Floodplain sediments on the divide between Huang He and Chang Jiang,Gansu Province,NW China

At Lingfeng, (34°17'N, 104°08'E) on the northern slopes of the Qinling Mountains, a stratigraphic survey was made of a 21-m-profile of floodplain sediments on the watershed between the Chang Jiang (Yangtze River) and Huang He (Yellow River) at 2500 m above sea level. The sediments contain <2 m thick layers of peat and detritical plant matter that had been deposited on the floodplain of the Langouhe. If the radiometric dates are reliable, the chronology of the site spans some 80,000 years, covering an accumulation process from the terminal Last Interglacial up to <24 ka BP. The phase >73 ka BP had cool and wet conditions with a coniferous forest vegetation. Between 73 ka and > 40 ka colder and drier conditions were likely. The vegetation changed from aPicea-Pinus forest to aPicea-Abies-Larix forest with a later increase of non-arboreal pollen. Around 40 ka the climate was warm and moist. The accumulation of silt and organic matter as well as the development of a mixed coniferous forest with high rates of thermophilous trees(Quercus, Castanea) characterize the interstadial conditions at this time. Later on, the climate changed to cool and moist conditions, evidenced by silt and peat accumulation and a coniferous forest vegetation up to <24 ka BP. The loess in this area was deposited after 24 ka and erosion by the tributaries of Chang Jiang and Huang He to a depth of at least 40 m created the watershed between the two river systems.     

Influence of source distance and depth on the branches ofPKP waves

Summary The average dependence of the calibration function q and the travel-time residuals t on the depth and distance of the source has been derived for individual branches of PKP waves using earthquakes from the SW Pacific Ocean (distance interval 147°–159°, depths 0–700 km). The analysis of very distant shocks of all depths according to the regional PKP travel time tables can be completed by the magnitude determination.     

Pyroxene glasses — candidates for the interstellar silicate dust component

Experimentelle Arbeiten, die von der Universitäts-Sternwarte Jena in Zusammenarbeit mit chemischen Institutionen durchgeführt wurden, haben gezeigt, daß Pyroxengläser vielversprechende Kandidaten zur Identifizierung von Silikatstaubteilchen in der Umgebung sehr junger Objekte in Molekülwolken, z. B. BN-Objekten und T-Tauri-Sternen, sind. Die Wichtigkeit dieser Experimente besteht darin, daß sie die zur Modellierung der Quellen benötigren optischen Daten liefern und daß sie es ermöglichen, die mineralogische Beschaffenheit des Teilchenmaterials zu verstehen. In dieser Arbeit werden die Schritle, die in der jüngsten Zeit von der Jenaer Staubarbeitsgruppe in beide Richtungen unternommen wurden, beschrieben.