East Kirkton Quarry

East Kirkton Quarry, or simply East Kirkton, is a former limestone quarry in West Lothian, Scotland. Today, it is famous for its many fossils. The most famous layer of rock there is from about 341 million years ago, during a time called the Viséan stage of the early Carboniferous Period. The quarry is a big hole about 200 meters long located in the town of Bathgate.

The rocks at East Kirkton are made mostly of volcanic tuff, limestone, and silica. These rocks came from large freshwater lakes that were near hot springs and volcanism. Three main layers of rock can be seen there: the East Kirkton Limestone, the Little Cliff Shale, and the Geikie Tuff.

Many important fossils have been found at East Kirkton, including early four-limbed animals and small creatures with many legs, like millipedes and arachnids. The site was forgotten by scientists for many years until a fossil collector named Stan Wood bought the land in 1985. Since then, many new species have been discovered there, and most of them are found only at East Kirkton. These include Westlothiana (an early reptile-like animal), Balanerpeton (an early type of amphibians), and Pulmonoscorpius (a very large scorpion). The area around East Kirkton was dry woodland with mineral-rich lakes, different from the swampy forests where many other fossils from the same time are found.

History

Early history (1825–1983)

East Kirkton has been an interesting place for scientists since the 1820s. Back then, scientists were trying to understand how rocks formed. Some thought rocks came from water, while others believed they came from hot, melted rock deep inside the Earth. East Kirkton had both kinds of rocks close together, which made scientists curious.

The first scientist to study East Kirkton was John Fleming in 1825. He thought the rocks came from hot groundwater. Later, Samuel Hibbert studied the site and agreed, noting that the rocks looked like they formed in freshwater. After the quarry stopped being used in 1844, it was mostly forgotten. In 1861, Archibald Geikie realized that the limestone came from two different places. For many years, East Kirkton didn’t get much attention.

Stan Wood's fossil discoveries (1984 – present)

In 1984, a fossil collector named Stan Wood found an ancient animal skull piece in the old quarry waste. This discovery brought new interest to the site. Wood bought the quarry and began searching for more fossils with scientists from the University of Cambridge. They found many important fossils, including early amphibians and other animals.

One of the most famous finds was a small animal called Westlothiana, first thought to be one of the oldest reptiles but later understood to be an amphibian closely related to reptiles. These discoveries helped scientists learn more about life from long ago. East Kirkton is now protected as an important scientific site.

Geology

The East Kirkton Quarry has layers of rock up to 19 meters thick from the Bathgate Hills Volcanic Formation. These rocks are similar to those found north of Linlithgow and are part of the larger Strathclyde Group in Scotland’s Midland Valley.

Scientists used special dating methods and found the quarry’s rocks are about 341 million years old, placing them in the early part of the Carboniferous Period. The quarry has three main rock layers: the Geikie Tuff, Little Cliff Shale, and East Kirkton Limestone.

The Geikie Tuff is mostly made of volcanic ash and contains fish scales, plant bits, and tiny shells. The Little Cliff Shale is thinner and has more fossils, including scorpions and more plants and fish. The East Kirkton Limestone is the thickest and richest in fossils, with many land animals, insects, and plants, but few fish. This layer shows signs of an ancient lake environment.

Palaeoenvironment

During a time called the Dinantian, the area where East Kirkton is now would have been a warm, lowland area with faults and cooled lava flows shaping the land. These features would have changed the paths of rivers and created lakes, some of which may have formed in old volcanic craters. There were many small volcanoes in the area, and they often erupted in ways that created hot springs.

To the north and east of East Kirkton was a large lake or waterway system called Lake Cadell. This lake helped form the layers of rock and soil in the West Lothian Oil-Shale Formation. West of East Kirkton were dry, volcanic highlands called the Clyde Plateau. The East Kirkton Limestone formed where these two different landscapes met, allowing a rich plant and animal community to develop in the Bathgate area.

East Kirkton was close to the equator during its time, with a warm climate that slowly became wetter. There was enough rain to support forests and lakes, but not so much that large coal forests formed. Some layers of rock suggest that hot springs were common when the East Kirkton Limestone was being created.

