting the beginning of World War II were constrained by realities of the Communist state and its own historical narratives. These films reflect what happened to their country in 1939 and highlight the political changes that occurred within Poland under Communist rule, as well as the impact of shifts in the regime itself. The most significant period in this regard was 1945–67, when the outbreak of war was first presented following the end of Stalinism, emerging as a component of national memory both generally and for the Communist authorities.  相似文献   
30.
Further Neolithic encampments and settlements have been explored by the Combined Prehistoric Expedition in the Nabta Playa Basin on the South–Western Desert border around 100 km west of the Nile Valley. The perfectly preserved stratigraphic setting of the new site, numerous hearths and traces of dwellings, rich cultural material including pottery, radiocarbon dates and presence of bone remains render site E–06–1 an exception on the map of settlements of El Adam communities.  相似文献   
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