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[en] It is proposed that unstable temperature conditions in the Late Wuchiapingian and Early Changhsingian (Late Permian) changed in the Boreal Superrealm to less contrasting climatic conditions in the Late Changhsingian and Early Induan (the formation time of trap formation of the Siberian Platform), with a stable trend of increasing temperature in the Early Triassic. The problem of the absence of signs of mass extinction of marine organisms at the Permian–Triassic boundary in the Boreal Superrealm is discussed.
[en] The basis of the Mg/Ca ocean paleothermometer is the thermodynamic substitution of the divalent cation Mg for Ca into biogenic calcite, the potential of which as a paleothermometer has been known for nearly 100 years. However, only relatively recently have technological advances resulted in routine application of this technique to extracting past ocean temperatures, principally from the calcite tests of microfossils called foraminifera. (author). 9 figs.
[en] The author introduces the method and principle of AFTA, i.e. annealing characteristics. Through analysing the AFT data of the six Jurassic samples from the Well Bonan-1 and the Well Yancan-1 in the Yanqi Basin, the authors conclude that in the north sag, the thickness of Cenozoic group was generally more than 2000 meters, the north sag was situated in Cenozoic compensation geothermal district, and the maximum palaeo-temperature of the middle-lower Jurassic was about 70-110 degree C in late Cenozoic; while in the south sag, the thickness of Cenozoic group was generally less than 1500 meters, the south sag was situated in Cenozoic deficient geothermal district, and the maximum palaeo-temperature of the lower middle lower Jurassic was about 80-110 degree C in latest Jurassic. The AFT ages show that in the north sag, the uplift event took place in late Cretaceous, while in the south sag, the uplift event took place in early Cretaceous. Therefore the main uplift event of the Yanqi Basin took place in Cretaceous period, and the uplift of the south was earlier than that of the north
[en] The aim of the work was to perform paleotemperature reconstructions for the Late Pleistocene and Holocene of Kotelny Island according to oxygen isotope analysis of syngenetic ice wedges. Variations of δ18O in the Late Pleistocene ice wedges formed on Kotelny Island are significant, exceeding 8‰ (from –30‰ to –22.9‰), while they are insignificant at –1.5‰ (from –23.1‰ to –21.6‰) for those in the Holocene. Reconstructions showed that the mean January temperature in the Late Pleistocene changed over 8 to 13°C. The mean annual temperature of frozen soils was about –19 or –20°C in the Late Pleistocene, and about –13 to –15°C in the Holocene, while the current temperature is about –14°C.
[en] The problem of the reconstruction of past surface temperatures from the measured temperature depth profiles has been studied in the paper. The solution of this problem does not have properties of stability and uniqueness. An algorithm of the reconstruction of past surface temperatures that is stable and unique has been developed
[ru]Рассматривается задача реконструкции прошлых температур поверхности по данным измерений температуры в скважинах. Решение этой задачи в общем виде не обладает свойством единственности и устойчивости. В работе предложен алгоритм реконструкции прошлых температур, позволяющий получать решение, обладающее этими свойствами
[en] The relative significance of the 20th-century climatic and environmental changes must be assessed form the long-term global-scale perspective available from a spectrum of proxy histories. In many cases geochemical proxies in sediments are needed to supplement the established use of the stable isotope analyses for paleotemperature and paleo-hydrological modeling so as to understand the past environment conditions and evaluate predictive models of climate. The stable carbon isotope fractionation during photosynthesis and the system CO2 (gas)-CO2-(aqueous)-HCO3- (aqueous) are reviewed; and application of the stable carbon isotope to reconstruction of palaeo-climatic and palaeo-environmental changes, especially CO2 levels during the late Quaternary are discussed
[en] Oxygen and carbon isotopic stratigraphies are presented from both benthic and planktic foraminifera for the late early Miocene to earliest Pliocene interval (c. 19-5 Ma) of intermediate water-depth DSDP Site 593 in the southern Tasman Sea. The benthic values are interpreted as recording Miocene Southern Component Intermediate Water, while the planktic species record the Miocene mode and surface water signals. Comparisons are made between temperate Site 593 and the intermediate-depth polar Site 747 in the southern Indian Ocean. Glacial Mi zones Mi1b-Mi6, representing extreme glacial events, are evident in both the Site 593 intermediate and surface water records. Miocene Southern Component Intermediate Water δ18O values are generally lighter than the Holocene equivalent (Antarctic Intermediate Water), indicating slightly warmer intermediate waters and/ or less global ice volume. The benthic-planktic gradient is interpreted as indicating a less stratified Tasman Sea during the Miocene. The benthic δ13C record contains most of the global carbon maxima (CM) events, CM1-7 (CM1-6 = the Monterey Excursion). Like global deep-water records, the Tasman Sea intermediate water δ13C values indicate that most CM events correspond with Mi glacials, including Mi4 at Site 593, not reported previously. Intermediate waters play an important role in propagating climatic changes from the polar regions to the tropics, and the Site 593 dataset provides a full water column record of the structure of Miocene intermediate to surface watermasses prior to the modern situation. (author). 132 refs., 8 figs., 4 tabs
[en] The stable oxygen and hydrogen isotope composition of Late Pleistocene syngenetic ice wedges of Batagai yedoma are studied, and detailed isotope diagrams are obtained. The reconstructed mean January paleotemperature is lower than –51°С, which completely confirms the validity of the paleotemperature maps made earlier for the period of 30–25 ka BP where the location of the Batagai section within the isotherm of –48°C.
