Fossils

Tree Ferns, today, New Zealand

Tree Ferns growning in New Zealnd, today, Cyathea species

Tree Ferns, today, New Zealand

Tree Ferns, today, New Zealand

Tree Ferns growning in New Zealnd, today, Cyathea species

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Fossils are the remains of plants, animals and other organisms that have been preserved as impressions on sedimentary rocks.

These fossil remains tell researchers a lot about what the world was once like. Most fossils are found in rocks composed of layers of sediments that settled in ancient oceans, lakes, and rivers (called sedimentary rocks). The older sedimentary rocks are found at the bottom of these layered sequences with younger layers at the top.

Researchers known as palaeontologists study fossils. The fossils in rock layers near the top inform palaentologists about life in the recent past, and those in the lower layers of the sedimentary rock inform them about the more remote past. When they compare fossils to animals that are alive today, they can often see similarities that help identify the relationships between them.

Fossils in Castlecomer

Fern Fossil

A large collection of fossils were found in the Castlecomer mining area. These fossils can be seen today at the London Museum of Natural History.

In William Tighe's Statistical Survey of Kilkenny published in 1801 he states:

"The coal-sill when brought up is full of shining impressions, these are best seen in a fresh fracture."

An acquaintance of Tighe from Wildfield in the parish of Mucullee, Mr. Henry Ellis, stated:

"The stones which bear these impressions, are hard compact pieces of a siliceous rock: they exhibit the figure of the stems of plants, and the joints and often the interior pith, they are indubitably the impressions of exotics produced in southern climes; they appear to have been lodged when soft in the bowels of the earth, at the time of some violent convulsion, probably the universal deluge, when these parts of broken plants floated on the waters and were transported to this country."

Some of the Castlecomer fossils were named after well known people in the area at that time. For example; Wandesforde - Urocordylus Wandesfordii; Bradley - Ichtyerpeton Bradleyae; Edge - Anthracosaurus Edge; Dobbs - Lepterpeton Dobsii.

Fern Fossils

Fern fossils are quite common in shale deposits at opencast mines. The fern groups of plants have fossil records extending back to 350 - 400 million years ago. Ferns have leaves, called fronds. They live in a wide range of habitats, ranging from the tropics to cold temperate regions. This plant was characterized by large fronds with toothed leaflets. Large Tree Ferns were major components of coal-forming forests. Most of these broke up before fossilization and only toothed fragments survived.

Club Mosses

Club Mosses were discovered at greater depth in the mines. Club mosses (Lycopsids) are primitive, vascular plants that evolved over 375 million years ago. Smaller ones lived during the time of the dinosaurs. These plants live near moisture (in order for their spores to germinate). These fast-growing, resilient plants propagate with rhizomes (underground stems).

Calamites

Calamites (horse-tails) were also found. Horsetail is a primitive, spore-bearing plant. Its side branches are arranged in rings along the hollow stem. Horsetails date from 408-360 million years ago, but are still present today and are an invasive species. Horsetails were an important source of nutrition for plant-eating dinosaurs.