Norber erratics

Last updated

Norber erratic, December 2014 Norber erratic 24Dec2014.jpg
Norber erratic, December 2014

The Norber erratics are one of the finest groups of glacial erratic boulders in Britain. They are found on the southern slopes of Ingleborough, close to the village of Austwick in the Yorkshire Dales. The Ordnance Survey grid reference of the boulder field is SD764698 .

The erratics are classic geomorphological features from the glaciation of northern England. In his chapter on the Pennines, A. E. Trueman wrote: "Particularly well known are the great perched blocks of dark grit which stand on the limestone platform at Norber near Settle." [1]

Many of the Silurian greywacke [2] boulders at the site are perched on pedestals of limestone up to 30cm high. The boulders were probably deposited by melting ice sheets at the end of the last ice age, around 12,000 years ago. The pedestals have developed because the erratic boulders have protected the underlying limestone from solution by rainfall, giving estimates of the rate of lowering of the surrounding limestone pavement of around 25mm per 1000 years. [3] Recent cosmogenic dating suggests that the boulders have been exposed for around 17,900 years. [4]

Related Research Articles

<span class="mw-page-title-main">Yorkshire Dales</span> Upland area of the Pennines in Northern England

The Yorkshire Dales is an upland area of the Pennines in the historic county of Yorkshire, England, most of it in the Yorkshire Dales National Park created in 1954.

<span class="mw-page-title-main">Geology of Great Britain</span> Overview of the geology of Great Britain

The geology of Great Britain is renowned for its diversity. As a result of its eventful geological history, Great Britain shows a rich variety of landscapes across the constituent countries of England, Wales and Scotland. Rocks of almost all geological ages are represented at outcrop, from the Archaean onwards.

<span class="mw-page-title-main">Yorkshire Three Peaks</span> Mountainous peaks in the Yorkshire Dales National Park

The mountains of Whernside, Ingleborough and Pen-y-ghent are collectively known as the Three Peaks. The peaks, which form part of the Pennine range, encircle the head of the valley of the River Ribble in the Yorkshire Dales National Park in the North of England.

<span class="mw-page-title-main">Ingleborough</span> Mountain in the Yorkshire Dales, England

Ingleborough is the second-highest mountain in the Yorkshire Dales, England. It is one of the Yorkshire Three Peaks, and is frequently climbed as part of the Three Peaks walk. A large part of Ingleborough is designated as a Site of Special Scientific Interest and National Nature Reserve and is the home of a new joint project, Wild Ingleborough, with aims to improve the landscape for wildlife and people.

<span class="mw-page-title-main">Glacial erratic</span> Piece of rock that has been moved by a glacier

A glacial erratic is glacially deposited rock differing from the type of rock native to the area in which it rests. Erratics, which take their name from the Latin word errare, are carried by glacial ice, often over distances of hundreds of kilometres. Erratics can range in size from pebbles to large boulders such as Big Rock in Alberta.

<span class="mw-page-title-main">Pendle Hill</span> Hill in Lancashire, England

Pendle Hill is in the east of Lancashire, England, near the towns of Burnley, Nelson, Colne, Brierfield, Clitheroe and Padiham. Its summit is 557 metres (1,827 ft) above mean sea level. It gives its name to the Borough of Pendle. It is an isolated hill in the Pennines, separated from the South Pennines to the east, the Bowland Fells to the northwest, and the West Pennine Moors to the south. It is included in a detached part of the Forest of Bowland Area of Outstanding Natural Beauty.

<span class="mw-page-title-main">North Pennines</span> Range of hills in northern England

The North Pennines is the northernmost section of the Pennine range of hills which runs north–south through northern England. It lies between Carlisle to the west and Darlington to the east. It is bounded to the north by the Tyne Valley and to the south by the Stainmore Gap.

<span class="mw-page-title-main">Teesdale</span> Valley in Northern England

Teesdale is a dale, or valley, in Northern England. The dale is in the River Tees's drainage basin, most water flows stem from or converge into said river, including the Skerne and Leven.

<span class="mw-page-title-main">Cloughmore</span>

<span class="mw-page-title-main">Carboniferous Limestone</span> Limestone deposited during the Dinantian Epoch of the Carboniferous Period

Carboniferous Limestone is a collective term for the succession of limestones occurring widely throughout Great Britain and Ireland that were deposited during the Dinantian Epoch of the Carboniferous Period. These rocks formed between 363 and 325 million years ago. Within England and Wales, the entire limestone succession, which includes subordinate mudstones and some thin sandstones, is known as the Carboniferous Limestone Supergroup.

