CRUSHING OF SEDIMENTARY ROCK SAMPLES AND ITS EFFECT ON SHAPE AND NUMBER OF HEAVY MINERALS     

DIERK HENNINGSEN 《Sedimentology》1967,8(3):253-255

Few examples are given to demonstrate that crushing of hard sedimentary rocks practically does not break up the heavy minerals present in the rock. Also the ratios of the various minerals mostly are not changed.  相似文献   

Weichselian glacial history of the Svalbard area: correlating the marine and terrestrial records     

DIERK HEBBELN 《Boreas: An International Journal of Quaternary Research》1992,21(3):295-302

Investigation of eight deep-sea sediment cores from the Fram Strait provides evidence of two phases with an increased input of ice-rafted detritus (IRD) during the last 130,000 years. For the Middle and Late Weichselian events, east-west trends in accumulation rates and terrestrial organic matter content in the deep-sea sediments point to Svalbard as the source area of the IRD. Both phases are clearly correlated with glacier advances on Svalbard, allowing the application of marine stratigraphy to the terrestrial field sections. Since the dating of the terrestrial record of the Weichselian glacial history of Svalbard is still uncertain, this correlation will improve the age assignments to the individual glacial events.  相似文献   

How a river submerges into the sea: a geological record of changing a fluvial to a marine paleoenvironment during early Holocene sea level rise     

D.A. HEPP  O.E. ROMERO  T. M RZ  R. DE POL‐HOLZ  D. HEBBELN 《第四纪科学杂志》2019,34(7):581-592

Coastal seas, and in particular estuarine systems, were significantly affected by Quaternary sea level changes. Furthermore, the dynamics of shelf and coastal evolution have had a strong impact on coastal landscapes inhabited by humans. The postglacial evolution of the vast North Sea shelf with its huge drainage systems, e.g. the Elbe Paleovalley and its tributary system, is an excellent research target to understand how coastal shelf environments change in response to sea level rise. In this study, we investigate infill sediments of the Paleo‐Ems valley – a drowned extension of the modern Ems River and part of the Elbe Paleovalley drainage system. Radiocarbon‐dated transgression sequences provide several new observations regarding the mode and rate of the river system submerging due to the Holocene transgression. Thus, the Paleo‐Ems valley submerged within a short time span of~200 years since the river was not able to adjust its gradient to the rapid rising sea level. The fate of the Paleo‐Ems is exemplary for the rapid change of a former fluvial landscape into a coastal landscape and finally into a submarine seascape. © 2019 The Authors. Journal of Quaternary Science Published by John Wiley & Sons Ltd.  相似文献