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Micropaleontology
Majed Turkistani
Outline
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Definition.
Why microfossils.
Microfossil classification based on Wall-type.
Siliceous walled-microfossil.
Phosphoric walled-microfossil.
Organic walled-microfossil.
Calcareous walled-microfossil.
Definition
• Micropaleontology
is
a
branch
of palaeontology that studies microfossils, or
fossils that require the use of a microscope to
see the organism, its morphology and its
characteristics details.
• Not larger than four millimeters,
commonly smaller than one millimeter
and
Diatoms
Foraminifera
Why?
• They are important in biostratigrephical
studies because:
– They are abundant.
– They are geographically widespread.
– They have short time in geological time.
– The nature of their habits: Planktonic, Nectonic
and benthic.
Why?
• Microfossils of the deep-sea provide good global
environmental and ecological changes during the
past geological time. This can be done by
studying changes in assemblages of microfossils
and of changes in their shell chemistry.
• They are excellent tool for sedimentary
rock dating and for paleoenvironmental
reconstruction.
• They are tool of Geoarchaeology used in
archaeological
reconstruction
of
human
habitation sites and environments.
Wall type
Calcareous
Siliceous
Phosphatic
Organic
Siliceous
• Their shell wall is mad of
silicates.
• They can be found in the
deep sea since their shells
are resistant to dissolved.
• Under the microscope
they are transparent.
• Two
microfossil
assemblages under this
categories:
Radiolarian
and Diatoms.
Phosphatic
• Their shells are mad
of phosphate.
• The most common
microfossils under
this
categories:
Shark tooth.
Organic
• Their shell wall is
mad of organic
matter.
• Their shells are not
resistant
and
quickly dissolve.
• Most
common
groups:
Pollen,
Spores
and
Achritachs.
Calcareous
• Their shell wall is mad
of calcium carbonate.
• They widely distribute
from coast to deepsea.
• The most common
groups: Foraminifera
and Coccolithophores.