[en] Research highlights: → A 2-year monitoring to investigate the seasonal variation of fatty acids in cave drip water. → Microbes are the dominant source for fatty acids in drip water. → The relative abundance of mono-unsaturated responds negatively with external air temperature. - Abstract: In order to investigate how lipids in cave water respond to seasonal climate change, drip water samples were collected from 2006 to 2008 in Heshang Cave, central China for fatty acid analysis. These lipids are abundant in the drip water. Their compositions are dominated by lower-molecular-weight nC16:0, nC18:0 and nC14:0 acids, together with mono-unsaturated nC18:1, nC16:1 and nC14:1. Analysis of one water sample revealed marked differences between the dissolved and particulate fractions. The dissolved fraction contains total fatty acids one order of magnitude higher than that of the particulate fraction. The distributional patterns of the fatty acids suggest that microbes living in the overlying soils and/or groundwater system contribute most fatty acids to the drip water. This 2-a monitoring experiment reveals that the abundance of mono-unsaturated fatty acids relative to the saturated homologues (nC16:1/nC16:0 and nC18:1/nC18:0) relate inversely to the changes of synchronous external air temperature. Higher values occur under cold conditions (winter/spring), while lower values appear in warm intervals (summer). Further studies are needed to elucidate the dynamic processes by which the external temperature affects fatty acids in drip water and to confirm the potential application of fatty acid ratios such as nC16:1/nC16:0 and nC18:1/nC18:0 in paleotemperature reconstructions.
[en] Paleotemperature fluctuation in tropical zone (centennial and decad al scale) has been known. It's based on stable isotopic analysis from each of unconformity zones. Those boundaries have derived on reef units of shallows marine reef complex of Paciran Formation, Tuban area in Northeast Java Basin. From 25 samples have been choosen on undeformed calcite and analyzed by oxygen and carbon stable isotope. It used to validizing a sea level changes during the formation to Reef 1 to Reef 17 from Paciran formation with sea surface temperature (SST) since 4 Ma until now. On early forming of Reef 1 to Reef 3 (since 4 Ma - 2,88 Ma), sea level occurred marine flooding surface. Since the formation of reef 4 (2,59 Ma) to Reef 8 (1,4 Ma) occurred stagnant temperature and almost to warmer condition. Then, δ18O have arise up drastically to 5 0/00 and shows warmer condition to Reef 8 formation, in contrary, the sea level have been arised to Reef 10 formation (0,7 Ma). The temperature have been fluctuated between 0,5o and 1oC until the formation of Reef 17 (Early Holocene) and continued to Reef 17 formation at 2oC based on the rapidity sampling of Po rites sp. Wholly, in centennial scale, since the formation of Reef 4 (2,59 Ma) to Reef 17 (1 Ma), the curve of oxygen stable isotope shows decrease or cooler condition. Those condition have conducted to sea level drop since the formation to Reef 7 and Reef 8. There are 4 periods of interglacial since the formation of Reef 4. The warmer condition indicated since the formation of Reef 9, Reef 11 and Reef 17. Recently, a curve of oxygen isotopes reveals warmer drastically or sea level have been arisen. (author)