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Fossil hunting is an interesting pastime enjoyed by households and individuals of all ages and levels of experience throughout the year. With just somewhat time spent studying the fundamentals anybody can enjoy the thrill of discovering proof of prehistoric creatures and the environments they lived in. The following page gives some steering to getting started, together with the perfect places to look and techniques for fossil hunting effectively and safely.

The fashionable use of the word ‘fossil’ refers to the physical proof of prehistoric life that's preserved from a time period prior to recorded human history. There is no universally agreed age at which the evidence can be termed fossilised, however it’s broadly understood to encompass anything more than a few thousand years. Such a definition includes our prehistoric human ancestry and the ice age fauna as well as more ancient fossil groups such as the dinosaurs, ammonites and trilobites.

Fossils occur commonly world wide though just a small proportion of former life made it into the fossil file, perhaps less than a billionth. Most residing organisms merely decayed with out trace after death. Thus, the abundance of fossils reflects the immense number of organisms which have lived and the vast length of time over which the rocks have accumulated.

The earliest fossils discovered date from 3.5 billion years ago, nevertheless it wasn’t until approximately 600 million years ago that complex multicellular life began to enter the fossil file, and for the needs of fossil hunting nearly all of effort is directed towards fossils of this age and more recent.

The geologic timescale is split into eras which are further divided into durations, of which essentially the most incessantly quoted is the Jurassic interval (from the Mesozoic period) – famous for the abundance of dinosaurs at this time. To view the geologic timescale

The first step towards understanding the place to look for fossils is to appreciate the distribution of fossil bearing rocks and the conditions that led to their formation and subsequent exposure. The rocks reveal the circumstances present on the time of their formation and the forces that subsequently influenced their character.

There are three primary rock types: sedimentary, formed from accumulated sediment, e.g. sand, silt and skeletal stays; igneous, formed from molten rock that has cooled and hardened; and metamorphic, sedimentary or igneous rocks which were altered significantly by heat and/or pressure.

Fossils are most commonly found within sedimentary rocks due to the favourable circumstances of burial and limited alteration by way of time. Sedimentary rocks type on the Earth’s surface as sediment accumulates in rivers, lakes and on the seafloor in particular. Among the many common sedimentary rocks embrace: sandstone, composed predominantly of grains of eroded rock; limestone, composed predominantly of shell particles and planktonic skeletons; and shale, fashioned from hardened clay (originally deposited as mud).

Sedimentary rocks could endure considerable change millions of years after deposition resulting in a new rock type, e.g. slate. These ‘altered’ rocks are collectively generally known as metamorphic. Slate was initially laid down as a muddy sediment which was then compacted and hardened to kind shale (a sedimentary rock), over time the shale was uncovered to higher pressure and heat within the ground, a result of continental movement and/or tectonic activity. Over time the fabric of the shale was altered, changing the unique cloth and changing it to a metamorphic rock, consequently fossils within the slate are sometimes flattened and distorted.

On very uncommon occasions fossils may also be found within igneous rocks the place molten rock escapes to the Earth’s surface and envelops organisms in its path, akin to a tree. In this instance if the molten rock cools and hardens in less time than it takes to turn the tree to ash, then the hardened rock could type a stable mould across the tree. Over a brief time frame the tree tissues decay leaving an empty chamber inside the rock, some examples even protect the texture of the outer bark on the walls of the mould.

Having recognised unaltered sedimentary deposits as the principle source for fossils, the subsequent step is to grasp the place such rocks are located. Geology maps are a helpful place to begin as they reveal the age and type of rocks present at the surface; note that the surface rock is mostly underlain by older rocks unless significant geological forces have caused buckling/folding of the landscape.
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