Abstract:

Tainan gas field is located at the central sag area of Qaidam Basin，Qinghai province，the field is very high in salinity，which results in very low reservoir resistivity，the reservoir rocks are dominated by thinly interbeded sandstone and mudstone.Because of the limitation of vertical resolution，conventional well logging curve can not really demonstrate the interbeded formation characteristics，which makes hydrocarbon recognition more difficult.The existing method improving vertical resolution of well logging curve is more placed on theory and geological data is lacking，the operability is poor.Sharplite thin bed processing method is presented by Schlumberger aiming at the situation mentioned above，high resolution well logging curve is obtained by integrating high resolution FMI images and conventional well logging curve to carry out reverse processing.The application in Tainan gas field shows the sharplite thin bed processing method can greatly improve the vertical resolution of conventional curves so as to effectively identify hydrocarbon in thin beds.

Key words: interbeded sandstone and mudstone, resolution, resistivity, Sharplite processing, Qaidam Basin