Difference between revisions of "AY Honors/Fossils/Answer Key"

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{{honor_header|2|1944|Nature|General Conference}}
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[[Image:Sharksteeth-castlehain.jpg|thumb|right|300px|Collecting fossilized shark's teeth is an easy way to begin collecting fossils. They are often found in abundance on public beaches. The teeth shown here were collected in Castle Hain, [[North Carolina]], and are from the [[Eocene]] and [[Cretaceous]] divisions.]]
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{{AY Master|Conservation}}
 
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==1. Make a collection of at least ten different kinds of fossils and label each with its name and geographic location. ==
 
−
==2. Have a brief definition of each of the following in your notebook: ==
 
−
;a. Geology: Geology is the science and study of the solid matter that constitutes the Earth.
 
  
−
;b. Fossils: Fossils are the mineralized or otherwise preserved remains or traces (such as footprints) of animals, plants, and other organisms.
+
'''Fossil collecting''' describes the extraction of fossilised material for profit, pleasure, or scientific study. [[Fossil]]s - the preserved remains of long-dead organisms - are found in many places where [[sedimentary rock]]s, such as [[clay]]stones, [[shale]]s, [[limestone]]s, and [[sandstone]]s, are exposed. Only certain sedimentary [[Rock (geology)|rock]]s harboured the appropriate environmental conditions to preserve and yield fossils, which are often concentrated along particular bedding planes within the rocks.<ref>{{cite web
−
;c. Catastrophism: Catastrophism is the idea that Earth has been affected by sudden, short-lived, violent events that were sometimes worldwide in scope.
+
|url=http://www.rasny.org/fossil/NYstrat.htm
−
;d. Paleontology:  Paleontology is the study of prehistoric life forms on Earth through the examination of plant and animal fossils.
+
|title=STRATIGRAPHY Fossil-Bearing Rocks
−
;e. Graptolite: A Graptolite is a fossil colonial animal known chiefly from the Upper Cambrian through the Lower Carboniferous (Mississippian) periods.
+
|publisher=The Rochester Academy of Science
−
;f. Trilobite: Trilobites are extinct arthropods that form the class Trilobita. They appeared in the 2nd Epoch (Series 2) of the Cambrian period and flourished throughout the lower Paleozoic era before beginning a drawn-out decline to extinction when, during the Late Devonian extinction, all trilobite orders, with the sole exception of Proetida, died out.
+
|accessdate=2007-09-11
−
;g. Dinosaur: A dinosaur is any of various extinct reptiles.
+
}}</ref>
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;h. Mammoth: A mammoth is any species of an extinct genus of proboscidean (elephants and their extinct relatives), often with long curved tusks and, in northern species, a covering of long hair.
 
−
;i. Mastodon: Mastodons are members of the extinct genus Mammut of the order Proboscidea and form the family Mammutidae; they resembled, but were distinct from, the woolly mammoth which belongs to the family Elephantidae. Mastodons were browsers and mammoths were grazers.
 
−
;j. Crinoid: Crinoids, also known as "sea lilies" or "feather-stars", are marine animals that make up the class Crinoidea of the echinoderms (phylum Echinodermata).  There are only a few hundred known modern forms, but crinoids were much more numerous both in species and numbers in the past. Some thick limestone beds dating to the mid- to late-Paleozoic are entirely made up of disarticulated crinoid fragments.
 
−
;k. Lingula: Lingula is a genus of brachiopods.
 
−
;l. Calamite: A fossil made when sediment filled the hollow stem of a plant.
 
−
;m. Foraminifera:  The Foraminifera are a large group of unicellular organisms with reticulating pseudopods, fine strands of cytoplasm that branch and merge to form a dynamic net. They typically produce a test, or shell, which can have either one or multiple chambers, some becoming quite elaborate in structure. About 275,000 species are recognized, both living and fossil.
 
−
;n. Radiolaria: Radiolaria are amoeboid protozoa that produce intricate mineral skeletons, typically with a central capsule dividing the cell into inner and outer portions, called endoplasm and ectoplasm. They are found as zooplankton throughout the ocean, and because of their rapid turn-over of species, their tests are important diagnostic fossils found from the Cambrian onwards.
 
