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You are currently here: Home > Resources > Fossil collecting - getting started |
In partnership with JuniorGeo |
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Becoming interested in fossils is no surprise, after all who can deny the natural curiosity to explore the origins on modern life? It's this natural desire to explore and question, which makes fossil hunting one of the most rewarding interests.
The following guide introduces the basic concepts necessary for getting started, including background knowledge, where to look and how to maximise the chance of finding good quality specimens.
What do fossil tell us about the prehistoric times?
The shape of the land and sea is constantly changing. Throughout time the movement of continents and varying sea levels result in an ever changing landscape. What is land now, may be sea in the future and likewise what lies beneath the sea today may form the landscape of tomorrow. (Click here to see an animation). Other factors including the accumulation of soils and sediment will also add to the future landscape.
The places we live, including the UK, US, Europe, Asia, Russia and Australia, were all formed over many millions of years. As the rock formed, the creatures which inhabited the land and sea left clues to their existence. These clues are known collectively as fossils.
This understanding was first pioneered by William Smith, who discovered that the history of the rock could be determined by its fossil content. His work led to the creation of geological maps, which use colour to illustrate the age of the rock.
Geological Map (Click here to enlarge)
Geological maps are an essential tool for anyone interested in the study of fossils. The example above shows the basic geology of Europe. The areas shown in pink/yellow indicate rock which was formed in the recent past (Up to 65 million years ago). The earliest fossil bearing rocks are coloured purple (Up to 545 million years ago).
What is a fossil and how to they form?
Fossils are the remains of creatures which existed long ago. Most fossils are the result of 'Permineralization', a process which replaces the original creature or plant with rock-like minerals including Calcite, Iron and Silica).
An ammonite buried beneath layers of sediment
Not all former life was preserved as fossils, in fact the vast majority simply vanished without trace. The most likely materials to survive fossilisation are the hard parts such as shells and objects which in life were constructed from resistant materials, such as Coral. In order for softer materials to survive, the conditions must be extremely favourable.
The most favourable conditions require rapid burial, without the actions of scavengers feeding on the remains.
Fossils come in a variety of sizes, from minute traces to large skeletons. Trace fossils are clues to former life, they result from the activities or presence of creatures and plants. Examples of these traces include footprints, burrows and root tunnels. At the larger end of the scale, fossils also include bones, the largest of which belong to the dinosaurs, which existed between the Triassic and Cretaceous periods.
To learn more about fossil formation click here
Where and when can fossil be found?
Fossils can be found throughout the year all around the UK. The type of fossils depend on the environment and conditions at the time the rock formed. As already discussed, geological maps provide a useful tool to understand these conditions.
The best place to find fossils are areas subject to rapid erosion, as these provide a steady supply of fresh exposures. Among the most rapidly eroded sites are coastlines (Beaches and Cliffs) and inland (Quarries and temporary exposures).
(From Left to Right) Dorset cliffs, Bracklesham Bay clay outcrops and Woodeaton quarry
The erosion of coastal sites can cause the coastline to retreat as much as a metre a year. The rate of erosion depends on the resistance of the rock and the ferocity of the weather. In areas such as Dorset for example, the Jurassic rock is relatively soft and has little resistance against extreme weather.
Throughout the year, the conditions affecting the rate of the erosion differ. During the winter the cliff base is pounded by heavy seas, causing large sections of the cliff face to collapse. Other factors including Wind, Rain and Ice all add to the rate of erosion. During extended periods of sub-zero temperatures, the water logged cliffs freeze, causing the trapped water to turn to ice. As the water freezes, it expands, forcing the rock apart, resulting in the formation of extensive cracks, a process known as frost shattering.
Erosion also occurs during periods of warm, dry weather. At this time of year the sun heats the cliff face, causing it to expand. This expansion/movement can also result in large scale collapse and a steady flurry of smaller pieces.
