Stratigraphy: Jurassic dyke swarm with an age of approximately 146.5 ± 0.2 million years before present.

Distribution: Dykes of the East Lantau Rhyodacite are concentrated mainly in northern and eastern Lantau Island, with minor distribution in central Lantau Island and on Ma Wan, the Soko Islands.

Lithology: Feldsparphyric rhyodacite to porphyritic granite dykes.