−
;o. Paleozoic: The Paleozoic Era is the earliest of three geologic eras of the Phanerozoic eon. The Paleozoic era is defined by geologists as spanning from roughly 542 million years ago to roughly 251 million years ago.
 
  
−
{| class="toccolours" style="margin-left:auto; margin-right:auto;"
+
== Finding fossils ==
−
|-
+
Fossils are generally found in sedimentary rock with differentiated strata<!--strata is plural of stratum--> representing a succession of  deposited material.<ref>{{cite web
−
! style="background:rgb(154,217,229);" colspan="3" | Phanerozoic eon
+
|url=http://www.sdnhm.org/kids/fossils/ffwhere.html
−
|-
+
|title=Where to look forfossils
−
! style="background:rgb(153,192,141);" | Paleozoic era
+
|publisher=San Diego National History Museum
−
! style="background:rgb(103,197,202);" | Mesozoic era
+
|accessdate=2007-09-06
−
! style="background:rgb(250,253,1);" | Cenozoic era
+
}}</ref>
−
|}
+
 
−
;p. Mesozoic: Lying between the Paleozoic and the Cenozoic, Mesozoic means 'middle animals'. It is often called the 'Age of the Dinosaurs'.
+
The occurrence of fossil bearing material depends on environmental factors before and after the time of preservation. After death, the first preserving factor is a rapid burial in water bodies or [[terrestrial]] sediment which would help in preserving the specimen. These rocks types are usually termed [[clastic rock]], and are further subdivided into fine, medium and coarse grained material. While fossil's can be found in all grain typed, more detailed specimens are found in the fine grained material <ref name=potts2003/>.  A second type of burial is the [[non-clastic rock]], form where the rock is made up of the precipitation of compacted fossil material, types of rock include [[limestone]] and [[coal]]. The third fossil bearing material is the [[evaporates]], which precipitate out of concentrated dissolved salts to form [[Nodule (geology)|nodular deposit]]s, examples include [[rock salt]] and [[phosphate]] concentrations. The evaporates are usually associated with [[gastropod]], [[algae]], [[vertebrate]], and [[trace fossil]]s.
−
;q. Cenozoic: The Cenozoic Era is the latest of three geologic eras of the Phanerozoic eon. Geologists define this era as having started about 65 million years ago, when the age of the dinosaurs ended.
+
[[Image:07PaleoFTb11.JPG|thumb|right|300px|[[College of Wooster]] students collecting fossils as part of their invertebrate [[paleontology]] course. This is a roadside outcrop of [[Ordovician]] [[limestone]]s and [[shale]]s in southeastern [[Indiana]].]]
−
;r. Pleistocene: The Pleistocene epoch on the geologic timescale is the period from 1,808,000 to 11,550 years before present. The Pleistocene epoch had been intended to cover the world's recent period of repeated glaciations, or the Ice Age.
+
After burial various factors are at work to endanger the current fossil's preserved state. Chemical alteration  would change the mineral composition of the fossil, but generally not its appearance, [[lithification]] would distort its appearance, the fossil itself may be fully or partially dissolved leaving only a fossil mold.<ref>
−
;s. Paleobotany: Paleobotany is the branch of paleontology or paleobiology dealing with the recovery and identification of plant remains from geological contexts, and their use for the biological reconstruction of past environments. Paleobotany includes the study of terrestrial plant fossils, as well as the study of prehistoric marine photoautotrophs, such as photosynthetic algae, seaweeds or kelp.
+
{{cite web
−
;t. Pelecypod: Pelecypod are molluscs belonging to the class Bivalvia. They typically have two-part shells, with both valves being symmetrical along the hinge line. The class has 30,000 species, including scallops, clams, oysters and mussels.
+
|url=http://www.sdnhm.org/kids/fossils/ffmore.html
−
;u. Brachiopod: Brachiopods are two-shelled marine animals with an external morphology superficially resembling pelecypods (for instance, clams) of phylum Mollusca to which they are not closely related. It is estimated by paleobiologists that 99 percent of all documented lamp-shell species are both fossils and extinct.
+
|title=How to look for fossils
 +
|publisher=San Diego National History Museum
 +
|accessdate=2007-09-06
 +
}}</ref><ref name=potts2003>{{cite_book |last=Potts |first=Joanna |editorlink=Joanna Potts|year=2003 |title=Guide to Fossils |location=London |publisher=Phillips|pages=31-34pp |isbn=0-540-08374-7}}</ref>
 +
 
