Stratigraphy: Middle Jurrasic sedimentary rocks.

Distribution: Rocks of Tai O Formation crop out in the western part of Lantau Island along its northern coast from Tai O to Sham Wat Wan, and at Chinese University, Sham Chung and Three Fathoms Cove.

Lithology: The Tai O Formation consists of grey to red fine-grained sandstone and siltstone.

Depositional Environment: The Tai O Formation has been interpreted as indicative of deposition on an alluvial plain, crossed by small- to moderately-sized bedload-depositing rivers.

(Fine-grained sandstone, siltstone and sandy siltstone of the Tai O Formation, west of Tai O, Lantau Island)