Cretaceous. The Septarian Nodules were formed during the Cretaceous Period. Periodic volcanic eruptions killed the smaller sea life which sank to the sea bed and started decomposing. The minerals in the shells and carcasses attracted sea floor sediments which accumulated around the carcasses and formed nodules or mud balls. When the ocean eventually receded, the mud balls dried out and began to shrink and crack into the beautiful patterns that you see inside.
Ruth Jacobs Collection
The University of Toledo
Digital Initiatives, University of Toledo Libraries
environmental sciences; virtual exhibitions
"Septarian Nodule" (2017). Rock and Mineral Exhibit. 110.