 +
Areas where sedimentary rocks are being eroded include exposed [[Mountain]]ous areas, [[river bank]]s and [[river bed|beds]] and engineering features like [[quarries]] and [[road cuts]]. Generally in appearance, a fossil will be either a different colour to the surrounding rock, because of the different mineral content, will have a defining shape and texture or a combination of both.<ref>
 +
{{cite web
 +
|url=http://www.sdnhm.org/kids/fossils/ffmore.html
 +
|title=How to look for fossils
 +
|publisher=San Diego National History Museum
 +
|accessdate=2007-09-06
 +
}}</ref> Dried up natural lake beads <ref>{{cite web 
 +
|url=http://acl.arts.usyd.edu.au/research/cuddie/cuddie.html 
 +
|title=Dinnertime at Cuddie Springs: hunting and butchering megafauna? 
 +
|publisher=Judith Furby, School of Archaeology, The University of Sydney, NSW 2006   
 +
|accessdate=2007-09-11  |accessdate=2007-09-11
 +
}}</ref> and caves in the form of [[pitfall trap]]s <ref>{{cite web |url=http://www.parks.sa.gov.au/naracoorte/caves/index.htm 
 +
|title=Development of the Naracoorte Caves 
 +
|publisher=South Australian Parks Web 
 +
|accessdate=2007-09-11 
 +
}}</ref> also has an occurrence of a recent fossil fauna for the locality as is the case with [[Cuddie Springs]] and [[Naracoorte Caves]] in Australia.
 +
 
 +
Fossils are not to be found in areas of [[igneous rock]] (except in some beds between lava flows). In rocks which have undergone [[metamorphism]], they are usually so distorted that they are difficult to recognize or have been destroyed completely.
 +
 
 +
Artificial exposures, such as road cuttings or quarries, can often be good collecting spots, along with continually eroding river or coastal exposures. [[Coal mining]] operations often yield excellent fossil [[plant]]s, but the best ones are to be found not in the [[coal]] itself but in the associated sedimentary rock deposits called [[coal measures]].
 +
 
 +
In hilly regions the best sections are often those exposed at the sides of streams that have cut into the [[bedrock]].
 +
 
 +
Wave washed sea cliffs and foreshore exposures are often good places to search for fossils, but always be aware of the state of the [[tide]]s in the area. Never take chances by climbing high cliffs of crumbling rock or clay (many have died attempting it).
 +
 
 +
Exposures of softer rocks, such as clays and [[sand]]s, can be good collecting spots. However inland sections tend to degrade rapidly, becoming overgrown, and are lost forever.
 +
 
 +
== Collecting ethics ==
 +
To collect fossils, there are various legal realities that must be observed. Permission should be sought before collection begins on private land.<ref>{{cite web
 +
|url=http://ology.amnh.org/paleontology/stuff/findfossils_2.html
 +
|title=Do's and don'ts for fossil hunters
 +
|publisher=American Museum of National History
 +
|accessdate=2007-09-06
 +
}}</ref>
 +
 
 +
Hammering the rocks in [[national parks]] and other areas of natural beauty is often discouraged and in most cases is illegal.
 +
 
 +
== Equipment ==
 +
It is important to have the right kind of field equipment when looking for fossils, and safety should always be an important concern.
 +
 
 +
A [[hard hat]] is essential protection from loose stones that may be dislodged from cliffs above, but will not protect the wearer from larger falling rocks. Hard hats are normally a requirement in operational quarries.
 +
 
 +
Safety goggles and protective gloves are also essential, as rocks can be sharp and dangerous; safety goggles will protect eyes from chips produced while hammering, and gloves protect the hands.
 +
 
