Resumen de Microfacies and environmental significance of hypercalcified demosponges of the Upper Jurassic Esfandiar platform (Shotori Mountains, Tabas Block, east-central Iran)
During the Middle Oxfordian to Lower Kimmeridgian, Esfandiar platform flourished under arid climatic conditions. Seven distinct microfacies are recognized in the Esfandiar Limestone Formation in the Dehuk area, south of the Shotori Mountains, east-central Iran. These microfacies are characteristic of a sheltered inner platform in a eutrophic environment. This was supported by the morphology of hypercalcified demosponges with a chaetetid skeleton. The low-energy environment of the platform interior was episodically subjected to storms as is evidenced by chaotic and poorly bioconglomeratic layers indicating in situ reworking of the platform sediments. At the high-energy platform margin, ooid shoals protected the platform interior from the open sea.
