Stack (geology)


Stack (geology)

A stack is a geological landform consisting of a steep and often vertical column or columns of rock in the sea near a coast. Stacks are formed when part of a headland is eroded by hydraulic action, which is the force of the sea or water crashing against the rock. The force of the water weakens cracks in the headland, causing them to later collapse, forming a stacks and small island. They also form when a natural arch collapses due to sub-aerial processes and gravity. A stack may collapse or be eroded leaving a stump. Stacks typically form in horizontally bedded sedimentary rocks particularly on limestone cliffs, because of the medium resistance to erosion. Cliffs with weaker rock such as clay tend to slump and erode too quickly to form stacks, while harder rocks such as granite erode in different ways. The sea attacks small cracks and opens them. The cracks then gradually get larger and turn into a small cave. When the cave wears right through the headland, an arch forms. Further erosion causes the arch to collapse. This causes a pillar of hard rock standing away from the coast. This is called a stack.

Stacks are often important sites for nesting seabirds.

Some stacks are famous for rock climbing.

Examples

* Flowerpot Island, Lake Huron, Canada.
* Three Sisters, Eatonville, Nova Scotia.
* Haystack Rock, Cannon Beach, Oregon, USA.
* Goat Rock, California, USA.
* Old Harry Rocks, Dorset, England.
* The Needles, Isle of Wight, England.
* Am Buachaille, Sutherland, Scotland.
* Old Man of Hoy, Orkney, Scotland.
* The Twelve Apostles, Victoria on the Great Ocean Road, Victoria, Australia
* Percé Rock, Percé Quebec, Canada
* Hopewell Rocks, Hopewell Cape New Brunswick, Canada
* [http://images.google.com/images?q=%E7%A0%B4%E9%82%8A%E6%B4%B2&hl=en Po Pin Chau] , High Island, Hong Kong
* Étretat, Seine-Maritime, France
*


Wikimedia Foundation. 2010.

Look at other dictionaries:

  • Stack (geologie) — Stack (géologie) Pour les articles homonymes, voir Stack. Les Douze apôtres sur la côte de l État de Victoria …   Wikipédia en Français

  • Stack (geomorfología) — Old Man of Hoy, Escocia …   Wikipedia Español

  • Stack — Computing*Stack (data structure), a data structure based on Last In, First Out (LIFO) *Call stack of a program, also known as a function stack, execution stack, control stack, or simply the stack *Protocol stack, a particular software… …   Wikipedia

  • Stack (géologie) — Pour les articles homonymes, voir Stack. Les Douze apôtres sur la côte de l État de Victoria en Australie. Un stack est u …   Wikipédia en Français

  • Geology of the Iberian Peninsula — The geology of the Iberian Peninsula consists of the study of the rock formations on the Iberian Peninsula, which includes Spain, Portugal, Andorra, and Gibraltar. The peninsula contains rocks from every age from Ediacaran to Recent, and almost… …   Wikipedia

  • geology — /jee ol euh jee/, n., pl. geologies. 1. the science that deals with the dynamics and physical history of the earth, the rocks of which it is composed, and the physical, chemical, and biological changes that the earth has undergone or is… …   Universalium

  • stack — /stæk / (say stak) noun 1. a large, usually circular or rectangular pile of hay, straw, or the like. 2. any more or less orderly pile or heap. 3. a number of chimneys or flues grouped together. 4. a single chimney or funnel for smoke, or a… …   Australian English dictionary

  • Geology of the Alps — The Alps form a part of a Tertiary orogenic belt of mountain chains, called the Alpide belt, that stretches through southern Europe and Asia from the Atlantic all the way to the Himalayas. This belt of mountain chains was formed during the Alpine …   Wikipedia

  • Fold (geology) — For other uses, see Fold (disambiguation). Very tight folds. Formation near Moruya, New South Wales, Australia …   Wikipedia

  • Glossary of geology terms — Here is a glossary of Geological terms.A*Abyssal plain Flat or very gently sloping areas of the deep ocean basin floor. *Absolute dating the process of determining a specific date (in years or some other unit of time) for an archaeological,… …   Wikipedia


Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”

We are using cookies for the best presentation of our site. Continuing to use this site, you agree with this.