 +
A collector need dress appropriately for collecting trips, taking into account the climate and terrain of the area. Sturdy footwear, such as walking or hiking boots with steel toes, are recommended. A hammer, chisel and wrapping materials are the basic equipment required for fossil collecting, along with a stout rucksack or canvas bag for carrying equipment and fossil finds. The [[steel]] of many ordinary hammers is too soft for use on most type of rock. The steel may splinter, and the flying fragments cause injury to the person using the hammer, or others in the vicinity.  The hammer should always strike away from the body.
 +
The head of a [[geological hammer]] or rock pick is made from specially hardened steel designed for use on rocks. The head is either firmly attached to a wooden shaft, or the hammer have the head and the shaft formed from one piece of steel. The head may have any combination of a square face, a tapered point, or a straight chisel edge. The point of such picks are not meant for striking rock directly, but for tapping rock (such as shale) open along planes and for prying: the hammer end is used for striking.
 +
 
 +
A convenient weight for a general purpose [[geological hammer]] or rock pick is around 1 kg (2 to 3 pounds). For breaking very hard rocks one may need a hammer of between 3 and 6.5 kg (7 and 14 pounds) in weight, with a correspondingly longer and thicker shaft. A hammer that is too heavy is tiring to use and results in unsafe work.
 +
 
 +
For extracting fossils from harder rocks, a sturdy [[mallet]] and cold steel chisels may also be  required. Usually one needs a range of chisels in size from small ones with a sharp edge of about 1 cm (quarter of an inch), to much larger and heavier chisels. A broad-bladed chisel is often very useful for splitting rocks along their bedding plane.
 +
 
 +
Different types of rocks will break differently and a beginner should put in a little practice, getting the feel for a particular type of rock before he or she starts hammering out fossils. It is all too easy to ruin a specimen with one ill-placed blow of a hammer.
 +
 
 +
Extracting a specimen that is embedded in solid rock may prove to be a long and difficult process. Before attempting to extract a specimen, the collector should make sure that it is feasible to remove it without destroying or damaging it. Leaving sufficient rock beneath the specimen to protect it from fracturing; excess matrix can be trimmed at a later time.
 +
 
 +
For soft [[sediment]]s and unconsolidated deposits, such as sands, [[silt]]s and clays, a spade and a flat-bladed [[trowel]] or stout bladed [[knife]] may be the most useful tools for clearing the area around a fossil. [[Brush]]es are also useful for removing loose sediment from around fossils.  
 +
 
 +
A sieve is used to separate fossils from sands and [[gravel]]s. A smaller mesh is required in order to avoid losing small fossils. One practical difficulty with using sieves in the field is that they easily become clogged, especially when the material sieved has a high moisture content. However, under dry weather conditions the more durable fossils, such as teeth and bones, can be quickly and easily sieved out of loose sands. Shaking the sieve is always liable to damage or destroy fragile fossils.
 +
 
 +
If there is water available, such as on a beach or next to a stream, the material containing the fossils can be sieved wet and the matrix gradually washed away. Wet sieving is a technique that is frequently used for the collection of small [[mammal]]ian fossils, and by using this technique even the smallest specimens may be recovered.
 +
 
 +
== Preservation and documentation ==
 +
A knowledge of the precise location a fossil was found greatly increases its scientific value. Details of the parent rock strata, the location of the find, and other fossil material associated with the find help scientists to place the fossil in context, in terms of the time, location and situation in which the organism lived.<ref>{{cite web
 +
|url=http://www.sdnhm.org/kids/fossils/ffwhat.html
 +
|title=Discover what you have
 +
|publisher=San Diego National History Museum
 +
|accessdate=2007-09-06
 +
}}</ref>
 +
 
 +
[[Data logging|Logging]], photographing, and sketching may accompany detailed field notes to assist in the locating of a fossiliferous outcrop; individual fossils are ideally labeled with a locality number alongside their specimen number for later identification.
 +
 
 +
To avoid damage to fossils, collectors store them in a breathable bag, ideally made from a breathable fabric such as [[Tyvek]], to avoid the growth of mold; suitable padding is also applied.
 +
 
 +
Occasionally, large fragile specimens may need to be surrounded and supported using a jacket of [[plaster]] before their removal from the rock: This protects the fossil, protecting it from shattering. If a fossil is to be left in situ, a cast may be produced, using [[plaster of paris]] or [[latex]] - whilst not preserving every detail, such a cast is inexpensive, easier to transport, causes less damage to the environment, and leaves the fossil in place for others to enjoy.  Subtle fossils which are preserved solely as impressions in sandy layers, such as the [[Ediacaran biota|Ediacaran fossils]], are usually sampled by means of a cast, which shows up detail more clearly than the rock itself.
  
