Detrital composition and sedimentary provenance of Early Carboniferous Al-bearing rock series in central Guizhou

Abstract

The Early Carboniferous Al-bearing rock series in central Guizhou is an important bauxite ore-bearing and Li-rich stratigraphic unit. The origin and correlation of detrital zircon ages from different types of Al-bearing rock series will provide new insights into the sedimentary processes and metallogenic mechanisms. We present the detrital zircon U-Pb ages and Hf isotopic compositions from the Early Carboniferous Al-bearing rock series and underlying Ordovician clastic rocks (Tongzi and Meitan Formation). The early Carboniferous Al-bearing rock series in the central Guizhou show two dominant age peaks at ca. 980–960 Ma and 540–530 Ma and several subordinate age peaks (ca. 2500 Ma, 820–780 Ma, and 630–610 Ma). The deposition of the Al-bearing rock series occurred near the direct source and the provenance of the Jiujialu Formation mainly originated from the recycled sedimentary bedrock of underlying Ordovician stratigraphic units. Most recycled clastic materials of the Early Carboniferous Al-bearing rock series originated from external sources outside the South China Block. Ferrous clay rocks and Aluminous clay rocks show two age peaks at ca. 540 Ma and 970 Ma. Detrital zircon from the bauxite diposits shows multiple detrital age peaks, reflecting the supply of multiple provenances. Aluminous or Ferrous clay rocks are more widespread in the southern segment of central Guizhou may be related to the early carboniferous transgression.