Age of the Grampian event: a Discussion of “New evidence that the Lower Cambrian Leny Limestone at Callander, Perthshire, belongs to the Dalradian Supergroup, and a reassessment of the ‘exotic’ status of the Highland Border Complex”

Abstract

As a contribution to the current debate on the age of the Grampian Orogeny in the Scottish Dalradian, we comment on the valuable paper by Tanner (1995) that establishes stratigraphical continuity between the ‘Dalradian’ Ben Ledi Formation and the ‘Highland Border’ Keltie Water Formation that contains the Lower Cambrian Leny Limestone (Cowie, Rushton & Stubblefield, 1972, p. 17). Tanner's interpretation of the stratigraphy differs in detail from that of Harris & Fettes (1972). We unreservedly accept Tanner's mapping and the stratigraphical changes that follow from it: there are two units of black slate and limestone; that containing the fossiliferous limestone of Leny Old Quarry is the younger.