Introduction
The coastline of Thailand is about 2,960 km long, of which 750 km is on the west (Andaman Sea) coast, 1,670 km on the Gulf of Thailand, and the remainder (520 km) on over 258 islands, of which the six largest account for 90% (Pitman 1982). Table19.1.1 summarises the distribution of major coastal types. In order to maintain the round-the-world sequence the Andaman Sea coast is presented here, and the Gulf of Thailand coast after Malaysia and Singapore (Gulf of Thailand).
The outline of central and peninsular Thailand is controlled by the effects of an Upper Palaeozoic Hercynian orogeny, modified by a Mesozoic orogeny, which produced fold belts that trend north in the south but northwest toward the head of the Gulf of Thailand. These Cambrian to Triassic sediment were intruded by late Cretaceous to early Tertiary granitic masses, which form four major linear ridges: the first, adjacent to the west coast forms Phuket Island and extends to Ranong and Kanchanaburi; ...