Abstract The Triassic sedimentary rocks of Thailand represent the beginning of a Mesozoic regression which saw widespread marine conditions gradually giving way to continental conditions which spread from the east to the west. The most marine of the Mesozoic systems is therefore the Triassic, which contains in places rich faunas that prove an almost complete succession to be present. This was a period of considerable tectonic and igneous activity and Palaeotethys, which separated the terranes of Sibumasu and Indochina, probably closed at this time. The Triassic granite chains which run the length of the country are described by Cobbing (2011) while the belts of volcanic rocks, many of them Triassic, which run through Northern, NE and SE Thailand, are described by Barr & Charusiri (2011) .

Abstract Northern Thailand is located in a structurally complex area between three major tectonic regimes, a region of extensional tectonics to the south and two major strike-slip zones, the Sagaing fault zone to the west and the Red River fault zone to the northeast. Cenozoic tectonics in northern Thailand resulted from the collision between the Indian plate and Eurasia. The continued indentation of the Indian plate into Eurasia caused polyphase extrusion of Sundaland and the movement of major strike-slip faults. The movement of these faults accompanying the regional east-west extension during Late Oligocene to Early Miocene initiated the formation of the Tertiary basins. Thirty-six major faults and forty-two intra-cratonic depositional basins in northern Thailand have been recognized and delineated using Landsat TM images. More than 70% of these basins are related to strike-slip tectonics. Five basin types have been recognized on the basis of geometric and kinematic considerations. These are fault-tip basins, pull-apart basins, fault-wedge basins, fault zone basins, and extensional basins. The opening and development of these basins was influenced by the movement of NW-trending dextral faults and NE-trending sinistral faults associated with north-south shortening and east-west extension.

Abstract Several of the mineral belts of Southeast Asia pass through Thailand and knowledge of the ore types and metalliferous potential of Thailand may be key to understanding the metallo-genesis of the Southeast Asia region. In 2004, the mining and quarrying sector of Thailand contributed 2.29% to the Gross Domestic Product (GDP) and in 2006 the most valuable minerals produced were coal, gold, gypsum, limestone and zinc ( Wu 2008 ). Minerals and their mineral products have played an important part in the development of the infrastructure and the economy of Thailand in recent years, coming third after agriculture and tourism. The statistics for the mining of metalliferous minerals and the quantities of some derived mineral products in Thailand between 2001 and 2007 are summarized in Table 17.1 . In several instances, rising local demand for a mineral product far exceeds domestic mine output (e.g., the production of steel from iron ore and of antimony) and the shortfall is made up by the import of scrap and mineral ores for processing in the smelter industry. On the other hand, tin mining was for many decades an important activity in Thailand but has declined in recent years in response to reduced international demand. The closure of the majority of the former tin mines has prevented the Thai mining sector benefiting from the recent rise in global metal demand and prices, although the well-established tin smelter industry continues in business and produces tin products for the domestic and overseas markets through the