Editing Geology of the North Tyne and Saughtree - an excursion

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Continue on the road, crossing the border and passing a large double-arch lime kiln on the left. Limestone was worked in shallow quarries on the hillside beyond, but the beds are thin and the overburden increases rapidly into the hillside. After 2.5 km the road emerges from the forest, crosses a stone bridge and a cattle grid. Turn right immediately into a level grassy area by the stream.
 
Continue on the road, crossing the border and passing a large double-arch lime kiln on the left. Limestone was worked in shallow quarries on the hillside beyond, but the beds are thin and the overburden increases rapidly into the hillside. After 2.5 km the road emerges from the forest, crosses a stone bridge and a cattle grid. Turn right immediately into a level grassy area by the stream.
  
==== Locality 11, Caddroun Burn [NY 584 985] ====
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==== Locality 11, Caddroun Burn [NY 584 985] ====
  
The burn flows southeast before it turns sharply to join Liddel Water, and was probably once a tributary of the North Tyne. A small exposure of sandstone dipping downstream, largely under water, at the downstream end of the large circular culvert represents the oldest exposed Carboniferous sediments in the Lower Border Group. Climb over the railway embankment. On its upstream side are exposures of the earliest Carboniferous Birrenswark Lavas below the sandstone. These are '''olivine basalts''', often vesicular especially towards the tops of flows, and usually highly weathered. Continue 250 m upstream of the culvert to a small cliff on the west bank showing 5–6 m of Upper Old Red Sandstone. This exposure is loose and overhanging. Traces of drilling suggest it was quarried, probably for railway construction. The O.R.S. here consists mainly of red and mottled sandstones with subordinate mudstones and sandy shales. There are two horizons of '''calcrete''', one at the base approximately 10 cm thick and another near the top of the succession about 1.1 m thick. The base of the lavas is visible at the top of the exposure and can be inspected safely in a smaller exposure 20 m upstream where it is vesicular and exhibits spheroidal weathering. The lavas appear to be conformable with the O.R.S. and dip downstream at about . If time permits, further good exposures of the O.R.S. can be seen 400 m upstream in the Caddroun Pots, a series of scour holes in the stream bed.
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The burn flows southeast before it turns sharply to join Liddel Water, and was probably once a tributary of the North Tyne. A small exposure of sandstone dipping downstream, largely under water, at the downstream end of the large circular culvert represents the oldest exposed Carboniferous sediments in the Lower Border Group. Climb over the railway embankment. On its upstream side are exposures of the earliest Carboniferous Birrenswark Lavas below the sandstone. These are olivine basalts, often vesicular especially towards the tops of flows, and usually highly weathered. Continue 250 m upstream of the culvert to a small cliff on the west bank showing 5–6 m of Upper Old Red Sandstone. This exposure is loose and overhanging. Traces of drilling suggest it was quarried, probably for railway construction. The O.R.S. here consists mainly of red and mottled sandstones with subordinate mudstones and sandy shales. There are two horizons of calcrete, one at the base approximately 10 cm thick and another near the top of the succession about r.1 m thick. The base of the lavas is visible at the top of the exposure and can be inspected safely in a smaller exposure 20 m upstream where it is vesicular and exhibits spheroidal weathering. The lavas appear to be conformable with the O.R.S. and dip downstream at about 5. If time permits, further good exposures of the O.R.S. can be seen 400 m upstream in the Caddroun Pots, a series of scour holes in the stream bed.
  
 
Rejoin the road. Continue southwest to the second of two prominent rock scars on the left, parking at a lay-by just before a stone wall meets the road at right-angles.
 
Rejoin the road. Continue southwest to the second of two prominent rock scars on the left, parking at a lay-by just before a stone wall meets the road at right-angles.

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