<span class="mw-page-title-main">Mushroom stones</span>

Mushroom stones, or mushroom rocks, in Ireland are limestone boulders undercut by past weathering regimes. These rocks take the form of solitary sentinels of limestone which still bear the unmistakable marks of long-continued erosion by ice, soil or lapping waves at the edge of lakes which have since vanished or retreated. These stones are sometimes shaped like mushrooms, others have an overhang facing in just one direction, but all are notched and undercut in such a fashion as to suggest prolonged exposure to standing water at some time in the past. The mushroom-shaped stones are produced where the notching forms a fairly even circle around the stone.

<span class="mw-page-title-main">Geology of England</span> Overview of the geology of England

The geology of England is mainly sedimentary. The youngest rocks are in the south east around London, progressing in age in a north westerly direction. The Tees–Exe line marks the division between younger, softer and low-lying rocks in the south east and the generally older and harder rocks of the north and west which give rise to higher relief in those regions. The geology of England is recognisable in the landscape of its counties, the building materials of its towns and its regional extractive industries.

<span class="mw-page-title-main">Geology of Yorkshire</span>

The Geology of Yorkshire in northern England shows a very close relationship between the major topographical areas and the geological period in which their rocks were formed. The rocks of the Pennine chain of hills in the west are of Carboniferous origin whilst those of the central vale are Permo-Triassic. The North York Moors in the north-east of the county are Jurassic in age while the Yorkshire Wolds to the south east are Cretaceous chalk uplands. The plain of Holderness and the Humberhead levels both owe their present form to the Quaternary ice ages. The strata become gradually younger from west to east.

<span class="mw-page-title-main">Boulder Park</span>

Boulder Park National Natural Landmark, of Douglas County, Washington, along with the nearby McNeil Canyon Haystack Rocks and Sims Corner Eskers and Kames natural landmarks, illustrate well-preserved examples of classic Pleistocene ice stagnation landforms that are found in Washington. These landforms include numerous glacial erratics and haystack rocks that occur near and on the Withrow Moraine, which is the terminal moraine of the Okanogan ice lobe.

<span class="mw-page-title-main">Craven Fault System</span> Geological faulting across the Craven District of North Yorkshire, England

The Craven Fault System is the name applied by geologists to the group of crustal faults in the Pennines that form the southern edge of the Askrigg Block and which partly bounds the Craven Basin. Sections of the system's component faults which include the North, Middle and South Craven faults and the Feizor Fault are evident at the surface in the form of degraded faults scarps where Carboniferous Limestone abuts millstone grit. The fault system is approximately coincident with the southwestern edge of the Yorkshire Dales National Park and the northeastern edge of the Bowland Fells.

<span class="mw-page-title-main">Balancing rock</span> Naturally occurring precariously balanced rock

A balancing rock, also called a balanced rock or precarious boulder, is a naturally occurring geological formation featuring a large rock or boulder, sometimes of substantial size, resting on other rocks, bedrock, or on glacial till. Some formations known by this name only appear to be balancing, but are in fact firmly connected to a base rock by a pedestal or stem.

<span class="mw-page-title-main">High Cup Gill</span>

High Cup Gill, almost a geometrically perfect U-shaped chasm, is a valley deeply incised into the Pennine scarp to the northeast of Appleby-in-Westmorland in Cumbria and within the North Pennines AONB in northern England. It is considered to be glacial in origin, ice having over-ridden the area during successive ice ages. To its southeast is Murton Fell and Dufton Fell is to the north.

<span class="mw-page-title-main">Harboro' Rocks</span> Hill in the Derbyshire Peak District

Harboro' Rocks is a dolomitic limestone hill near the village of Brassington in the Derbyshire Peak District. The summit is 379 metres (1,243 ft) above sea level with views across to Carsington Water.

<span class="mw-page-title-main">Crummackdale</span> A valley in North Yorkshire, England

Crummackdale,, is a small valley north of the village of Austwick in the Craven District of North Yorkshire, England. The Valley is drained by Austwick Beck, which flows into the River Wenning, which in turn heads westwards to empty into the Irish Sea. Crummackdale is a narrow south west facing dale, at the south west corner of the Yorkshire Dales National Park.

The geology of the Yorkshire Dales National Park in northern England largely consists of a sequence of sedimentary rocks of Ordovician to Permian age. The core area of the Yorkshire Dales is formed from a layer-cake of limestones, sandstones and mudstones laid down during the Carboniferous period. It is noted for its karst landscape which includes extensive areas of limestone pavement and large numbers of caves including Britain's longest cave network.

References

  1. Trueman, A.E. (1949). Geology and Scenery in England and Wales. Pelican. p. 169.
  2. Edwards, W.; Trotter, F. M. (1954). British Regional Geology: The Pennines and Adjacent Areas. HMSO.
  3. Goudie, A.; Gardner, R. (1992). Discovering Landscape in England and Wales. Chapman and Hall.
  4. Drury, S. (2013). "Update on a classic British field site" . Retrieved 15 October 2021.

54°07′24″N2°21′36″W / 54.1234°N 2.3601°W / 54.1234; -2.3601