The current case study presents results of the ground-penetrating radar (GPR) profiling at one of the Saadjärve drumlin field interstitial troughs, the Rahivere bog, eastern Estonia. The study was conducted in order to identify the bog morphology, and the thickness and geometry of the peat body. The method was also used to describe the applicability of GPR in the evaluation of the peat deposit reserve as the Rahivere bog belongs among the officially registered peat reserves. Fourteen GPR profiles, ~ 100 m apart and oriented perpendicular to the long axis of the depression, covering the bog and its surrounding areas, were acquired. In order to verify the radar image interpretation as well as to evaluate the velocity of electromagnetic waves in peat, a common source configuration was utilized and thirteen boreholes were drilled on the GPR profiles. A mean value of 0.036 m ns–1 corresponding to relative dielectric permittivity of 69.7 was used for the time–depth conversion. Radar images reveal major reflection from the peat–soil interface up to a depth of about 4 m, whereas drillings showed a maximum thickness of 4.5 m of peat. Minor reflections appear from the upper peat and mineral soil. According to the borehole data, undecomposed peat is underlain by decomposed one, but identifying them by GPR is complicated. Mineral soil consists of glaciolimnic silty sand in the peripheral areas of the trough, overlain by limnic clay in the central part. The calculated peat volumes (1 200 000 m3) were found to exceed the earlier estimation (979 000 m3) that was based solely on drilling data. Ground-penetrating radar, as a method that allows mapping horizontal continuity of the sub-peat interface in a non-destructive way, was found to provide detailed information for evaluating peat depth and extent

The distribution of five groups of fossils in the upper Llandovery (Telychian) and Wenlock of the Viirelaid core section, Estonia, is presented and discussed in terms of their biozones (conodonts and chitinozoans) and mutual positions (scolecodonts, ostracods, and brachiopods). Graphical correlation of the Viirelaid and Paatsalu sections shows a stronger linear correlation for zonal conodonts than for chitinozoans and scolecodonts. In the given case, this is caused by different nature of zones: chitinozoan zones are based on appearances and/or disappearances of ordinal taxa whereas conodont zonation corresponds, as a rule, to evolutionary succeeding species in the Pterospathodus lineage. At the same time, the positions of chitinozoan zones in the Viirelaid, Ruhnu, Aizpute, and Paatsalu cores are oscillating with respect to conodont zones.

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