Mixon Limestone Pebble – Microfossils

Foraminifera in Alveolina Limestone from the Hampshire Basin, England. Probably Bartonian.

Foraminifera in Alveolina Limestone from the Hampshire Basin, England. Probably Bartonian.

An unidentified foram with alveolina in Mixon Limestone

An unidentified foram with Alveolina in Mixon Limestone

This page is about an examination of a foramaniferal rich Mixon (Alveolina) Limestone pebble originally dredged from the English Channel about 7 miles off the the West Sussex coast.

Mixon Limestone is thought to date to the Eocene, Bartonian stage, and to relate to a Tethys Sea shallow benthic zone (SBZ 17) at its far western edge in the Hampshire Basin of England.

The examination is done with a USB micropscope offering magnifications of X20 and X400 under reflected light.

Grinding and polishing is done with diamond sharpening stones of grit sizes 200, 300, 400, 600.  Further polishing is sometimes done using up to 2400 grit emery paper.

Some digital enhancement is sometimes done in Photoshop, usually restricted to cropping and adjusting brightness/contrast with the “Levels” tool.

Also, sometimes a stitching programme is used to combine multiple photos together.

Foraminiferal rich limestone pebble.
Foram rich limestone pebble.
More on the forams in this pebble are to be found by clicking on the relevant link in the page list at the right hand side of the screen. 
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