Question

How to differentiate between benthic and planktonic foraminifera?

Answer 1

Generally, Planktonic Foraminifera or Globigerinacea Superfamily can be comprehensibly described by test trochospiral, planospiral or streptospiral; wall macroperforate, with perforations regularly and geometrically arranged; surface may be pitted, with or without spines in adult, but may be smooth in adult excepted for scattered pustules; aperture interiomarginal or areal. As Mr. Afghah nicely mentioned above, keel or carane is the best element to distinguish various genera, so being or not as well as their arrangement can help us to identify the planktonic foraminifera.

According to the attached file, I believe the age of sediments which you are studying on, is so important to identify correctly. Cretaceous or Tertiary? Could you please tell me which one?