Trenching at Rhynie

The Rhynie chert is nowhere exposed naturally at the surface, being found primarily as loose 'float' blocks in the fields. Apart from drilling, the only means available to see the chert and interbedded sediments in situ is to dig trenches. The photograph on the left illustrates one of a series of trenches excavated in August 1963. Here the trench has intersected one of the chert beds (the light coloured rock just above left of center and bottom right) where it is interbedded mainly with dark shales and minor muddy sandstones. The beds are dipping quite steeply to the northeast (right as viewed).

By observing the cherts in situ we can better understand their geometry (e.g. whether they occur as tabular beds or lenses), lateral continuity, and distribution in relation to the sedimentary rocks in which they occur.

Try clicking on the cherts in the picture for a close-up!

1963 trench

Above: Photograph of one of the trenches dug in 1963 showing a chert bed dipping steeply to the northeast (to the right in photograph).

In 1997, trenching to the north-east of the Rhynie chert locality in the vicinity of Windyfield Farm revealed the only known in situ occurrence of the Windyfield chert (see section on Geology and Setting).

More recent trenching, since 2000, in the northern part of the Rhynie Basin away from the Rhynie chert locality has helped to constrain the sedimentary sequence, stratigraphy and structural geology of the area (see Rice et al. 2002; Rice & Ashcroft in press).