Исследование температурного поведения сцинтилляционного детектора NaI(Tl)

Объектом исследования являются сцинтилляционные детекторы типа БДКГ для исследования влияния температуры на их показания. Целью данной работы является исследование температурной зависимости показаний детектора гамма-излучения в климатической камере, для расчета поправочного коэффициента на колебания температуры окружающей среды. Был проведен эксперимент в климатической камере, полученные результаты подтверждают некорректность показаний исследуемых детекторов. На основе экспериментальных данных рассчитан коэффициент корректировки на температуры для перерасчета скорости счета импульсов в мощность дозы.The object of the study is scintillation detectors of the BDKG type to study the effect of temperature on their readings. The aim of this work is to study the temperature dependence of the gamma-ray detector readings in a climate chamber to calculate the correction coefficient for fluctuations in ambient temperature. An experiment was conducted in a climatic chamber, the obtained results confirm the incorrectness of of the studied detectors readings . Based on the experimental data, the temperature correction coefficient was calculated to recalculate the pulse count rate in the dose rate

Amphibolites of the KTB target area Oberpfalz, Bavaria

No abstract availabl

Geochemical characteristics of metabasites in different tectonic units of the North-East-Bavarian crystalline basement

Comprehensive geochemical investigations of rnetabasites yielded constraints for a correlation of, or discrimination between the different tectonic units within the northeast Bavarian crystalline basement. The Münchberg nappe pile consists of at least five large tectonic units which exhibit differences in lithology, in part also in metamorphie grade and in metamorphie history. The metabasites in each of these nappes show their own, significant geochemical characteristics. The lowermost tectonic unit, the Bavarian lithofacies, includes the anchimetamorphie Ordovician Randschieferserie which contains alkaline basalts. In their geochemistry, they are sirnilar to the metabasites of the Fichtelgebirge crystalline complex in the autochthonous Saxo-thuringian. The next higher tectonic unit of the Münchberg nappe pile, the Prasinit-Phyllit-Serie contains metabasites which can be derived from subalkaline basalts with a clear calc-alkaline tendency. There is a striking geochemical resemblance to the metabasites of the Erbendorf Greenschist Zone (EGZ) underscorinq the similar lithology of both allochthonous units which appear to be in a similar tectonic position. The Randamphibolit-Serie higher up in the Münchberg nappe pile consists of metabasites with tholeiitic characteristics and a pronounced differentiation trend. The next higher tectonic unit, the Liegendserie of the Münchberg gneiss cornplex s. str., contains metagabbros to metagabbronorites with a high-Al basaltic composition. The amphibolites and banded hornblende gneisses of the overlying Hangendserie are of subalkaline basaltic character with calc-alkaline affinity. The Zone Erbendorf-Vohenstrauss (ZEV) is currently regarded as an allochthonous unit equivalent to the higher crystalline nappes of the Münchberg pile. However, the geochemical character of the metabasites do not encourage such a correlation. Neither the schistose and striped amphibolites nor the flaseramphibolites of the ZEV with their N-KORB and E-MORB character respectively, find convincing counterparts in the crystalline nappes of the Münchberg pile. However, an interestingly close resemblance exists between the schistose and striped amphibolites in the ZEV, on the one hand, and in the autochthonous Zone Tirschenreuth- Mähring (ZTM) and the adjacent Moldanubian sensu strictu, on the other. Owing to the absence of age criteria, our results cannot be used, so far, to reconstruct the paleogeographical position of the individual tectonic units, based on the geochemical characteristics of their respective metabasites

Geochemistry of metabasites and element mobility

No abstract availabl

Aragonite-Bearing Blueschists on Arki Island, Dodecanese, Greece

On the island of Arki, aragonite-bearing blueschists are recorded within the Temenia Nappe forming the lowermost unit of the Dodecanese nappe pile. The critical mineral assemblages glaucophane - phengite - chlorite - albite - epidote - aragonite (- calcite) in the blueschists and albite - epidote - chlorite - phengite - winchite - calcite (probably after initial aragonite) in the related, isofacial greenschists indicate a subduction-related metamorphism with pressures of 7 to 10 kbar and temperatures of 300 to 400-degrees-C. The geological significance of this new blueschist occurrence is discussed

Polymetamorphic Evolution of Pre-Alpidic Basement Rocks on the Island of Sikinos (Cyclades, Greece)

On the island of Sikinos, Attic-Cycladic crystalline complex, remnants of a pre-Alpidic basement complex, initially consisting of a sedimentary sequence intruded by granodiorites and diorites are preserved. The basement complex under-went polyphase deformation and metamorphism. Based on textural and mineralogical evidence in the metasediments of the basement complex, three metamorphic events can be distinguished: A pre-Alpidic amphibolite facies metamorphism at peak temperatures of about 570 - 650-degrees-C and poorly constrained pressures of around 5 kbar, an Alpidic high-pressure event under conditions of the epidote-blueschist facies at minimum pressures of 10 kbar in an assumed temperature range of 450 - 500-degrees-C, and a subsequent Barrovian facies overprint under greenschist-facies conditions, at temperatures of 440 - 480-degrees-C and minimum pressures of 5 kbar. Owing to incomplete re-equilibration, these P - T estimates must be regarded with caution, although, they agree well with other estimates in the Attic-Cycladic crystalline complex

K-Ar geochronology of the East-Bavarian basement

No abstract availabl