Laboratories and preparation techniques

Preparation of samples in a paleontological laboratory Source: BGR

Microfossils are small fossil remnants that belong to various groups of animals and plants that mainly lived in the ocean, but also in fresh water or on land. After they died, they were deposited on the sea floor or the floors of rivers, lakes or moors, together with sediment particles. Thus, before microfossils can be analysed, they need to be separated from the sediment.

Depending on the the shell or skeleton of the organisms, microfossils consist of various substances such as calcium carbonate, silica, calcium phosphate or organic materials. Therefore different laboratories and techniques are required for specific preparation steps:

• Calcareous microfossils like foraminifers or ostracods as well as mesofauna are usually processed in the microfossil laboratory by wet sieving with water, hydrogen peroxide or otherchemicals. The remains may also contain organic remnants, e.g., megaspores, seeds or wood.
  
  
• There are many organic-walled microfossils such as dinocysts, pollen and spores, known as palynomorphs. These fossils are extracted in the palynological laboratory, predominantly by using hydrochloric and hydrofluoric acid.
  
  
• Coccolithophores and remains of very tiny organisms with calcareous skeletons are also named calcareous nannofossils. They are processed in the nannofossil laboratory using an alkaline solution made of ammonia and calcium carbonate saturated, deionised water.