4.2.2. Tisselt Member v15012016

2.     Tisselt Member

Authors:Bogemans (1988, 1993) informally introduced the Tisselt Member.

Description: Yellow to grey alternated bedded deposits of silty and sandy sediments.

The deposits  consist either of well-defined alternating layers or laminae of silt and sand with very distinct bounding surfaces or as a unit in which one texture predominates interlayered with layers or laminae of different texture. In the coversand area commonly sand predominates whereas in the transitional area silt prevail. 

Massive bedding, horizontal bedding and small ripple bedding is observed. Frost cracks and deformation structures are common (on several levels).

If present, the Tisselt Member is always covered by the Opgrimbie Member. It lays on Quaternary or pré-Quaternary deposits.

Stratotype: Two stratotypes are defined for this member as the textural composition of this unit differs for different depositional areas. The stratotype for the northern part of the sand belt is core 58E296 (Lambert coordinates: x = 151159, y = 191869; z = 7.91 m TAW). The stratotype for the transitional area is core 73W279 (Lambert coordinates: x = 152840, y = 185257; z = 13.5 m TAW).

Area: the coversand and the transitional area.

Thickness: less than a meter to several meters

Age: Weichselian