Sediment Input into the Heidelberg Basin as determined from Downhole Logs

Sabine Hunze,Thomas Wonik

doi:10.3285/eg.57.3-4.5

Abstract

Abstract. The Upper Rhine Graben, and the Heidelberg Basin in particular, play an important role in the investigation of climate change and tectonic activity during the Tertiary and Quaternary periods. Several research boreholes were recently drilled to acquire data for a new interpretation of the geology of the northern Upper Rhine Graben. This paper investigates in detail the boreholes at Heidelberg, Viernheim and Ludwigshafen-Parkinsel, as well as the shallower boreholes at Pfungstadt, Stadtwerke Viernheim and Hüttenfeld, in terms of their geophysical parameters. The physical properties of the lithologies described in the cores are characterised on the basis of borehole logging data. A hole-to-hole correlation between adjacent boreholes is then conducted, using the characteristic changes in the ‘natural radioactivity’ parameter to acquire information on changes in sediment provenance (Rhine, Neckar, Pfälzerwald and Odenwald). An interpretation applying the statistical method of cluster analysis allows identifi cation of sections with homogenous physical properties from downhole measurements and thus the determination of possible sediment provenance.

Highlights

One of Europe’s largest river systems, the River Rhine, provides a unique geoscientific data set with the potential of bridging the gap between glaciated alpine areas and the inland ice-sheet advances of Northern Europe (WESTERHOFF 2008)
In the gamma ray logs (GR) vs. density crossplot the coarser-grained sediments are characterised by both low and high density values and the finer-grained ones by high density values. This suggests that the high density values in fine-grained sediments may be caused by mineralogy and/or a higher degree of compaction
In the GR vs. density crossplot, the coarser-grained sediments are characterised by both low and high density values and the finer-grained sediments by high density values

Summary

Introduction

One of Europe’s largest river systems, the River Rhine, provides a unique geoscientific data set with the potential of bridging the gap between glaciated alpine areas and the inland ice-sheet advances of Northern Europe (WESTERHOFF 2008). The Upper Rhine Graben extends approximately 300 km from Basel (Switzerland) to Frankfurt (Germany) and is 35-45 km wide on average This graben is a north-northeasttrending rift of Tertiary age (ELLWANGER et al 2005). During the Quaternary, the subsiding part of the northern Upper Rhine Graben acted as a distal and final accommodation space for coarser alpine material (ELLWANGER et al 2005). The most distal signals of alpine climate dynamics associated with the major events of alpine glaciation can still be identified as sediment bodies within the Pleistocene succession. They are embedded in relatively fine alpine material and coarser local material. In the northern part of the Upper Rhine Graben the graben sediments are generally finer grained, better sorted and mixed with local sediment input from the graben margins (HAGEDORN & BOENIGK 2008)

Methods

Results

Conclusion