Paleobiota and paleoecology

East Kirkton Quarry in Scotland is famous for its old fossils from around 341 million years ago. Most of the fossils come from layers of limestone, especially from a thin black shale layer. These fossils show animals that lived in or near shallow water, unlike some fish that needed deeper water.

The fossils include many special types of animals that are only found in this area, though some groups appear in other places from the same time. Some fully water-living animals are missing, which might be because they hadn’t evolved yet or lived in different places. The site has more land animals compared to other fossil sites in Scotland, but a few could live in water or move between land and water.

The area also had many different kinds of fish, though not all have been studied enough. Some fish were shaped like tuna and were general hunters, while others had flat, deep bodies. Fossils of waste material, called coprolites, have been found too. These might have come from fish, some sharks, or even the land animals.

Besides fish and land animals, the site had many small creatures like tiny shellfish that likely were important food for others. There were also plants, mostly pieces of wood and leaves, showing the area had forests or open woodlands that sometimes caught fire.

Plants were preserved in different ways, either by being replaced with minerals or squished into thin films. Common plant fossils include wood from gymnosperms and leaves from ferns.

Tetrapods of East Kirkton
Genus / Taxon	Species	Strata	Material	Images
Balanerpeton	B. woodi	East Kirkton Limestone (Units 52-86)	Over 30 specimens, including skulls and nearly complete skeletons
Eldeceeon	E. rolfei	East Kirkton Limestone (Unit 76)	Four partial skeletons, two of which are nearly complete
Embolomeri	Indeterminate	East Kirkton Limestone (Unit 82)	Skull fragments (pterygoid, quadratojugal, lower jaw)
Eucritta	E. melanolimnetes	East Kirkton Limestone (Unit 82)	Four partial skeletons and an isolated skull roof
Kirktonecta	K. milnerae	East Kirkton Limestone (Unit 82)	Single nearly complete skeleton
Ophiderpeton	O. kirktonense	East Kirkton Limestone (Unit 82)	Five partial skeletons, including skull material
Silvanerpeton	S. miripedes	East Kirkton Limestone (Unit 82)	Nine partial skeletons, including skull material
Westlothiana	W. lizziae	East Kirkton Limestone (Unit 82)	Two nearly complete skeletons
Temnospondyli	Indeterminate	East Kirkton Limestone	Isolated ribs
Termonerpeton	T. makrydactylus	East Kirkton Limestone (Unit 82)	Single partially articulated posterior torso

Cartilaginous fish (Chondrichthyes and Acanthodii) of East Kirkton
Genus / Taxon	Species	Strata	Material	Images
Acanthodidae?	Indeterminate	Little Cliff Shale (Unit 36) Geikie Tuff (Units 26-29)	Three specimens: a disarticulated skeleton and fragments of a fin spine and pectoral girdle
Climatiidae?	Indeterminate	Geikie Tuff (Unit 31)	Single bony plate
Diplodoselache	D. woodi?	East Kirkton Limestone (Unit 37) Little Cliff Shale (Units 35-36)	Three teeth
Tristychius	T. arcuatus?	East Kirkton Limestone (Unit 37) Little Cliff Shale (Units 32-36)	Fin spines (two complete and six fragmentary) up to 4 cm (1.6 inches) in length

Arthropods of East Kirkton
Genus / Taxon	Species	Strata	Material	Images
Brigantibunum	B. listoni	East Kirkton Limestone (Unit 82)	Single compressed partial specimen
Cyrtoctenus	C. sp.	East Kirkton Limestone	Two isolated combs
cf. Dunsopterus	cf. D. sp.	East Kirkton Limestone	Isolated femur
Hibbertopterus	H. scouleri	East Kirkton Limestone	Partially articulated specimens and isolated fragments
Myriapoda	Unnamed	East Kirkton Limestone (Units 47-82)	Multiple specimens, six of which are complete enough to describe
Pulmonoscorpius	P. kirktonensis	East Kirkton Limestone (holotype from unit 47 and other referred specimens from various units) Little Cliff Shale (Unit 34.4)	16 complete specimens and hundreds of cuticle fragments
Scorpionida	Indeterminate	East Kirkton Limestone, Little Cliff Shale	Cuticle fragments