|
|
|
| |
|
|
13th April 2006
|
|
|
|
NORTH BERWICK
|
|
|
|
Tour:
Geo
Participants: 12
|
|
|
|
Weather: cool,
sunny, breezy |
|
|
|
|
|
|
Summary
of Geology::
|
Extensive volcanicity
took place in Carboniferous times (ca. 350 Ma) in the North Berwick
district, with numerous deeply eroded vents to be found east of the
town including Partan Craig and the Horseshoe vent. Sheets
of lava and ash make up the Garleton Hills and are well displayed on
the coast further north.
Considerable thicknesses of poorly sorted
volcanic ash, containing large lumps of sedimentary material ripped
from the sides of the volcanoes,
were deposited after
each eruption, to be followed by sheets of low viscosity basalt lava. |
|
 |
The Scottish Seabird Centre rests on a carboniferous lava flow, about
4 metres thick. Below is volcanic ash, here red in colour, but
green in colour further to the east. |
|
|
|
|
 |
Green
volcanic
ash, poorly sorted, with sedimentary material showing layering. |
|
|
|
|
 |
The
Partan
Craig vent; basalt and agglomerate. After cooling, the central
part shrank and collapsed. |
|
|
|
|
 |
Bass
Rock
- a carboniferous intrusion. |
|
|
|
|
 |
North Berwick Law.
A
volcanic plug filled with basalt and agglomerate. Recent glacial
erosion has left the tail at left, indicating ice movement
in that direction - i.e. towards the
east. |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