−
==3. Visit a museum where fossils are on display and make a written or oral report of your trip. ==
 
−
==4. Describe the process of the proper removal of delicate specimens. Tell how a skeleton of a dinosaur or other gigantic fossil would be removed. Why should beginners not remove such specimens? What should be done by the beginner when he finds what is obviously a valuable fossil? ==
 
−
==5. Explain the difference in the account scientists give for the presence of fossils as related by evolutionists and creationists. ==
 
−
==6. From the Bible and writings of Ellen G. White cite statements to explain the origin of the following: ==
 
−
===a. Coal===
 
−
===b. Petroleum===
 
−
===c. Fossils===
 
−
===d. Limestone===
 
 
==References==
 
==References==
−
[[Category:Adventist Youth Honors Answer Book|{{SUBPAGENAME}}]]
+
<references/>
 +
==External links==
 +
* http://www.english.fossiel.net/ - Fossil collecting locations in Europe and the rest of the World
 +
 
 +
==See also==
 +
 
 +
* [[Mary Anning]] -- an early fossil hunter
 +
* [[Fossil fuel]]s
 +
* [[Fossil park]] -- a protected fossiliferous area
 +
* [[Geologic time scale]]
 +
* [[History of geology]]
 +
* [[History of paleontology]]
 +
* [[Index fossil]]s
 +
* [[Invertebrate paleontology]]
 +
* [[List of transitional fossils]]
 +
* [[List of notable fossils]]
 +
* [[List of fossil sites]] ''(with link directory)''
 +
* [[Macrofossil]]s -- covers easily-visible fossils
 +
* [[Microfossil]]s -- covers microscopic life
 +
* [[Paleobiology]] -- fossils and biology
 +
* [[Paleobotany]] -- the study of ancient plants
 +
* [[Paleontologist]]s
 +
* [[Paleozoology]] -- animal history
 +
* [[Prehistoric life]]
 +
* [[Pseudofossil]]s -- false fossil-like rock
 +
* [[Rockhounding]]
 +
* [[Sedimentary rock]]
 +
* [[Trace fossil]]s -- indirect evidence of life
 +
* [[Treatise on Invertebrate Paleontology]] (1953 to 2006) -- a 50-volume reference
 +
* [[Vertebrate paleontology]]
 +
 
 +
[[Category: Collecting]]
 +
[[Category: Fossils]]
 +
[[Category: Geology]]
 +
[[Category: Paleontology]]

Revision as of 22:53, 7 February 2008

Collecting fossilized shark's teeth is an easy way to begin collecting fossils. They are often found in abundance on public beaches. The teeth shown here were collected in Castle Hain, North Carolina, and are from the Eocene and Cretaceous divisions.

Fossil collecting describes the extraction of fossilised material for profit, pleasure, or scientific study. Fossils - the preserved remains of long-dead organisms - are found in many places where sedimentary rocks, such as claystones, shales, limestones, and sandstones, are exposed. Only certain sedimentary rocks harboured the appropriate environmental conditions to preserve and yield fossils, which are often concentrated along particular bedding planes within the rocks.&

Finding fossils

Fossils are generally found in sedimentary rock with differentiated strata representing a succession of deposited material.&

The occurrence of fossil bearing material depends on environmental factors before and after the time of preservation. After death, the first preserving factor is a rapid burial in water bodies or terrestrial sediment which would help in preserving the specimen. These rocks types are usually termed clastic rock, and are further subdivided into fine, medium and coarse grained material. While fossil's can be found in all grain typed, more detailed specimens are found in the fine grained material &. A second type of burial is the non-clastic rock, form where the rock is made up of the precipitation of compacted fossil material, types of rock include limestone and coal. The third fossil bearing material is the evaporates, which precipitate out of concentrated dissolved salts to form nodular deposits, examples include rock salt and phosphate concentrations. The evaporates are usually associated with gastropod, algae, vertebrate, and trace fossils.

