Previous SiteNext Site

Montiaghroe Townland QuarryFermanagh
PHOTO TO BE ADDED Quarry in Montiaghroen Townland, Co. Fermanagh.
Summary Full report
Site Type: Quarry (disused)
Site Status: PASSI
District: Fermanagh District Council
Grid Reference: H18966892
Rocks
Rock Age: Carboniferous (Arundian, Visean)
Rock Name: Drumskinny Sandstone Member, Mullaghmore Sandstone, Tyrone Group
Rock Type: Sand, Sandstone
Interest
Fossil Groups: Bivalve, Brachiopod, Crinoid, Polyzoan, Trace fossil
Other interest: cross-bedding, ripple marks, Marine sediments

Summary of site:

All named sedimentary rock formations are defined from a single locality where all the important aspects of the formation can be seen. Ideally the base should also be defined. Such localities are the type localities or stratotypes of the formations named. This account describes the stratotype of the Drumskinny Sandstone Member which is part of the Mullaghmore Sandstone Formation of the Lower Carboniferous. It was formed about 342 million years ago.

In this small, abandoned quarry, on a face 10 m long, white to pale brown sandstones about 2 m thick can be seen. They are in thin beds inclined 10 degrees to the south. They are formed from pure quartz sands with the odd fleck of mica and were obviously colonised by two animals that either lived in or fed on sediments (or both). One burrow form, called Arenicolites, is similar in form to modern marine worm burrows, the other, called Rhizocorallium, is a u shaped tube either oblique to or parallel with the bedding plane and has no modern analogue. There is no trace of the animals that created them. Brachiopods are very sparsely distributed in the member which shows ripple marks and cross-laminations and, at other localities, channels and erosion surfaces. This member was deposited in a marine environment and this locality was obviously a shallow, sandy sea bed vigorously winnowed by waves and currents able to wash finer clay and mud particles away. At other localities it contains more lime and a rich sea floor fauna washed in during stormy conditions. In all places where it occurs it is obviously deltaic. Stratotypes, by definition, are the key reference localities for their formations and should therefore be preserved for all future comparisons.


Previous SiteNext Site

|Home|