3.2.6 Thimensart Formation - THM

Authors: Malaise, 1900; emend. Michot, 1954.

Description: Shale and micaceous siltstone and fine sandstone with graptolites (Malaise, 1900); laminated with locally some thin red shale beds (Michot, 1954); olive green shale, micaceous, with compact bedding, lamination or fine oblique stratification.

Stratotype: Right bank of the Fuette river, between the road to Fosses and the old Ferme de Thimensart, east of Fosses (Martin, 1969).

Area: Condroz inlier.

Thickness: Difficult to estimate but in the order of 100 m (Michot, 1957).

Age: The graptolite biozones Monograptus nilssoni, M. scanicus and M. tumescens were recognised, Gorstian, early Ludlow in age (Michot, 1954); the P. nilssoni and the L. scanicus biozones were recognised by Rickards in Maes et al. (1978).

Remarks: Synonyms: Assise de Thimensart, Schistes de Thimensart.

(J. VERNIERS)