Linking hinterland evolution and continental basin sedimentation by using detrital zircon thermochronology: a study of the Khorat Plateau Basin, eastern Thailand

Abstract

The effectiveness of detrital zircon thermochronology as a means of linking hinterland evolution and continental basin sedimentation studies is assessed by using Mesozoic continental sediments from the poorly understood Khorat Plateau Basin in eastern Thailand. New uranium lead (U‐Pb) and fission‐track (FT) zircon data from the Phu Kradung Formation identify age modes at 141 ± 17 and 210 ± 24 Ma (FT) and 2456 ± 4, 2001 ± 4, 251 ± 3, and 168 ± 2 Ma (U‐Pb), which are closely similar to data from the overlying formations. The FT data record post‐metamorphic cooling, whereas the U‐Pb data record zircon growth events in the hinterland. Comparison is made between detrital zircon U‐Pb data from ancient and modern sources across Southeast Asia. The inherent stability of the zircon U‐Pb system means that 250 Myr of post‐orogenic sedimentary recycling fails to change the regional zircon U‐Pb age signature and this precludes use of the U‐Pb approach alone for providing unique provenance information. Although the U‐Pb zircon results are consistent with (but not uniquely diagnostic of) the Qinling Orogenic Belt as the original source terrane for the Khorat Plateau Basin sediments, the zircon FT cooling data are more useful as they provide the key temporal link between basin and hinterland. The youngest zircon FT modes from the Khorat sequence range between 114 ± 6 (Phra Wihan Formation) and 141 ± 17 Ma (Phu Kradung Formation) that correspond to a Late Jurassic/Early Cretaceous reactivation event, which affected the Qinling Belt and adjacent foreland basins. The mechanism for regional Early Cretaceous erosion is identified as Cretaceous collision between the Lhasa Block and Eurasia. Thus, the Khorat Plateau Basin sediments might have originated from a reactivation event that affected a mature hinterland and not an active orogenic belt as postulated in previous models.

Shark faunas from the Late Jurassic—Early Cretaceous of northeastern Thailand

“…The detrital zircon thermochronology study conducted by Carter and Bristow (2003) suggested an Early Cretaceous age for the Phu Kradung Formation, but they also identified a Late Jurassic zircon source in their samples. The latter were collected near Phakdi Chumphon, in the western part of Chaiyaphum province, at least 300 km away from any of the sites that have yielded vertebrate microremains, in the more southern part of the Khorat Plateau.…”

“…Its thickness varies from 1,200 m in the basin centre to around 500 m on its southern flanks (Racey 2009). It consists of fluvial sandstones, siltstones and mudstones, and is dated as either Late Jurassic based on fossil vertebrate evidence (Buffetaut et al 2001;Buffetaut and Suteethorn 2007;Tong et al 2009a) or Early Cretaceous on the basis of palynology (Racey and Goodall 2009) and detrital zircon thermochronology (Carter and Bristow 2003). The Formation can be divided into a lower and an upper part, with sandstones tending to be more common in the upper than in the lower part (Sattayarak 1983;Racey et al 1996).…”

Zircon U-Pb geochronology and heavy mineral composition constraints on the provenance of the middle Miocene deep-water reservoir sedimentary rocks in the Yinggehai-Song Hong Basin, South China Sea

“…8), with two major Wang et al (2011), Wen (2013 and Wen et al (2013). Data for Indochina Block are from Carter and Moss (1999), Carter et al (2001), Carter and Bristow (2003), Roger et al (2007), Liu et al (2012) and Kamvong et al (2014). Data for Red River are from and Hoang et al (2009).…”

Runoff Processes in Southeast Asia: Role of Soil, Regolith, and Rock Type

“…6). The presence of these less-permeable soils may be the result of the less-permeable evaporite upper strata of underlying rock that form the parent material (Carter and Bristow 2003). This observation would also support the idea that the Mae Nam Mun River system is hydrologically isolated from the deep aquifer beneath the Khorat Plateau.…”