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Fossil hunting is a fascinating pastime loved by families and people of all ages and levels of experience all through the year. With just a little time spent learning the basics anyone can benefit from the thrill of finding proof of prehistoric creatures and the environments they lived in. The next page offers some steering to getting began, including the most effective places to look and methods for Cambrian fossil hunting effectively and safely.

The trendy use of the word ‘fossil’ refers to the physical evidence of prehistoric life that's preserved from a time period previous to recorded human history. There is no such thing as a universally agreed age at which the proof may be termed fossilised, nevertheless 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 historic fossil teams such because the dinosaurs, ammonites and trilobites.

Fossils occur commonly all over the world although just a small proportion of former life made it into the fossil report, maybe less than a billionth. Most dwelling organisms merely decayed without trace after death. Thus, the abundance of fossils displays the immense number of organisms which have lived and the huge 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 roughly 600 million years ago that complicated multicellular life started to enter the fossil report, and for the purposes of fossil hunting the vast majority of effort is directed towards fossils of this age and more recent.

The geologic timescale is split into eras which are further divided into periods, of which essentially the most frequently quoted is the Jurassic period (from the Mesozoic period) – well-known for the abundance of dinosaurs at this time. To view the geologic timescale

Step one towards understanding the place to search for fossils is to appreciate the distribution of fossil bearing rocks and the situations that led to their formation and subsequent exposure. The rocks reveal the circumstances current at the time of their formation and the forces that subsequently influenced their character.

There are three main rock types: sedimentary, formed from collected sediment, e.g. sand, silt and skeletal stays; igneous, fashioned 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 discovered within sedimentary rocks because of the favourable circumstances of burial and restricted alteration by time. Sedimentary rocks type on the Earth’s surface as sediment accumulates in rivers, lakes and on the seafloor in particular. Among the widespread sedimentary rocks include: sandstone, composed predominantly of grains of eroded rock; limestone, composed predominantly of shell debris and planktonic skeletons; and shale, fashioned from hardened clay (initially deposited as mud).

Sedimentary rocks might endure considerable change thousands and thousands of years after deposition resulting in a new rock type, e.g. slate. These ‘altered’ rocks are collectively often called metamorphic. Slate was originally laid down as a muddy sediment which was then compacted and hardened to form shale (a sedimentary rock), over time the shale was uncovered to better 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 original cloth and converting it to a metamorphic rock, consequently fossils within the slate are sometimes flattened and distorted.

On very uncommon events fossils can also be found within igneous rocks the place molten rock escapes to the Earth’s surface and envelops organisms in its path, comparable 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 may type a solid mould across the tree. Over a short time frame the tree tissues decay leaving an empty chamber inside the rock, some examples even preserve the feel of the outer bark on the walls of the mould.

Having recognised unaltered sedimentary deposits as the principle supply for fossils, the subsequent step is to understand where such rocks are located. Geology maps are a useful place to begin as they reveal the age and type of rocks current on 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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