Abstract Due to the economic importance of its hydrocarbon and coal resources, more is known of the Tertiary than of any other part of the stratigraphic succession in Thailand. Tertiary sedimentary rocks occur both on- and offshore and they are generally associated with rift basins formed in extensional, transtensional or strike –slip settings (Fig. 10.1 ). In the Gulf of Thailand and Central Thailand the rift basins have been covered by extensive post-rift sag basins, while the Mergui Basin is in a post-rift passive margin setting. Thermal subsidence has yet to cover the rift basins of Northern Thailand. The basins trend north-south through the centre of the country onshore, and underlie much of the Gulf of Thailand and Andaman Sea. The Tertiary was a period of considerable tectonic activity and hence the timing of a basin’s subsidence, its location and the nature of its basin-fill and lateral facies variations are all tied to its structural development. The Tertiary structure is discussed by Morley et al. (2011) and further data on the Tertiary stratigraphy and structure are to be found in Ratanasthien (2011) and Racey (2011) ; the wider plate-tectonic context of the Tertiary structure is discussed by Searle & Morley (2011) . Information on the offshore Tertiary basins has been obtained entirely through hydrocarbon exploration and production activities since the late 1960s, and comprises seismic (both 2D and 3D) and borehole data. A number of the onshore basins in Northern and Central Thailand have

Abstract The production of dimension stones is well established in Thailand and the country has considerable processing capacities in the region, second only to China. The geological background of Thailand provides a huge potential of dimension stones, including magmatic, metamorphic and sedimentary rocks. The NE part of the country is made up by the Khorat Plateau with the main sandstone resources at its western margin. Metamorphic carbonate rocks are predominantly distributed along the border of a basin area in central Thailand. The western part of the country is characterized by magmatic belts that comprise the resources of igneous rocks. Large quantities of the dimension stone potential were used in the first part of the 1990s, when the domestic economy underwent a considerable upturn. The most important region for the production of granitoid rocks is the Tak batholith in northern Thailand. Therefore, the Tak granitoids are discussed as a case study with respect to petrophysical and depositional characteristics.