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Where can I find Fossils?
Fossil formation occurs when some trace of organic life (whether it be a footprint or an actual foot) is preserved beyond the original organism's decomposition. Examples include fossilized tissue, excrement, egg shells, trackways, burrows, and nests. The process of fossil formation varies depending upon the initial remains and the conditions under which they are preserved.
In some cases, organic tissues such as bones, skin and feathers, etc. are replaced by minerals from the ground through leaching. The result is a sort of statue of the original organic material. In other instances, the sediments surrounding the organic remains harden into rock, creating a mold of the original and thereby preserving its external form.
In the case of fossilized footprints, the
sediments in which the print was formed can harden
into rock casting a partial mold of the foot which
left the print. Fossil formation can also occur when
an organism becomes immersed and preserved in a
resinous substance like tree sap. This sort of
fossil was popularized by the blockbuster hit movie
Jurassic Park. The fossilized mosquito from which
the cloning scientists extract dinosaur DNA was
preserved in amber.
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TYPES OF Fossils & evidence of ancient life: |
PLANT REMAINS
Hard seeds and woody structures are more commonly found than
flowers and leaves. The flowers and leaves themselves are not preserved,
but the carbon impression of them can leave most of the detail showing
their delicate structure.
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ANIMAL REMAINS
Teeth, bones and shells are much more commonly
found than the rarer skin, flesh, fur, and hair and feather
parts. Usually only 1 or 2 bones and or teeth are found at a
time and you can count yourself extremely lucky if you come
across or unearth a whole skeleton.
There has been the odd rare occasion when an entire mammoth has been discovered in places such as Alaska or Siberia, frozen solid for millions of years. These ‘frozen fossils’ have preserved not only the bones and teeth but the entire animal.
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MOLLUSKSJust like today when you can pick up sea shells along the
sea shore, during prehistoric times the shells of sea
animals also collected along the banks plains and coastline,
when the sea retreated the shells became covered in mud,
silt and sands and can be found today throughout many
geological periods. |
 AMBER(Fossil Tree Resin) - Amber is fossil tree resin (tree sap),
sometimes fossil insects can be found trapped in the amber.
Amber is highly sought after and is usually made into
jewelry.
There are a number of locations along the UK
coast where amber is found, Southwold is one of the most
popular locations in East Anglia.Amber is comes in
several colors, such as orange, yellow,
green or red. |
COAL, GAS, OILMore commonly known as 'Fossil Fuels'. The burning of fossil
fuel is said to be speeding up climate change by increasing
levels of Carbon Dioxide (Co2) in the atmosphere causing
heat to become trapped causing 'The Greenhouse effect'.
Coal is actually dead fossil plants and animals
carbonized and compressed over time which is why it is so
highly flammable. Oil is also the remains of animals and
plants but was formed during marine environments. Natural Gas
was formed from rotting vegetation. |
 MOULDS AND CASTS(trace fossils) - Often fossils found are not the original
plant or animal material, but the mould or cast of it.
During fossilization the original material sometimes
dissolves away leaving a cavity, which, over time fills in
with other dissolved substances. This type of fossil is
known as a mould. Casts are another type of fossil found.
Casts are hollowed impressions of the original fossil or
mould. Types of casts that can be found are the foot prints
and animal trails. |
 RIPPLE MARKS AND MUD CRACKSOccasionally, rocks that were formed in shallow seas, lakes
or rivers have been left with ancient ripple marks on them
caused when the soft mud dried. Mud cracks were formed in a
similar way, when the soft wet mud dried out quickly.Ripple marks and mud – cracks can tell us much about the
climate and environment when they were formed. For instance,
we know there must have been water, sun and warm
temperatures at the time they were made. |
 COPROLITES
The fossilized excrement of animals. The discovery of the true
nature of this material was made by the English geologist William
Buckland, who observed that certain convoluted bodies occurring
in the Lias (rock strata of Early Jurassic age, 187 to 208 million
years old) of Gloucestershire had a form that would have been
produced by their passage in thesoft state through the intestines
of reptiles or fishes. These bodies had long been known as fossil
fir cones and bezoar stones. Buckland's conjecture that they were
of fecal origin and similar to the excrement of hyenas was
confirmed on analysis; they were found to consist essentially of
calcium phosphate and carbonate and not infrequently contained
fragments of unaltered bone. The name coprolites (from Greek
kopros, “dung”; and lithos, “stone”) was accordingly given them
by Buckland. |
 FOOTPRINTS (trace fossils)Fossilized footprints of dinosaurs and mammals can be found.
The photo shows a dinosaur footprint at Hastings, UK. These
are formed in certain conditions such as mud when the
dinosaur walked over muddy land, over time sediments laid on
top and the footprints can be found today. |
 BORINGS (trace fossils)Borings are small channels
and tunnels made by worms and mollusks that lived millions
of years ago. Such fossils are common.
Sometimes petrified mood shows borings also. |

