Devonian fluviodeltaic sedimentation in Hong Kong

U-Pb detrital zircon geochronology of sedimentary rocks in NE Vietnam: Implication for Early and Middle Devoni-an Palaeogeography

“…Based on the collected LepidodendropsisBothriolepis assemblage, the Van Huong Formation was considered to be Middle Devonian (Givetian, see Long et al, 1990) in age, and overlying massive sandstones may also extend into the early Late Devonian (Janvier et al, 2003). The overall sedimentary record mainly represents fluvial to deltaic prograding deposits close to a shoreline and are very similar to deposits of the same age known from South China (Xun et al, 1996;Jones et al, 1997). The Devonian red-coloured sediments are found in the Hue area while marine sediments of the same age are found in the west, in the center of the Red River Basin.…”

“…Depositional facies settings of Late and Middle Devonian siliciclastics in NE Vietnam are comparable to those along the southeastern coast of China (e.g. Jones et al, 1997) and they also yield the same vertebrate remains (Yang et al, 1981;Lee, 1991;Jones et al, 1997;Janvier et al, 2003). In this paper, we present U-Pb detrital zircon ages of siliciclastic rocks from two formations in NE Vietnam and discuss the results with paleo(bio)geographic affinities and derivations of Devonian siliciclastics in southern China.…”

“…Similar facies settings are known from northeast Vietnam. The assumed palaeogeographic position of NE Vietnam in the Early and Middle Devonian close to the western Himalayas is most likely due to faunal similarities between Vietnam and southern China (Janvier and Ta Hoa, 1999;Janvier and Tong-Dzuy, 1988;Jones et al 1997). Based on vertebrates, ostracods, and brachiopods there is likely a palaeobiogeographic relation between the East Red River region in Vietnam and southern China.…”

Middle Jurassic collision of an exotic microcontinental fragment: Implications for magmatism across the Southeast China continental margin

“…15°) and generally non-metamorphosed. Devonian rocks NW of the TCF contain an Early to Middle Devonian flora and marine fauna, and show paleocurrent directions toward the northwest (Jones et al, 1997). In contrast, Devonian rocks to the south have a Late Devonian flora and show paleocurrent directions toward the southeast (Jones et al, 1997).…”

“…Devonian rocks NW of the TCF contain an Early to Middle Devonian flora and marine fauna, and show paleocurrent directions toward the northwest (Jones et al, 1997). In contrast, Devonian rocks to the south have a Late Devonian flora and show paleocurrent directions toward the southeast (Jones et al, 1997). Jurassic sandstones and shales north of the TCF have an Early to Middle Jurassic terrestrial flora and marine fauna , whereas Jurassic sandstones and shales south of the TCF are exclusively marine .…”