Latest Permian radiolarian fauna from Klaeng, eastern Thailand

The role of strike-slip faults in the displacement of the Palaeotethys suture zone in Southeast Thailand

“…And yet no rocks laid down in that ocean have yet been found: the Inthanon Zone has not been recognized in Southeast Thailand. The rocks cropping out in Belt II, described earlier, might have been thought of as representing the missing Inthanon Zone, but the latest Permian radiolarian-bearing chert which Sashida et al (2000b) considered to be pelagic has been re-interpreted as hemipelagic by Yoshihito Kamata (pers. comm.…”

“…She does state that a Permian age for her Yaang Formation cannot be ruled out, and this writer takes the view that the Khao Wang Chik sections of both authors are of latest Permian age. Sashida et al (2000b) interpreted the facies of their Sections I and II as deep-marine, pelagic, and this interpretation was accepted by Kamata et al (2009) who, however, had not examined the rocks in the field. On examining the rocks at outcrop Kamata later noted the terrigenous clastic intercalations in the chert successions, which caused him to modify his earlier interpretation to hemipelagic (Y.…”

“…Two c. 20 m sections, about 150-200 m apart, were sampled and described by Sashida et al (2000b) at Khao Wang Chik, about 7 km NNW of Klaeng town. They described the rocks as siliceous shale, black carbonaceous mudstone, sandstone and chert; radiolarian faunas provided a convincing latest Permian age for both sections.…”

“…They described the rocks as siliceous shale, black carbonaceous mudstone, sandstone and chert; radiolarian faunas provided a convincing latest Permian age for both sections. What is thought to be Section II of Sashida et al (2000b) has been examined by the present author (who determined its location from GPS as 12°51.02 0 N, 101°37.00 0 E) and it is considered to be the same section as that described by Geard (2008), who gave these rocks the name Yaang Formation, stating that it consists of about 20 m of alternating mudstone, siltstone, possibly tuffaceous sandstone with planar and convolute lamination, and black carbonaceous mudstone; she described chert as only a minor component. Geard (2008) analysed detrital zircon grains from a sandstone sample and found a range of ages (600 Ma, 430 Ma, 352 ± 3 Ma) implying that the rock is of Early Carboniferous age or younger.…”

Radiolarian evolution during the latest Permian in South China

“…New genera highly resemble some Mesozoic genera in outline, but their inner structures may put them into the Order Entactinaria. For example, Megaporus is very similar to some genera of subfamily Pantanelliinae Pessagno in morphology (Feng et al, in press-a), and Klaengspongus Sashida is similar to Orbiculiforma Pessagno in morphology (Feng et al, 2000;Sashida et al, 2000b;Feng and Gu, 2002).…”