GASTROLITHSGastroliths are smooth, rounded pebbles
found in rib cages of dinosaurs. These stones probably aided the
dinosaurs’ digestion just as gravel in their gizzards helps chickens
crush grain. Polished gastroliths are found only in “dinosaur country.” |

ARTIFACTSArtifacts are objects such as stone tools
or weapons made by ancient man. Found in many parts of the world, the
oldest have been found with bones of animals now extinct. The first
stone artifacts were crude and difficult to recognize. More recent ones
were chipped and polished to make beautiful implements. |

SEDIMENTARY ROCKSSedimentary rocks are formed from pre-existing rocks or pieces of once-living organisms.
They form from deposits that accumulate on the Earth's surface. Sedimentary rocks often have distinctive layering or bedding. Many of the picturesque views of the desert southwest show mesas and arches made of layered sedimentary rock. |

STRATAIn geology and related fields, a stratum
(plural: strata) is a layer of rock or soil with internally consistent
characteristics that distinguishes it from contiguous layers. Each layer
is generally one of a number of parallel layers that lie one upon
another, laid down by natural forces. They may extend over hundreds of
thousands of square kilometers of the Earth's surface.
Strata are typically seen as bands of different colored or
differently structured material exposed in cliffs, road cuts, quarries,
and river banks. Individual bands may vary in thickness from a few
millimeters to a kilometer or more. Each band represents a specific mode
of deposition: River silt, beach sand, coal swamp, sand dune, lava bed,
etc. |

LIMESTONELimestone is a sedimentary rock composed of the mineral calcite (calcium carbonate). The primary source of this calcite is usually marine organisms. These organisms secrete shells that settle out of the water column and are deposited on ocean floors as pelagic ooze (see lysocline for information on calcite dissolution). Secondary calcite may also be deposited by supersaturated meteoric waters (groundwater that precipitates the material in caves).
This produces speleothems such as stalagmites and stalactites. Limestone makes up approximately 10 percent of the total volume of all sedimentary rocks.
Pure limestones are white or almost white. Because of impurities, such as clay, sand, organic remains, iron oxide and other materials, many limestones exhibit different colors, especially on weathered surfaces. Limestone may be crystalline, clastic, granular, or dense, depending on the method of formation. Crystals of calcite, quartz, dolomite or barite may line small cavities in the rock. Chert or Flint nodules are common in limestone layers. Bands of limestone emerge from the Earth's surface in often spectacular rocky outcrops and islands.
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SHALEShale is a fine-grained sedimentary rock that is formed by the compression of muds. This type of rock is composed primarily of quartz and minerals that are found in clay.
Shales can be broken easily into thin, parallel layers. Shale is ground up for use in making bricks and cement. |

SANDSTONESandstone is an arenaceous sedimentary rock composed mainly of feldspar and quartz and varies in
color (in a similar way to sand), through grey, yellow, red, and white. Since sandstones often form highly visible cliffs and other rock formations, certain colors of sandstone may be strongly identified with certain regions. For instance, much of the American West is well-known for its red sandstones.
Rock formations that are primarily sandstone usually allow percolation of water, and are porous enough to store large quantities, making them valuable aquifers. Fine grained aquifers, such as sandstones, are more apt to filter out pollutants from the surface than are rocks with cracks and crevices such as
limestone or other rocks fractured from seismic activity. |

RIPPLE MARKS AND MUD CRACKSRipple marks and mud
cracks characterize many sedimentary rocks formed in shallow waters. For
example, ripple marks are common In shale.
Mud cracks may form as mud and clays dry. These imply the presence
of sunlight, water and moderate temperatures - conditions related to the
possibilities of life.
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PSEUDOFOSSILSPseudofossils are rock structures that resemble fossils. They may have any shape and
often look like parts or plants or animals. A geologist will usually recognize a pseudofossil at once, but an amateur may be misled. Pseudofossils resemble fossils only in
external form. They never have the detailed structure of true fossils. They way occur in improbable situations, as tor instance a footprint” in rock formed long before any creatures walked on land.
Pseudofossils are formed in many ways. Some are water-worn fragments of rock. Concretions which form in sedimentary rock way contain a fossil, though most do not.
Concretions, harder than the rock in which they occur, are often found on
the surface. Some minerals form dendrites or fanlike deposits on or in rocks. Moss agates
are dendrites, not fossil moss.Other examples of common
pseudofossils include:
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Concretions
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Cone in Cone structures
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dolomite "pseudo-coral"
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pyrolusite dendrites on dolomite
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polished moss agate
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