Premium
Late Quaternary depositional history of the Reuss delta, Switzerland: constraints from high‐resolution seismic reflection and georadar surveys
Author(s) -
Nitsche Frank O.,
Green Alan G.,
Horstmeyer Heinrich,
Büker Frank
Publication year - 2002
Publication title -
journal of quaternary science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.142
H-Index - 94
eISSN - 1099-1417
pISSN - 0267-8179
DOI - 10.1002/jqs.645
Subject(s) - geology , fluvial , delta , bedrock , ground penetrating radar , sedimentary depositional environment , geomorphology , quaternary , glacial period , erosion , infill , silt , paleontology , borehole , deposition (geology) , sediment , telecommunications , radar , ecology , structural basin , aerospace engineering , computer science , engineering , biology
Glacial erosion has caused overdeepening of many alpine valleys. After retreat of the ice, they were filled with heterogeneous deposits of glacial, lacustrine and fluvial sediments. A typical example of such a valley segment and its infill is the Reuss delta on the southern shore of Lake Lucerne in Switzerland. To obtain a detailed three‐dimensional image of this valley segment, the ETH Institute of Geophysics has acquired several two‐dimensional, high‐resolution seismic and georadar profiles, and conducted a three‐dimensional georadar survey. Interpretations of these geophysical data were constrained by a geological core extracted from a borehole 300 m deep near the investigation site. The seismic profiles imaged ca. 600 m of sediment infill above bedrock. Based on their reflection characteristics, five different deposition units were distinguished. These units were interpreted as a succession of clay/silt at the base, followed by different sand units with variable but generally increasing amounts of gravel. This succession represented a prograding delta that filled the southern part of Lake Lucerne. The latest fluvial development of the region is best represented by the georadar data. In particular, the three‐dimensional georadar data set provides a detailed view of an ancient braided river channel Copyright © 2002 John Wiley & Sons, Ltd.