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221.
Hans Stille 《International Journal of Earth Sciences》1917,8(3-4):89-142
Ohne ZusammenfassungVorgetragen auf der Hauptversammlung in Frankfurt a.M. am 6. Jan. 1917. 相似文献
222.
Hans Frebold 《International Journal of Earth Sciences》1931,22(1):29-40
Ohne Zusammenfassung 相似文献
223.
Hans Cloos 《International Journal of Earth Sciences》1929,20(1):66-75
Ohne Zusammenfassung 相似文献
224.
Hans Markgraf 《Pure and Applied Geophysics》1961,49(1):244-248
Zusammenfassung Für 11 ausgewählte Gebiete auf dem Hauptschiffahrtweg längs der nordafrikanischen Küste sind Jahresgänge des Dampfdrucks und der relativen Feuchte aus den Messungen abgeleitet, die seit 1950 an Bord deutscher Handelsschiffe mit dem Schleuderpsychrometer durchgeführt wurden. Eine Erklärung des inversen Ganges der relativen Feuchte auf See wird versucht.
Summary For 11 selected areas within the principal route of navigation along the coast of Northern Africa annual variations of vapour pressure and humidity are derived from measurements with help of swing psychrometers, which were carried out since 1950 aboard German merchant ships. An explanation of the inverse variation of the humidity at sea is attempted.相似文献
225.
Hans VOLKERT 《大气科学进展》2017,34(5):571-575
<正>1.Introduction Spectacular advances have been made in the atmospheric sciences on a global level during a period of one hundred years or more,which is arguably most evident through"the quiet revolution of numerical weather prediction"(Bauer et 相似文献
226.
Kaare L. RASMUSSEN Hans J. F. OLSEN Raymond GWOZDZ Euginev M. KOLESNIKOV 《Meteoritics & planetary science》1999,34(6):891-895
Abstract— We have measured excess Ir and depletion of 14C, two independent indicators of cosmic material, in peat cores from the central Tunguska impact site. Both Ir and 14C show pronounced anomalies in the same stratigraphical depth interval. We have estimated an integral deposition of nonradioactive cosmogenic C of 6.8 ± 1.0 mg C cm?2, and an integrated Ir deposition of 5.9 ± 1.2 pg Ir cm?2. The very high C/Ir ratio and a deduced δ13C value of +55 ± 10% relative to V Pee Dee Belemnite (VPDB) of the impactor material found in this study points towards a cometary type impactor, rather than a chondritic or achondritic asteroidal type impactor. 相似文献
227.
Abstract. Four individual dugongs Dugong dugong , MÜLLER, 1776 were tracked with buoyant, tethered. conventional and satellite radio transmitters. The dugongs three adult females and one immature male were encircled with a net at a catch site near Haruku Island, East Indonesia, and tracked for between 41 and 285 days. The animals showed individualistic patterns of movement, moving between 2 and 3 core areas, travelling between 17 and 65 km from the site of capture. One adult female spent most of the time at two distinct inshore seagrass beds separated by about 17 km; she made five trips between the two sites. Two other females made separate trips to two distinct sites, one of them returning to the catch site at Haruku Island. The immature male journeyed between two areas about 65 km apart. completing the journey in four days. The patterns of movement confirmed a practice of regular recropping of restricted grazing swards by small, loose feeding assemblages rather than fixed herds with a strong social bond. Mean home ranges covered 4.1 km2 50% harmonic mean and 43.4 km2 95% harmonic mean. 相似文献
228.
Central European Cenozoic plume volcanism with OIB characteristics and indications of a lower mantle source 总被引:6,自引:0,他引:6
Average concentrations of incompatible elements and isotopes of radiogenic Sr, Nd and Pb in a 350 km long belt of Central
European volcanics (CECV) resemble those in OIB in general and in OIB from the N Atlantic in particular. This similarity allows
to infer comparable sources for CECV and OIB which might have been located in the lower mantle according to seismic tomography
and chemistry, with the latter unlike a MORB source. The incompatible element contribution of lower mantle origin can be modelled
from primitive mantle minus continental crust and upper mantle inventories. Alkali basaltic magmas from the modelled source
are close in composition to CECV and OIB. The continental crust contains almost half of the silicate Earth's content of Rb,
K, Pb, Ba, Th and U, which were mobilized to a major extent through dehydration of subducted ocean crust. Related losses from
the lower mantle had to be replaced by deep subductions of oceanic lithosphere recognized from their isotopic imprint. From
a balance based on Nd isotopes it can be concluded that average CECV contains 60% matter from residual primitive mantle and
40% from deeply subducted lithosphere (including some young upper mantle materials). Plume products from separate CECV regions
developed, within 45 Ma, from rather depleted to more primitive isotopic signatures. Four periods of volcanism from Eocene
to late Quaternary time are explained as four pulses of an almost stationary ultrafast plume uprise as modelled by Larsen
and Yuen (1997). Magma production has increased from the first to the third pulse with the peak during Miocene time in the
Vogelsberg region. The final pulse produced the Quaternary Eifel volcanoes. Tectonism from the Alpine orogen has probably
triggered the synchronous volcanism of CECV, Massif Central etc. The European lithospheric plate has moved under the control
of the opening Atlantic almost in an eastern direction with a velocity of 1 cm per year and has shifted extinct volcanoes
off their source channels.
Received: 10 July 1998 / Accepted: 10 February 1999 相似文献
229.
230.
Johannes Becherer Jacobus Hofstede Ulf Gräwe Kaveh Purkiani Elisabeth Schulz Hans Burchard 《Ocean Dynamics》2018,68(1):131-151
The impact of sea level rise (SLR) on the future morphological development of the Wadden Sea (North Sea) is investigated by means of extensive process-resolving numerical simulations. A new sediment and morphodynamic module was implemented in the well-established 3D circulation model GETM. A number of different validations are presented, ranging from an idealized 1D channel over a semi-idealized 2D Wadden Sea basin to a fully coupled realistic 40-year hindcast without morphological amplification of the Sylt-Rømøbight, a semi-enclosed subsystem of the Wadden Sea. Based on the results of the hindcast, four distinct future scenarios covering the period 2010–2100 are simulated. While these scenarios differ in the strength of SLR and wind forcing, they also account for an expected increase of tidal range over the coming century. The results of the future projections indicate a transition from a tidal-flat-dominated system toward a lagoon-like system, in which large fractions of the Sylt-Rømøbight will remain permanently covered by water. This has potentially dramatic implications for the unique ecosystem of the Wadden Sea. Although the simulations also predict an increased accumulation of sediment in the back-barrier basin, this accumulation is far too weak to compensate for the rise in mean sea level. 相似文献