::''This the Irish'' Munster Basin ''should not be confused with the'' Münster Basin ''in northern Germany'' The Munster Basin is a late Middle to Upper Devonian age extensional (rift) sedimentary basin in the south-west of

Ireland Ireland ( ; ga, Éire ; Ulster Scots dialect, Ulster-Scots: ) is an island in the Atlantic Ocean, North Atlantic Ocean, in Northwestern Europe, north-western Europe. It is separated from Great Britain to its east by the North Channel (Grea ...

. The basin fill comprises fluvial

Old Red Sandstone The Old Red Sandstone is an assemblage of rocks in the North Atlantic region largely of Devonian age. It extends in the east across Great Britain, Ireland and Norway, and in the west along the northeastern seaboard of North America. It also exte ...

(ORS) magnafaciesWilliams, E.A., Bamford, M.L.F., Cooper, M.A., Edwards, H.E., Ford, M., Grant, G.G., MacCarthy, I.A.J., McAfee, A.M. & O'Sullivan, M.J. (1989) Tectonic controls and sedimentary response in the Devonian-Carboniferous Munster and South Munster Basins, south-west Ireland. In: Arthurton, R.S., Gutteridge, P. & Nolan, S.C. (eds) The Role of Tectonics in Devonian and Carboniferous Sedimentation in the British Isles. Occasional Publications of the Yorkshire Geological Society, 6, 123-141. with minor

silicic Silicic is an adjective to describe magma or igneous rock rich in silica. The amount of silica that constitutes a silicic rock is usually defined as at least 63 percent. Granite and rhyolite are the most common silicic rocks. Silicic is the grou ...

volcanic and

mafic A mafic mineral or rock is a silicate mineral or igneous rock rich in magnesium and iron. Most mafic minerals are dark in color, and common rock-forming mafic minerals include olivine, pyroxene, amphibole, and biotite. Common mafic rocks incl ...

sub-volcanic centres. The depocentre of the basin is located between the

MacGillycuddy's Reeks , photo=MacGuillycuddy's Reeks.jpg , photo_caption= , country=Ireland , country1= , location = County Kerry , region = Munster , region_type = Provinces of Ireland , parent= , border= , length_km=19 , length_orientation=East–West ...

and the Kenmare River on the

Iveragh peninsula The Iveragh Peninsula () is located in County Kerry in Ireland. It is the largest peninsula in southwestern Ireland. A mountain range, the MacGillycuddy's Reeks, lies in the centre of the peninsula. Carrauntoohil, its highest mountain, is als ...

where the succession is at least ''ca''. 6 km thick. The non-marine ORS is conformably succeeded by latest Devonian coastal plain and shallow marine clastic deposits (the Toe Head Sandstone and Old Head Sandstone Formations, and equivalents), followed by shallow to deeper marine Carboniferous sandstones, mudstones and limestones of the South Munster Basin. During the Late Palaeozoic Variscan (or Hercynian) orogeny the deposits in the basin were subjected to compressional deformation that resulted in pressure solution cleavage formation, buckle folding and contractional faulting under very low-grade

metamorphic Metamorphic rocks arise from the transformation of existing rock to new types of rock in a process called metamorphism. The original rock (protolith) is subjected to temperatures greater than and, often, elevated pressure of or more, causi ...

conditions. The oldest deposits found in the Munster Basin belong to the Valentia Slate Formation from which a silicic air-fall

tuff Tuff is a type of rock made of volcanic ash ejected from a vent during a volcanic eruption. Following ejection and deposition, the ash is lithified into a solid rock. Rock that contains greater than 75% ash is considered tuff, while rock ...

bed (the Keel-Enagh Tuff) was radiometrically dated as 384.9 ± 0.7 Ma, which can be linked to local miospore biostratigraphic records. In combination, this corresponds to a late

Givetian The Givetian is one of two faunal stages in the Middle Devonian Period. It lasted from million years ago to million years ago. It was preceded by the Eifelian Stage and followed by the Frasnian The Frasnian is one of two faunal stages in the ...

chronostratigraphic age on recent Devonian time scales. The general Late Devonian age of the basin fill is also given by miospore and fish fossil records.Russell, K. J. (1978) Vertebrate fossils from the Iveragh Peninsula and the age of the Old Red Sandstone. Journal of Earth Sciences, Royal Dublin Society, 1, 151-162.

References

{{Reflist Geology of Ireland