- Deep drilling in the southern Tyrrhenian Sea floor revealed a continental and oceanic substratum covered by upper Miocene and younger sedimentary successions.
- The acoustic facies of its substratum has neither the characteristics of the continental crust nor those of the oceanic crust.
- Paleocene fossil outcrops abound in the glauconite rich gray clay substrata of the creek banks exposed beneath the deep rich surface soils.
- For example, barnacles maintain a relatively large proportion of their total surface area in contact with the underlying substratum, and display body temperatures that are tightly coupled with ground temperature.
- In recent habitats, Lyreidus does not inhabit shallow, inshore environments but, instead, is found in outer shelf and slope environments, generally on soft substrata.