In recent years, the sediments filling Pleistocene glacial structures have become of increasing importance to paleoclimate research. Climatic changes are documented by the deposition cycles in small, closed, trough or bowl-like structures. A 2-D, high-resolution, shallow reflection seismic survey was conducted in 1996 over such a structure near Tostedt in northern Germany. The objective was to obtain a more accurate picture of the structure and the underlying geology. Designed especially for shallow surveys, a newly developed impulse source provided sufficient energy to observe reflectors as deep as 400 m. Signals are characterized by a high-frequency content with maximum energy between 80 and 180 Hz. The migrated section shows a distinct reflection pattern revealing local glacial dynamics. Reflectors at depths of 30, 40, and 45 m from inside the Tostedt structure correlate well with three interstadials of the Weichselian period. Weak reflections define the bottom of the structure, with a maximum depth of 70 m. The structure is imbedded in a much larger, previously unexpected depression of similar shape. The fill of this larger depression is seismically nearly transparent. High-amplitude reflections delineate its lower boundary with a maximum depth of 130 m. Two major reflectors at depths of 170 and 270 m correlate with lower Miocene and middle Oligocene units. They indicate that subrosion, which might have been expected from the presence of a nearby salt diapir, is absent. This confirms the purely glacial origin of the two bowl-like structures.

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