Spores and pollen are part of the reproductive processes of flowering and non-flowering plants, algae and fungi.

Assorted spores and pollen.

Spores

• the reproductive process of (mainly) algae and fungi – terrestrial and fresh-water origins but very susceptible to offshore transport by river and wind
• geologic range: Precambrian – Recent (fungal spores), Silurian – Recent (plant spores)
• used in thermal maturation studies (spore colour index)

Pollen

• reproductive process of flowering or non-flowering plants – terrestrial and fresh-water origins but very susceptible to offshore transport by river and wind
• geologic range: Late Devonian – Recent (for Gymnosperm pollen); Cretaceous – Recent (for Angiosperm pollen)

Spores and pollen grains, because of their extremely small size and weight, have the potential to be transported by wind and water over very large distances (as intended!). It is not uncommon to find terrestrial pollen grains in samples from deep-water, offshore sediments. Whilst clearly not originally from that environment, their presence can still aid in age-determination and also in paleoclimate and environmental evaluations as they can indicate conditions in the hinterland at the time of deposition.