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Fossil Hunting Information

Fossil Hunting Information

Fossil hunting is a captivating pastime enjoyed by families and people of all ages and levels of experience throughout the year. With just a bit of time spent studying the fundamentals anyone can enjoy the thrill of finding evidence of prehistoric creatures and the environments they lived in. The next web page gives some steering to getting started, including the very best places to look and methods for fossil hunting successfully and safely.

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

Fossils occur commonly all over the world though just a small proportion of former life made it into the fossil report, perhaps less than a billionth. Most living organisms simply decayed with out hint after death. Thus, the abundance of fossils reflects the immense number of organisms that 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, however it wasn’t till approximately 600 million years ago that complicated multicellular life began to enter the fossil report, 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 divided into eras which are additional divided into intervals, of which the most continuously quoted is the Jurassic period (from the Mesozoic period) – well-known 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 circumstances that led to their formation and subsequent exposure. The rocks reveal the conditions current at the time of their formation and the forces that subsequently influenced their character.

There are three main rock types: sedimentary, fashioned from accrued sediment, e.g. sand, silt and skeletal remains; igneous, shaped from molten rock that has cooled and hardened; and metamorphic, sedimentary or Silurian igneous rocks which have been altered significantly by heat and/or pressure.

Fossils are most commonly discovered within sedimentary rocks as a result of favourable situations of burial and restricted alteration through time. Sedimentary rocks form on the Earth’s surface as sediment accumulates in rivers, lakes and on the seafloor in particular. Among the common sedimentary rocks embody: sandstone, composed predominantly of grains of eroded rock; limestone, composed predominantly of shell particles and planktonic skeletons; and shale, fashioned from hardened clay (initially deposited as mud).

Sedimentary rocks might endure considerable change tens of millions of years after deposition leading to 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 kind shale (a sedimentary rock), over time the shale was uncovered to better pressure and heat within the ground, a results of continental movement and/or tectonic activity. Over time the fabric of the shale was altered, changing the unique material and changing it to a metamorphic rock, consequently fossils within the slate are sometimes flattened and distorted.

On very uncommon events fossils may also be discovered within igneous rocks where molten rock escapes to the Earth’s surface and envelops organisms in its path, equivalent to a tree. In this instance if the molten rock cools and hardens in less time than it takes to show the tree to ash, then the hardened rock might form a solid mould around the tree. Over a brief period of time the tree tissues decay leaving an empty chamber inside the rock, some examples even protect the feel of the outer bark on the partitions of the mould.

Having recognised unaltered sedimentary deposits as the primary source for fossils, the following 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 present on the surface; note that the surface rock is usually underlain by older rocks unless significant geological forces have caused buckling/folding of the landscape.