El Cámbrico inferior del Cerro del Hierro (Sevilla). Propuesta de itinerario paleontológico

Abstract

Geological characteristic of the karstic landscape of Cerro del Hierro is showed with special emphasis in the stratigraphy and paleontology of the materials. These ones belong to the Lower Cambrian, corresponding the oldest to an Ovetian stage age (- 530 m.a), that contain a rich fauna of archaeocyatha represented by Nochoroicyathus? sp., Erismacoscinus sp., Alconeracyathus andalusicus (Simon, 1939) and Protopharetra? sp., as well as laminar constructions of algae and stromatolites Overlying, lower Marianian layers occur with a rich fauna of trilobites of high biostratigraphic interest. These ones are represented by Strenuella sp. A, Delgadella souzai (Delgado, 1904), Micmacca? sp., Eops sp. and Saukianda andalusiae. Fossil hyoliths, inarticulated brachiopods, sponges and numerous trace fossils (Sericichnus, Planolites) produced by soft bodies are present too. All these characteristics point out the Cerro del Hierro as a place of great interest to know one of the first evidences of the oldest life in the past and being able to reconstruct the paleoenvironmental conditions of this primitive marine ecosystem. These circumstances, together with the landscaping value and the mining history of the site, convert this enclave is one of the points of greater geologic interest within the Sierra Norte of Seville Natural Park. Consequently, an itinerary that allows to recognize and to value this geologic history is proposed.