Dumbarton Rock
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Condition (NatureScot)
| Unit | Feature | Condition | Area (ha) | Assessed |
|---|---|---|---|---|
| F1 | Carboniferous - Permian Igneous | Unfavourable No Change | — | 2024-08-15 |
Geology & landscape
Geological Period: Carboniferous · Rock Type: Basalt
Landscape processes: Volcanic / Igneous
Description
DUMBARTON ROCK Dumbarton Rock, located south of the town of Dumbarton, is a well-preserved and nationally important example of a volcanic plug of Lower Carboniferous age (around 340 million years ago) composed of hawaiitic basalt. It exhibits well developed columnar jointing forming a pattern which indicates that the plug occupies a cone shaped pipe that narrows downwards. At the margin of the plug hydrothermal chlorite and albite are developed and recent Sr-isotope studies suggest that the margin formed a preferred fluid pathway where an influx of fluids from the country rocks was heated and rose upward along cooling joints.