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61.
Biostratigraphic and palaeomagnetic research has been carried out on selected profiles in North-Western Germany and Central Italy in order to correlate Plio-Pleistocene sections.Around the Réunion subchronozone, vegetation in the Valle Ricca was dominated by a mountain forest type pointing to cool climatic conditions. In the Lower Rhine Basin vegetation had a slightly warmer character, but was also dominated strongly by a mountain type of forest vegetation, characteristic of cooler summers and higher precipitation than at present.Two warmer periods have been determined in the Central Italian profiles; the youngest around the Olduvai reversal, should correspond to the youngest Tiglian beds of the Lower Rhine Basin.Deposits older than the Réunion subzone have not been found in the Valle Ricca. In the Lower Rhine Basin, on the other hand, the Gauss-Matuyama boundary is located between the uppermost Pliocene, the Reuverian C and the Praetiglian.  相似文献   
62.
This paper describes an uncomplicated sampling technique for ultratrace element analysis of coastal and surface seawaters (maximum depth 100 m). The sampler system is very easy to operate. To prevent contamination problems, interchangeable 500-ml Teflon bottles are used as both sampling and storage vessels. The seawater samples are stabilized in situ by preacidifying the sampling bottles. For the determination of mercury in seawater the desired system has been developed: sampling bottle = storage bottle = reaction vessel.  相似文献   
63.
The question whether paleoclimatic systems are governed by a small number of significant variables (low-dimensional systems) is of importance for modeling such systems. As indicators for global Plio-/Pleistocene climate variability, four marine, sedimentary oxygen isotope time series are analyzed with regard to their dimensionality using a modified Grassberger-Procaccia algorithm. An artificial, low-dimensional chaotic time series (Hénon map) is included for the validation of the method. In order to extract equidistant data the raw data are interpolated with the Akima-subspline method since this method minimizes the change in variance due to the interpolation. The nonlinear least-squares Gauss-Marquardt regression method is used instead of the linear least-squares fit to the logarithmically transformed points, in order to acquire an unbiased estimate of the correlation dimension. The dependences of the estimated correlation dimension on the embedding dimension do not indicate a small number (i.e., less than 5) of influencing variables on the investigated paleoclimatic system, whereas the low dimension for the Hénon map is verified (dimension 1.22–1.28). Because of the limited amount of data in the oxygen isotope records, dimensions greater than about 5 cannot be examined.  相似文献   
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Photographs of Comet Bennett 1969i taken in the dust-scattered continuum reveal that the dust particles, leading to the formation of the type II tail, leave the vicinity of the nucleus only within a certain cone with the aperture in the direction to the Sun. Three parabolic envelopes embracing the nucleus are formed by the dust (vertex always about on the radius vector) reaching distances from the nucleus of 30 000, 60 000 and 100 000 km.There exists no relation between the production and motion of this dust and the production and motion of the neutral coma gases. The cone of expulsion of the dust is identical with the cone of expulsion for the ions leading to the formation of the type I tail. Dust- and ion envelopes have, however, different kinematical properties. The cone of expulsion is identical with Bessel's Ausströmungskegel of visible matter observed by him in Comet Halley 1835.Comet Bennett is compared with Comet Halley 1910; they are related in many respects although Comet Halley had a lower dust production than the Comet Bennett.We ascribe to the dust particles of the tail II from the beginning of the expulsion an electrical charge.  相似文献   
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There is no generally accepted evolutionary scheme for high mass star formation yet. A simple approach to address this problem is to cover several of the known stages during the formation of massive stars in the same cloud and then investigate their properties trying to construct an evolutionary sequence. Here we present such a project conducted with complementary APEX and ATCA observations. These observations show a compact and bright single hot core in the G327.3-0.6 region on a 0.03 pc scale with a mass of 500 M and 0.5–1.5 105 L. Additionally a clumpy filament is seen in N2H+. Together with cm continuum observations, the data reveal like pearls on a string several stages of massive star formation, with likely the youngest stages hiding in the cold N2H+ cores analysed with a multilevel study of the APEX and ATCA observations.  相似文献   
69.
Zusammenfassung Diskordanzen sind nicht die einzigen Anzeichen orogener Bewegungen; sie entstehen nur bei Sedimentationsunterbrechung und sind ceteris paribus um so grö\er, je länger die Unterbrechung dauerte. Eine Diskordanz ist kein Anzeichen für das Ende einer Bewegung; diese kann synsedimentär weitergehen. Bei synsedimentärer Bewegung konvergiert Dach und Sohle eines Schichtsto\es gegen das Hoch. Wenigstens in den Tiefs herrscht bei synsedimentärer Orogenese Konkordanz.über die Zurechnung einer Bewegung zur Orogenese oder Epirogenese entscheidet nicht die Dauer oder der Diskordanzwinkel, sondern das entstehende Gefüge. Die Wellenlänge der Faltung steht in umgekehrtem Verhältnis zur Intensität der gebirgsbildenden Kraft.Die Orogenese dauert oft durch geologische Stufen oder Formationen kontinuierlich an. Sie verläuft örtlich ruckweise — Spannungsausgleich in mechanisch inhomogenem Medium. Die Paroxysmen sind weder erdweit noch gleichzeitig.Als Phase möchten wir einen im gro\en einheitlichen orogenen Vorgang bezeichnen ohne Rücksicht auf die mechanisch bedingten zeitweiligen örtlichen Intensitätsunterschiede. Anfang und/oder Ende dieser Phasen ändern sich längs des Orogens.  相似文献   
70.
Ohne Zusammenfassung  相似文献   
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