Microbialite consists of a lower thrombolite (1.5 m thick) and an upper dendrolite (0.5 m thick). Hindeodus parvus conodont is present. the putative keratose sponge consortia were identified
from a thin-bedded, spar-cemented oolitic limestone below the basal microbialite unit. It overlies unconformably above the uppermost Changhsingian bioclastic limestone. Above this oolitic limestone layer, the thrombolite is characterized by a clotted texture of reddish sparitic patches embedded in a grey micritic matrix, whereas the overlying dendrolite texture consists of brownish sparitic patches embedded within a yellow micritic matrix (weathering colour). Several shell layers containing microgastropod and bivalve fragments, ostracod tests, and intraclasts occur above the microbialite unit (Fig. 2). Above these shell layers is the succession dominated by micrites interbedded with peloidal wackestones. In the oolitic limestone layer, single ooids are 0.2–0.6 mm in diameter and round to oval in outline, occupying 55–65% of entire petrologic texture, and they are unevenly distributed. These ooids are strongly micritized so that concentric lines or radial structures become vague. Some grains retain outline of bioclast remains, mostly gastropods. The pores between the ooids are normally cemented by sparites and micritic clumps (micrite aggregates) are interspersed occasionally, indicating an intermittent high-energy environment. Light-coloured sparitic structures are rather common and evenly scattered and almost fill the dark-coloured micritic clumps. Some elongated individuals show vermiform shapes, while others are filamentous and branch occasionally. These dot-shaped and filamentous structures form maze-like networks. Single filaments vary in length, ranging from 100 to 500 μm, while their thicknesses are relatively consistent, except for tapering ends. Individual filaments are 10–70 μm (averagely 33 μm) in diameter, with filaments of 20–30 μm in diameter being most frequently occurring (nearly 20%). About 60% filaments are 20–40 μm in diameter. Filament is slightly inflated at the junction when branching, and these filamentous sparitic structures tend to be distributed parallel to the edge of the micritic clumps.