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Geomorphic Features Associated with Erosion
Published in Ramesh P. Singh, Darius Bartlett, Natural Hazards, 2018
Niki Evelpidou, Isidoros Kampolis, Anna Karkani
This comprises a landform shaped like a bowl, which is actually the starting point of a glacier. In glacial environments, the cirque belongs to the more elevated formations, along with the aretes and horns. The three sides of this depression have escarped walls, and the fourth side is open and descends into the glacial valley comprising the starting point of the glacier. The cirque, before its depression, is a simple irregularity on the side of the mountain, which is later augmented in size as it becomes more and more full of ice. When the glacier starts to heave towards lower altitudes, the open side of the cirque is widened. After the glacier melts, these depressions are usually occupied by small mountain lakes called tarns.
Fish stocking for recreational angling is culpable for the poor condition of many English lakes designated for conservation purposes
Published in Inland Waters, 2022
Eleanor R. Skeate, Martin R. Perrow, Mark L. Tomlinson, Genevieve Madgwick, Andrew J. P. Harwood, David Ottewell, Richard Berridge, Ian J. Winfield
The resultant contemporary species inventory was compared with that thought likely to comprise the natural fish assemblage of the lake given its geographic location, the broad nature of the wider catchment, connectivity to surrounding streams/rivers, and habitat preferences and distribution of the fish species in the UK (Davies et al. 2004). For example, a fish community typical of a eutrophic shallow lowland lake would not be appropriate for an upland oligotrophic tarn. Species only naturally present in the lower, slower-flowing reaches of rivers, such as bream, would not typically colonise lakes fed only by headwater streams, although species such as European eel (Anguilla anguilla, hereafter eel), pike, and European perch (Perca fluviatilis, hereafter perch) may be expected.
Geoheritage values of consanguineous wetland suites on the Swan Coastal Plain, Western Australia
Published in Australian Journal of Earth Sciences, 2019
For the purposes of this paper, the selected wetland definition is a broad one (C. A. Semeniuk, 1987; Wetlands Advisory Committee, 1977): areas of permanently, seasonally, intermittentlyortidally waterlogged to inundated soils, sedimentsorland, whether natural or artificial, fresh to saline. Without digressing to discussing how wetlands become wet, or the extent, nature, or permanence of wetting, and leaving aside the nature of the processes involved in development of their sediments and soils, and their chemical and biological diversity, the subject of this paper is simply ‘wet land’ (two words) in its myriad expressions. Wet land includes all the common terms used to refer to these features, such as floodplain, river, creek, wadi, playa, pan, sabkha, arroyo, lake, salt lake, pond, slack, seep, spring, fen, bog, mire, moor, oasis, marsh, bottomland, swamp, tarn, estuary, mangrove swamp, tidal flat, among others. It includes ecosystems, which are markedly, even if intermittently, affected by the presence of water, and excludes ecosystems that are not part of the land (e.g. subterranean caves and shallow marine environments).
Lithostratigraphy of Paleozoic metasediments in southern Fiordland, New Zealand
Published in New Zealand Journal of Geology and Geophysics, 2023
Richard Jongens, Ian M. Turnbull, Andrew H. Allibone
A highly variable succession of biotite, calcic and quartzose psammite, pelitic schist, marble, and quartzite in the Dark Cloud Range (Figure 4E), conformably overlying Long Sound Calc-silicate (Powell 2006), is here named the Prong Lake Formation. This is the structurally uppermost Cameron Group unit preserved. The name Prong Lake Formation replaces the informal Chankly Bore Formation used by Powell (2001, 2006), derived from an informal name for hills west of the lower Long Burn. The type section suggested by Powell (2006) begins near the contact with Long Sound Calc-silicate at the outlet of a tarn at 1128880E 4904120N, and follows a cirque headwall anticlockwise to spot height 1246, southeast of Prong Lake at 1127850E 4904730N (structural top).