Miocene sea-floor subsidence and later subaerial solution subsidence structures in the Maltese Islands

Abstract

Roof collapse within extensive cavern systems is argued to be responsible for the formation of solution subsidence structures throughout the Maltese Islands. Many of these subsidences are post-Miocene in age but the present study reveals the existence often larger structures, produced by subsidence under submarine conditions during three discrete episodes associated with normal Miocene carbonate deposition. A Lower Tertiary episode of emergence and cavern formation is inferred to account for the development of these latter structures. It is considered that a further episode of solution within pre-Miocene cavern levels, during later Tertiary times, is responsible for subsequent formation of new structures and further movement within existing ones, especially in western Gozo.