64 resultados para Teorema Egregium de Gauss


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Magnetic polarity stratigraphies for Sites 980-984 are based on shipboard measurements from the pass-through magnetometer after alternating field (AF) demagnetization at a peak field of 25 mT and shore-based stepwise AF demagnetization of discrete samples. The characteristic magnetization component was determined after AF demagnetization removed the steep downward drill-string-related magnetic overprint. Peak AF fields in the 20-30 mT range were required to resolve the component, carried by magnetite, that was used to produce unambiguous Pliocene-Pleistocene magnetic stratigraphies at all five sites. At Sites 980 and 983, magnetic stratigraphies were resolved to the base of the recovered advanced hydraulic piston corer (APC) section, which lies in the Matuyama Chron (1r.2r) and Olduvai Subchron (2n), respectively. At Sites 981 and 982, magnetization intensities decrease sharply in the normal polarity zone corresponding to the Gauss Chron (2An), and magnetic stratigraphies below this level could not be resolved. At Site 984, the resolution of magnetic stratigraphy was curtailed at ~250 meters below seafloor (Olduvai Subchron) by core deformation at the base of the APC section and in the underlying extended core barrel section. As the magnetic stratigraphies at all four sites are unequivocal, polarity chron interpretations can be made without aid from the biostratigraphy. Mean sedimentation rates within polarity chrons have been calculated and Pliocene-Pleistocene biomagnetostratigraphic correlations tested.

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A well-documented, publicly available, global data set of surface ocean carbon dioxide (CO2) parameters has been called for by international groups for nearly two decades. The Surface Ocean CO2 Atlas (SOCAT) project was initiated by the international marine carbon science community in 2007 with the aim of providing a comprehensive, publicly available, regularly updated, global data set of marine surface CO2, which had been subject to quality control (QC). Many additional CO2 data, not yet made public via the Carbon Dioxide Information Analysis Center (CDIAC), were retrieved from data originators, public websites and other data centres. All data were put in a uniform format following a strict protocol. Quality control was carried out according to clearly defined criteria. Regional specialists performed the quality control, using state-of-the-art web-based tools, specially developed for accomplishing this global team effort. SOCAT version 1.5 was made public in September 2011 and holds 6.3 million quality controlled surface CO2 data points from the global oceans and coastal seas, spanning four decades (1968-2007). Three types of data products are available: individual cruise files, a merged complete data set and gridded products. With the rapid expansion of marine CO2 data collection and the importance of quantifying net global oceanic CO2 uptake and its changes, sustained data synthesis and data access are priorities.

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In der vorliegenden Arbeit wird nach morphologischen und sedimentpetrographischen Methoden die Entwässerung der würmzeitlichen Eisrandlagen Mittelholsteins untersucht. Das Untersuchungsgebiet liegt im Mittelteil des nördlichen Holsteins. Im Norden und Osten schließt es etwa mit den Orten Gr. Vollstedt-Blumenthal-Stolpe-Tensfeld, im Süden mit dem Tal der Tensfelder und Oster- bzw. Bram-Au, während es im Westen durch die Höhen der Riß-Moränen zwischen Kellinghusen und Brammer abgegrenzt wird. Morphologisch zeigt sich eine Dreiteilung: im Norden und Osten die würmzeitliche Jungmoräne, im Westen und Süden die rißzeitliche Altmoräne, zwischen beiden die Sander- und Abflussebenen der Würm-Vereisung.