College of Wooster students collecting fossils as part of their invertebrate paleontology course. This is a roadside outcrop of Ordovician limestones and shales in southeastern Indiana.

After burial various factors are at work to endanger the current fossil's preserved state. Chemical alteration would change the mineral composition of the fossil, but generally not its appearance, lithification would distort its appearance, the fossil itself may be fully or partially dissolved leaving only a fossil mold.&&

Areas where sedimentary rocks are being eroded include exposed Mountainous areas, river banks and beds and engineering features like quarries and road cuts. Generally in appearance, a fossil will be either a different colour to the surrounding rock, because of the different mineral content, will have a defining shape and texture or a combination of both.& Dried up natural lake beads & and caves in the form of pitfall traps & also has an occurrence of a recent fossil fauna for the locality as is the case with Cuddie Springs and Naracoorte Caves in Australia.

Fossils are not to be found in areas of igneous rock (except in some beds between lava flows). In rocks which have undergone metamorphism, they are usually so distorted that they are difficult to recognize or have been destroyed completely.

Artificial exposures, such as road cuttings or quarries, can often be good collecting spots, along with continually eroding river or coastal exposures. Coal mining operations often yield excellent fossil plants, but the best ones are to be found not in the coal itself but in the associated sedimentary rock deposits called coal measures.

In hilly regions the best sections are often those exposed at the sides of streams that have cut into the bedrock.

Wave washed sea cliffs and foreshore exposures are often good places to search for fossils, but always be aware of the state of the tides in the area. Never take chances by climbing high cliffs of crumbling rock or clay (many have died attempting it).

Exposures of softer rocks, such as clays and sands, can be good collecting spots. However inland sections tend to degrade rapidly, becoming overgrown, and are lost forever.

Collecting ethics

To collect fossils, there are various legal realities that must be observed. Permission should be sought before collection begins on private land.&

Hammering the rocks in national parks and other areas of natural beauty is often discouraged and in most cases is illegal.

Equipment

It is important to have the right kind of field equipment when looking for fossils, and safety should always be an important concern.

A hard hat is essential protection from loose stones that may be dislodged from cliffs above, but will not protect the wearer from larger falling rocks. Hard hats are normally a requirement in operational quarries.

Safety goggles and protective gloves are also essential, as rocks can be sharp and dangerous; safety goggles will protect eyes from chips produced while hammering, and gloves protect the hands.

A collector need dress appropriately for collecting trips, taking into account the climate and terrain of the area. Sturdy footwear, such as walking or hiking boots with steel toes, are recommended. A hammer, chisel and wrapping materials are the basic equipment required for fossil collecting, along with a stout rucksack or canvas bag for carrying equipment and fossil finds. The steel of many ordinary hammers is too soft for use on most type of rock. The steel may splinter, and the flying fragments cause injury to the person using the hammer, or others in the vicinity. The hammer should always strike away from the body. The head of a geological hammer or rock pick is made from specially hardened steel designed for use on rocks. The head is either firmly attached to a wooden shaft, or the hammer have the head and the shaft formed from one piece of steel. The head may have any combination of a square face, a tapered point, or a straight chisel edge. The point of such picks are not meant for striking rock directly, but for tapping rock (such as shale) open along planes and for prying: the hammer end is used for striking.

A convenient weight for a general purpose geological hammer or rock pick is around 1 kg (2 to 3 pounds). For breaking very hard rocks one may need a hammer of between 3 and 6.5 kg (7 and 14 pounds) in weight, with a correspondingly longer and thicker shaft. A hammer that is too heavy is tiring to use and results in unsafe work.

For extracting fossils from harder rocks, a sturdy mallet and cold steel chisels may also be required. Usually one needs a range of chisels in size from small ones with a sharp edge of about 1 cm (quarter of an inch), to much larger and heavier chisels. A broad-bladed chisel is often very useful for splitting rocks along their bedding plane.