However some coastal sites are only suitable during the winter, especially sandy beaches. For example, Bracklesham bay in West Sussex is an excellent place to find fossils within the clay. During the winter the stormy conditions shift large volumes of sand along the beach, exposing large sections of clay. However during the summer the sand steadily accumulates, eventually covering all but the tallest outcrops.
Among the other locations to find fossils are quarries. Quarries are manmade excavations into the rock for commercial purposes. Quarry operators extract the rock/minerals for use in a number of ways, depending on the rock/mineral type. The most common quarries excavate rock for use as aggregate for the construction of roads and buildings. Other quarries mine the rock for other purposes, including coal (fossilised wood) - used to fuel power stations and to a lesser extend to heat domestic homes.
Quarries are ideal places to find fossils, especially if the site is working. Before planning a visit, permission must be sought. The reason for acquiring permission is that despite individuals acceptance of their own personal safety, the quarry operator remains liable if an accident was to happen.
What tools do you need to find fossils?
The great thing about fossil hunting is the minimum amount of tools necessary to find, extract and protect your finds. The type of tools and equipment needed vary with the location and rock type. Lu (pictured below) is equipped with most of the tools and clothing necessary for working in quarries and around cliffs.
But beware, new walking boots will soon get muddy! Won't they Lu!...
Tools are not always necessary, especially in more recent sediments formed within the last 65 Million years. Many of these recent fossils are preserved in sand or clay, including those found at Bracklesham Bay in London. In this instance, fossils can be simply picked from the sediment. However, it may be a good idea to bring a digging implement such as a trowel to expose previously unseen sediments.
Clay exposures at Bracklesham Bay
In other areas a most active approach is required to maximise the chance of finding quality specimens. In Dorset the Jurassic clays have had over 150 million years to form. In these areas a hammer and chisel may be necessary to split rocks and extract specimens.
Extracting an Echinoid from foreshore chalk at Eastbourne
Some paleontologists prefer to use a geological hammer, which consists of a chisel like end for splitting rocks. However in our experience a hammer and chisel is usually the better choice, providing a more controlled, precise method for splitting rock.
To learn more about the tools and equipment recommended click here.
What dangers should you be aware of?
Like many activities, fossil hunting can be potentially dangerous. In fact, some areas are so dangerous access is prohibited. When planning a visit, make sure you have as much information about the location as possible. By understanding the dangers will allow the necessary precautions to be taken. Among some on the questions to ask yourself include:
- Is this location a cliff? If so, beware of falling rocks and collapses. Hard hats are highly recommended and is probably best to keep clear of the cliff base (the area directly beneath the cliff face, where rocks are most likely to fall).
- Is this location a quarry? If so, is it working/operational? Working quarries require permission to enter and have a health and safety procedure to follow. Among the dangers to consider include, falling rocks, collapses, deep mud and quarry machinery (especially if working). If in doubt always seek the advice of the quarry owners. It is highly recommended to wear a hard hat, suitable footwear (Walking Boots or Wellies) and high visibility jackets.
- Is this a rocky area? If so, beware of slippery rocks. Walking Boots should be worn to avoid a twisted ankle.
- Is this a coastal location? If so, check the tide times to avoid be isolated by the incoming tide.
- Is the sediment a form of clay? If so, be careful not to become bogged down, it's easy to lose a pair of boots this way!
Buying and selling fossils - a view
For many people the opportunity to visit certain areas of the world is restricted by both time and money. In this case a good way of extending your collection is by trading your finds with other collectors. However before deciding, it's worth noting a few key points.
- Always check the fossil includes information about it's source, geology and species. Many fossils are simply traded for their aesthetic appearance, without accurate information, which diminishes their monetary and scientific value. If you're trading your own finds make sure you provide this information to the recipient.
DON'T trade fossils without their location/source information
- Make sure the fossil is adequately protected during transit, especially if dealing internationally.
- Beware of fakes. Many fossils are replicas of actual fossils, especially where complete skeletons are concerned. Although there's no single piece of information to protect you from these traders, a little common sense is usually enough.
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