Northern Thailand and Burma
Much less is known about the Ordovician suc- cession in Thailand north of the peninsula, and the deposits there are generally more tectonised than in the South. However, it is likely that the Lower Ordovician limestones were part of a sin- gle, if now discontinuous sedimentary belt, as shown by, for example, the similarity of the nau- tiloid faunas and lithologies (Kobayashi, 1961; Ingavat et al., 1975; Stait and Burrett, 1984b). It has not been questioned that only one terrane is represented. Northwards into Burma, the Ordo- vician successions are known from the Southern Shan States, which seems to be a northward continuation of the Thai sequence (Garson et al., 1976), including a thick development of ear- ly Ordovician limestones.