Different types of rocks will break differently and a beginner should put in a little practice, getting the feel for a particular type of rock before he or she starts hammering out fossils. It is all too easy to ruin a specimen with one ill-placed blow of a hammer.

Extracting a specimen that is embedded in solid rock may prove to be a long and difficult process. Before attempting to extract a specimen, the collector should make sure that it is feasible to remove it without destroying or damaging it. Leaving sufficient rock beneath the specimen to protect it from fracturing; excess matrix can be trimmed at a later time.

For soft sediments and unconsolidated deposits, such as sands, silts and clays, a spade and a flat-bladed trowel or stout bladed knife may be the most useful tools for clearing the area around a fossil. Brushes are also useful for removing loose sediment from around fossils.

A sieve is used to separate fossils from sands and gravels. A smaller mesh is required in order to avoid losing small fossils. One practical difficulty with using sieves in the field is that they easily become clogged, especially when the material sieved has a high moisture content. However, under dry weather conditions the more durable fossils, such as teeth and bones, can be quickly and easily sieved out of loose sands. Shaking the sieve is always liable to damage or destroy fragile fossils.

If there is water available, such as on a beach or next to a stream, the material containing the fossils can be sieved wet and the matrix gradually washed away. Wet sieving is a technique that is frequently used for the collection of small mammalian fossils, and by using this technique even the smallest specimens may be recovered.

Preservation and documentation

A knowledge of the precise location a fossil was found greatly increases its scientific value. Details of the parent rock strata, the location of the find, and other fossil material associated with the find help scientists to place the fossil in context, in terms of the time, location and situation in which the organism lived.&

Logging, photographing, and sketching may accompany detailed field notes to assist in the locating of a fossiliferous outcrop; individual fossils are ideally labeled with a locality number alongside their specimen number for later identification.

To avoid damage to fossils, collectors store them in a breathable bag, ideally made from a breathable fabric such as Tyvek, to avoid the growth of mold; suitable padding is also applied.

Occasionally, large fragile specimens may need to be surrounded and supported using a jacket of plaster before their removal from the rock: This protects the fossil, protecting it from shattering. If a fossil is to be left in situ, a cast may be produced, using plaster of paris or latex - whilst not preserving every detail, such a cast is inexpensive, easier to transport, causes less damage to the environment, and leaves the fossil in place for others to enjoy. Subtle fossils which are preserved solely as impressions in sandy layers, such as the Ediacaran fossils, are usually sampled by means of a cast, which shows up detail more clearly than the rock itself.

References

  1. ↑ "STRATIGRAPHY Fossil-Bearing Rocks". The Rochester Academy of Science. http://www.rasny.org/fossil/NYstrat.htm. Retrieved 2007-09-11.
  2. ↑ "Where to look forfossils". San Diego National History Museum. http://www.sdnhm.org/kids/fossils/ffwhere.html. Retrieved 2007-09-06.
  3. ↑ 3.0 3.1 Potts, Joanna (2003). Guide to Fossils. London: Phillips. pp. 31-34pp. Template:Hide in printTemplate:Only in print.
  4. ↑ "How to look for fossils". San Diego National History Museum. http://www.sdnhm.org/kids/fossils/ffmore.html. Retrieved 2007-09-06.
  5. ↑ "How to look for fossils". San Diego National History Museum. http://www.sdnhm.org/kids/fossils/ffmore.html. Retrieved 2007-09-06.
  6. ↑ "Dinnertime at Cuddie Springs: hunting and butchering megafauna?". Judith Furby, School of Archaeology, The University of Sydney, NSW 2006. http://acl.arts.usyd.edu.au/research/cuddie/cuddie.html. Retrieved 2007-09-11.
  7. ↑ "Development of the Naracoorte Caves". South Australian Parks Web. http://www.parks.sa.gov.au/naracoorte/caves/index.htm. Retrieved 2007-09-11.
  8. ↑ "Do's and don'ts for fossil hunters". American Museum of National History. http://ology.amnh.org/paleontology/stuff/findfossils_2.html. Retrieved 2007-09-06.
  9. ↑ "Discover what you have". San Diego National History Museum. http://www.sdnhm.org/kids/fossils/ffwhat.html. Retrieved 2007-09-06.

External links

See also

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