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Science on board - News from Core 24R: we passed from middle to early Miocene!
Submitted by Alessia Cicconi on Wed, 03/01/2017 - 08:53
We are still heading to our basement target (hard magmatic rocks) but passing through the sediments that are becoming older and older.
In core 24R our paleontologists found some species that allowed them to say "we are coring sediments from early Miocene." It means the boundary between middle and early Miocene that is 15.97 Ma (Million years ago)
In core 23 the nannofossil specialists found a typical association with Discoaster deflandrei (those are the "big stars" in the teaser image, that disappeared, as species, at 15.80 Ma) followed in core 24 by an association with a lot of Sphenolithus heteromorphus (that appeared, as species, at 17 .71 Ma) and Sphenolithus belemnos (that disappeared, as species, 17.95 Ma).
The occurrence of these species permits to assign an age to the cores.
So, the core 23R is older than 15.80 Ma (Millions of years ago) and core 24R is older than 17.7 Ma
Discoaster deflandrei. (Credits: Claudia Lupi & IODPSO)
Sphenolithus heteromorphus.(Credit: Claudia Lupi & IODPSO)
Sphenolithus belemnos. (Credit: Claudia Lupi & IODPSO)