Seismic velocities of the upper crust of the Southern Uplands
The Southern Uplands of Scotland is a region largely
composed of deformed Lower Palaeozoic rocks of Ordovician
and Silurian systems. At outcrops, these rocks are mainly
alternating shales and greywackes with steep dips and
regional NE-SW strike which are intruded in places, by
granitic plutons. The Southern Uplands Fault (SUF) which
forms the northern boundary of the region is said to coincide
with the sUbduction zone where a southerly oceanic plate was
being consumed under a continent. Tectonic contrasts north
and south of the SUF have been a subject of intensive
geological and geophysical studies for the past decade.
Field seismic refraction experiments, in particular, have
shed some light about the velocity distribution in the
crust of the Southern Uplands.