Longyester

Significance: a long-established gravel pit which provides sections in kame and kettle terrain and partially in-filled meltwater channels

glacial stratigraphy  ice age events     streetmap                                                                                                     

The gravel pits near Longyester have been active since at least the early 1970s. The quarries provide the best sections in the stratigraphy of the infilled meltwater channels than run along the south-western flanks of the Lammermuir Hills.

The glacial stratigraphy has been described briefly in BGS reports. A lower till close to the channel floor is overlain by a thick sequence of gravel and sand which forms kames and kame terraces and which is capped by a second till. The cross bedding in the gravels at the eastern end of the channel system, shown below, indicates that a delta was extended into the open mouth of this channel. The till capping shows that there was a final push forward of the ice margin across the kames and kame terraces.

The surface topography was mapped by Sissons and shows fine examples of kames, kame terraces and kettle holes formed when margin of the last ice sheet abutted the Hills. The kames are large features, with broad, gently-rounded or almost flat tops. The kettle holes are also large in scale, with hollows 300 m long and more than 100 m wide. Newey has analysed pollen from borings in the kettle holes for pollen. The oldest peat goes back to the start of the Holocene.