Glacial erratic - Wikipedia
A glacial erratic is a 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 ("to wander"), are carried by glacial ice, often over distances of hundreds of kilometres.
Erratic | Glacial Movement, Rock Types & Landforms | Britannica
Erratic, glacier-transported rock fragment that differs from the local bedrock. Erratics may be embedded in till or occur on the ground surface and may range in size from pebbles to huge boulders weighing thousands of tons.
Glossary - Terms E - USGS Publications Warehouse
Erratic. A rock of unspecified shape and size, transported a significant distance from its origin by a glacier or iceberg and deposited by melting of the ice.
More Science – Washington Glacial Erratics - University of …
Erratics may be incorporated into glacial ice by two main processes: (1) large blocks of bedrock, that are susceptible to freeze-thaw weathering, may fall onto a glacier’s surface from bedrock exposures, such as nunataks, cirque headwalls or artetes, or (2) glacial quarrying of the underlying bedrock as the ice flows over a topographic feature t...
Science – Washington Glacial Erratics
What are glacial erratics? During the Last Glaciation (25,000 – 12,500 years ago), as Earth’s climate cooled, major ice sheets developed and expanded world-wide covering large areas of the northern Eurasian and North American continents (Fig. 1).
Intro – Washington Glacial Erratics
Glacial erratics are large pieces of bedrock that have been transported by glaciers or icebergs and deposited in a new location that typically differs from the bedrock source. Erratics can be found overlying bedrock or embedded in till in areas that were previously glaciated.
Glacial Erratics - SpringerLink
A glacial erratic is a glacially transported clast of non-local provenance. Some erratics are noteworthy because of their large size or exotic bedrock type. Erratics were pivotal to the development of the Ice Age theory, popularized by Louis Agassiz.
Glacial Erratics | Iowa Science Phenomena
Glacial erratics are a common occurrence in farm fields of the Iowa Erosional Surface landform (Landforms of Iowa by Jean Prior). These rocks originated in regions to the north and were moved here during the most recent period of glaciation, 10,000-14,000 years ago.
Glacial erratic geology field trips
A glacial ‘erratic’ is a rock fragment carried by glacial ice and transported some distance from the outcrop from which it was derived, and generally resting on bedrock of a different type* [although glacial or alluvial sediment may directly underlie the erratic.
Erratic - Encyclopedia.com
2018年5月21日 · erratic In geology, a rock that has been transported some distance from its source by glacial action, and is therefore of a different type to the surrounding rocks. The tracing of erratics can give important information about the movement of ice.
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