Globigerinid limestone in Gas Field A of Madura Strait in Indonesia might be deposited by bottom current in outer shelf to upper slope.Petrological and reservoir space characteristics as well as well logging and seismic data were integrated to describe its sedimentary characteristics.According to Dunham's classification

the reservoir consists of grainstone

packstone and wackestone.The former two lithologies are grain supported and well sorted

and the reservoir space was dominated by intragranular dissolved pore

followed by intergranular dissolved pore and vuggsand a small amount of moldic pores and fractures.The reservoirs feature in large thickness

good physical properties and high NTG

and have great petroleum-bearing potential.There has been much debate over the depositional environment of the Pliocene globigerinid limestone in the Madura Strait.We propose three provenances for the reservoir.