Spores and pollen

Question 1

What are spores and pollen made of?

Answer 1

• organic walled microfossils or palynomorphs
• Sporopollenin is a very resistant organic compound
• 30 microns to a few hundred microns in diameter

Question 2

Name the land plant families that produce spores:

Answer 2

Seedless plants

• Bryophytes
• Lycophytes
• Pteridophytes (Ferns)

Question 3

Whats the difference between bryopytes and pteridophytes?

Answer 3

• Bryophyte spores are a single size

- Pteridophyte spores can be homosporous or heterosporous with larger female spores

Question 4

What is the geological range of spores and pollen?

Answer 4

Spores: Ordovician to recent (earliest crytospores)
Pollen: L. Devonian to recent

Question 5

Where does a spore germinate through?

Answer 5

Their laesura

Question 6

Describe spore morphologies:

Answer 6

• Monolete spores have a single laesura, tetragonal tetrad

- Trilete spores have a Y-shaped mark, tetrahedral tetrad

Question 7

What did mid Silurian plants lack?

Answer 7

425Ma Trachaeophytes had no roots

Question 8

Describe spore wall structure:

Answer 8

External surfaces may be smooth or sculptured with either positive (protrusive) or negavtive (indenting) elements

Question 9

What microfauna do mid devonian spores also look like?

Answer 9

Acritarchs

Question 10

Name the pollen producing plant familys

Answer 10

seed plants

• gymnosperms (non- flowering)
• angiosperms (flowering)

Question 11

Describe pollen evolution:

Answer 11

Devonian: earliest pollen
Carboniferous: Large increase in diversity creating forests and gymnosperm pollen developed
Lower Cretaceous (or Upper Jurassic): Angiosperms developed

Question 12

What are the types of gymnosperm pollen sacs?

Answer 12

They are air sacs from the expansion of the pollen wall

• Monosaccate
• Bisaccate
• Trisaccate?

Question 13

What are the types of angiosperm pollen grains?

Answer 13

• Monads (single grains)
• Dyads (pairs)
• Tetrads (fours)
• Polyads (groups of fours)

Question 14

Spore and pollen uses:

Answer 14

• Biostratigraphy of marine + non-marine strata (terrestrial)
• Palaeoenvironmental analysis
• Palaeogeography
• Primary record for Plant taxonomy and evolution
• Palaeoclimate reconstruction

Question 15

What are the 3 key applications for organic walled microfossils?

Answer 15

• In forensic application (terrestrial palynology used to place criminals at the scene)
• Palaeoclimate/palaeoenvironmental analysis (e.g. evolution of rivers)
• Search for hydrocarbons, where spores, pollen, dinoflagellates and acritarchs all play a huge role

Question 16

How do plants have an environmental impact on river systems:

Answer 16

Plants bind sediment together and possible cause meandering before that most rivers were braided

• increased meandering
• increased mudrock proportion
• increased sandstone maturity
• increased bioturbated fine sediments and lateral accretion surfaces (Davies and Gibling 2012)

Question 17

Describe how you use organic microfossils to find oil:

Answer 17

Look at Arabian peninsula - Palaeozoic succession

• Acritarch diversity reflects palaeodepth (Ordovician in China)
• Find max flooding surface from max carbon sequitation
• Find biostratigraphy and environment against chronostratigraphic record
• Acritarchs = marine phytoplankton and tell us the max diversity/abundance on the palaeo open marine/ shelf environments
• In L.Silurian finding acritarchs and chitinozoans suggest another max flooding surface and therefore oil!