Deep Time, from before the time of Aslan

 

 

The trace plant leaf or stem found in the broken coal 
(central brown rectangle).

Whilst undertaking a partial water change of his tropical fish aquarium, Syd Carp dropped a piece of coal onto the floor. The lump of coal split to reveal a partial trace plant fossil.  Syd showed this remnant of Carboniferous life to his Australian friend  Barry 'Digger' Stone who was much intrigued down under.  

The Carboniferous Period in the United Kingdom

The Carboniferous Period, spanning approximately 359 to 299 million years ago, was a time of profound geological and biological development, particularly well represented in the United Kingdom's fossil record. Named for the vast coal-bearing strata it left behind, the period is divided into two epochs: the Mississippian (early Carboniferous) and the Pennsylvanian (late Carboniferous), though in the UK it is traditionally divided into the Dinantian and Silesian.

Geology and Environment

During the early Carboniferous, much of the British Isles lay near the equator and was submerged beneath warm, shallow tropical seas. This setting fostered the development of extensive limestone formations, such as those found in the Peak District, Mendip Hills, and South Wales, forming ideal conditions for the fossilization of marine life. Over time, as the period progressed, these seas gave way to extensive coastal swamps, delta plains, and flooded forests, particularly in areas like Yorkshire, Scotland, and the Forest of Dean.

The later Carboniferous saw the formation of immense peat-forming forests, composed of towering lycopsids, calamites (giant horsetails), and ferns, which eventually formed the coal seams of Northern England, South Wales, and Central Scotland. The repeated flooding and burial of these forests created the alternating layers of coal and shale characteristic of this period.

Fossils of the Carboniferous in the UK

The fossil record from this time is among the richest in the British Isles. Notable finds include:

Marine Invertebrates: Early Carboniferous limestones preserve an abundance of marine fossils, including crinoids (sea lilies), brachiopods, corals, and gastropods.

Marine invertebrate.
 - collected by Anita and George Roberts from the foreshore,
Howick Bay, Northumberland

Coral
- collected by Anita and George Roberts from the foreshore,
Holy Island, Northumberland

Plant Fossils: Late Carboniferous coal measures are famous for fossilized lepidodendrons (scale trees), sigillaria, and sphenopterids. Impressions of their leaves and bark are commonly found in coal shales.

Lepidodendron leaf
- collected by Anita and George Roberts
from near Bolsover, Chesterfield, Derbyshire

Terrestrial Arthropods: Giant millipedes like Arthropleura and large dragonfly-like insects such as Meganeura (with wingspans up to 70 cm) have been discovered in Carboniferous deposits.

Wing of a Carboniferous insect
found in shale at Radstock Colliery tip by George and Alice Roberts(now Boon)
(fossil now sadly lost)

Early Tetrapods: The UK also holds significant fossils of early land vertebrates, including primitive amphibians and reptile-like tetrapods, especially from sites like East Kirkton Quarry in Scotland.

These fossils provide a critical window into the transition from marine to terrestrial life and the rise of complex forest ecosystems that altered the planet's atmosphere by sequestering vast amounts of carbon dioxide.

Chart: Geological Time Scale – Position of the Carboniferous Period

Eon                 Era                 Period          Approx. Start (MYA) Approx. End (MYA)

Phanerozoic Paleozoic Cambrian          541                           485

                                                Ordovician        485                           444

                                                Silurian           444                           419

                                                Devonian          419                           359

                                                Carboniferous  359                                  299

                                                Permian         299                                  252

Mesozoic                                Triassic         252                                  201

                                                Jurassic          201                                 145

                                                Cretaceous  145                                 66

Cenozoic                                 Paleogene  66                                 23

                                                Neogene          23                                 2.6

                                                Quaternary  2.6                                 Present

Note: In the UK, the Carboniferous is further subdivided into:

Dinantian (Lower Carboniferous)

Silesian (Upper Carboniferous), which includes:

Namurian

Westphalian

Stephanian (less developed in the UK)

"Although there is some debate between Mr Tumnus and two beavers, the time before Aslan is thought to predate the Cambrian Period" - C.S. Lewis