Siccar Point is a rocky promontory in the county of

Berwickshire Berwickshire (; ) is a historic county, registration county and lieutenancy area in south-eastern Scotland, on the English border. The county takes its name from Berwick-upon-Tweed, its original county town, which was part of Scotland at the ...

on the east coast of

Scotland Scotland is a Countries of the United Kingdom, country that is part of the United Kingdom. It contains nearly one-third of the United Kingdom's land area, consisting of the northern part of the island of Great Britain and more than 790 adjac ...

. It is famous in the history of

geology Geology (). is a branch of natural science concerned with the Earth and other astronomical objects, the rocks of which they are composed, and the processes by which they change over time. Modern geology significantly overlaps all other Earth ...

for

Hutton's Unconformity Hutton's Unconformity is a name given to various notable geological sites in Scotland identified by the 18th-century Scottish geologist James Hutton as places where the junction between two types of rock formations can be seen. This geological phe ...

found in 1788, which

James Hutton James Hutton (; 3 June Old Style and New Style dates, O.S. 1726 – 26 March 1797) was a Scottish geologist, Agricultural science, agriculturalist, chemist, chemical manufacturer, Natural history, naturalist and physician. Often referred to a ...

regarded as conclusive proof of his uniformitarian theory of geological development.

History

Siccar Point was the site of a dun, or small

hill fort A hillfort is a type of fortification, fortified refuge or defended settlement located to exploit a rise in elevation for defensive advantage. They are typical of the late Bronze Age Europe, European Bronze Age and Iron Age Europe, Iron Age. So ...

, in the territory of the ancient Britons. Siccar Point is now in the parish of

Cockburnspath Cockburnspath ( ) is a village in Berwickshire in the Scottish Borders. It lies near the North Sea coast between Berwick-upon-Tweed and Dunbar. Cockburnspath is the eastern terminus of the Southern Upland Way as well as the northern terminus of ...

but was formerly in the parish of Old Cambus, from which the ancient parish church of St Helen's Chapel survives as a ruin about one kilometre to the west of the point. The church is built in a Romanesque style, in a mixture of Old Red Sandstone believed to have been quarried from the nearby Greenheugh Bay and of the

greywacke Greywacke or graywacke ( ) is a variety of sandstone generally characterized by its hardness (6–7 on Mohs scale), dark color, and Sorting (sediment), poorly sorted angular grains of quartz, feldspar, and small rock fragments or sand-size Lith ...

rock also used in the drystone dyke forming the field boundaries. It is likely that the

medieval In the history of Europe, the Middle Ages or medieval period lasted approximately from the 5th to the late 15th centuries, similarly to the post-classical period of World history (field), global history. It began with the fall of the West ...

village of Old Cambus was nearer to Siccar Point than the extant hamlet of Old Cambus. To the south of the point twentieth-century

quarry A quarry is a type of open-pit mining, open-pit mine in which dimension stone, rock (geology), rock, construction aggregate, riprap, sand, gravel, or slate is excavated from the ground. The operation of quarries is regulated in some juri ...

ing for

to be used as roadstone left a hollow named Old Cambus Quarry which is now occupied by a vegetable distribution warehouse complex.

Hutton's Unconformity

Siccar Point is notable in the history of

as a result of a boat trip in 1788 in which geologist

observed the

angular unconformity An unconformity is a buried erosional or non-depositional surface separating two rock masses or strata of different ages, indicating that sediment deposition was not continuous. In general, the older layer was exposed to erosion for an interval ...

of the point. He wrote later that the evidence of the rocks provided conclusive proof of the uniformitarian theory of geological development; that is, that the natural laws and processes which operate in the universe have never changed and apply everywhere. In respect for its great importance to the development of geoscience, this locality was included by the

International Union of Geological Sciences The International Union of Geological Sciences (IUGS) is an international non-governmental organization devoted to global cooperation in the field of geology. As of 2023, it represents more than 1 million geoscientists around the world. About Fo ...

(IUGS) as the first of 100 global geological heritage sites in a list first published in October 2022. At the location, near vertical marine sandstones of early Silurian (Llandovery) age (c.440 Ma) are overlain unconformably by gently dipping terrestrial sandstones of late Devonian age (c.375 Ma). The intervening 65 million years represent a time between the tectonic closing of an ocean (the Iapetus Ocean) that had existed between Scotland and England and the building of mountains of a Himalayan scale to the north west. The Silurian sediments were first buried, then lithified into rock, then folded and uplifted and finally eroded to a horizontal surface before being buried by Devonian sediments washed south from the erosion of the mountains. Further tectonic movements later tilted the whole to its current gentle northward dip. Hutton's unconformity at Siccar Point, Scotland.jpg, The rugged point, seen from above, shows gently sloping beds of red sandstone above vertical beds of

, forming a classic example of

. Siccar Point red capstone closeup.jpg, The eroded sandstone outcrop above conglomerate and vertical ribs of greywacke, still much as when sketched in 1788 by Hutton's companion Sir James Hall. Huttons Unconformity at Sicar Point by James Hall (1788).jpg, Field sketch of Hutton's Unconformity at Siccar Point, Scotland by Sir James Hall (1788). Headlands south of-Siccar Point.jpg, Headlands south of Siccar Point showing tilted strata and unconformities

References

External links

John Playfair's historic remarks upon seeing Siccar Point
in vol. V, pt. III, 1805, ''Transactions of the

Royal Society of Edinburgh The Royal Society of Edinburgh (RSE) is Scotland's national academy of science and letters. It is a registered charity that operates on a wholly independent and non-partisan basis and provides public benefit throughout Scotland. It was establis ...

''.
Research Casting International hung on scaffolding off the cliffs at Siccar Pointpainting a large section of the rocks with thick liquid latex (photo)to fabricate an exhibit for the Gottesman Hall of Planet Earth

American Museum of Natural History The American Museum of Natural History (AMNH) is a natural history museum on the Upper West Side of Manhattan in New York City. Located in Theodore Roosevelt Park, across the street from Central Park, the museum complex comprises 21 interconn ...

. *
VFE: Siccar Point, Scotland
— virtual excursion in ''Historical Geology'' (A free online textbook for Historical Geology courses) {{Authority control Sites of Special Scientific Interest in Berwickshire and Roxburgh Geology of Scotland Historical geology Protected areas in the Scottish Borders Landforms of the Scottish Borders Headlands of Scotland First 100 IUGS Geological Heritage Sites

History

Hutton's Unconformity

See also

References

External links