Radiolarian chert is a sedimentary rock composed predominantly of silica, formed from the accumulation of radiolarian skeletons. These rocks are significant in paleontology and stratigraphy for understanding deep-sea environments, the global carbon cycle, and the age dating of oceanic crust.
Source Moore, T. C. (1973). “Radiolarian Stratigraphy and the Cenozoic History of the Equatorial Pacific.” Geological Society of America Bulletin, 84(5), 1803-1828.