rock types and landscapes
DESCRIPTION
Rock types and the landscapes they can create. For Leaving Certificate Geography (Ireland)TRANSCRIPT
Rock Types and Landscapes
¼ of the world’s population live in Karst areas (most of this ¼ is found in China)
Formed by Chemical weathering (from rainwater) and erosion
Limestone – Karst Areas – P 92
2010 Ordinary Level Leaving Cert
Burren – a Karst area
Aran Islands – A Karst Area
Sligo, Leitrim, Fermanagh
Mammoth Caves, Kentucky
Northern Slovenia
Thailand/China – Tower Karst….
…..as seen in Avatar
Lack of rivers/lakes Presence of Swallow Holes – where water disappears
underground Presence of hollows – dolines Presence of underground water (in caves)
Characteristics of Karst Landscapes
Limestone is permeable (water can pass through) Well jointed (vertical “gaps”) Has bedding planes (horizontal “gaps” between layers) Easily chemically weathered
Formation of Karst
Surface Features - Pavement
Clints and Grikes (Gaps)
A Swallow Hole – where a river disappears underground
Dolines – collapsed caverns
Turlough – Disappearing lakes
Turlough – Disappearing lakes
Underground Features - Caves
Undeground Features - Caves
Many cave features are formed by Deposition Rainwater (slightly acidic from the CO2 in the air) dissolves
Calcium Carbonate in Limestone. The dissolved Calcium Carbonate (called Calcite) is deposited
in caves
Cave Features
Stalactites – hang on “tite”
Stalagmites, Pillars/Columns
2009 Leaving Cert OL
Important source of water – many springs in Limestone areas.
Ballygowan water – from limestone area in Limerick
Karst Landscapes - Value
Very important for tourism◦ Caves are tourist attractions (e.g. Ailwee Cave)◦ Unique landscape◦ Planning restrictions mean landscape is kept unspoilt – no
housing estates/McDonalds/Shopping centres allowed◦ Historic features
Karst Landscapes - Value
Unique Ecosystem…. Unusual plants and animals
Karst Landscapes - Value
Engineering difficulties◦ Caves may collapse◦ Industrial Development Restricted ◦ Problems with fresh water contamination due to permeable
nature of landscape – fertiliser, sewerage etc can easily contaminate drinking water supplies
◦ Agricultural development restricted – farming is difficult
Karst Landscapes – Problems
2006 Ordinary Level Question
2008 Higher Level Question