Abstract:

Abstract: Marine carbonate reservoirs in Tarim Basin are regarded as an important domain for reserve growth and production addition. However, the previous sequence stratigraphic division of the Lower Paleozoic carbonates is not suitable for target selection and development strategy optimization, influencing production. According to the genesis (such as tectonic, exposure and erosion, diagenetic intensity) of the sequence boundaries, and combining with data such as outcrop observations, seismic profiles, logging curves and core analysis of the marine carbonates in Tarim Basin, we recognized five types of marine carbonate sequence boundaries, including TypeⅠ (karsttype boundary from late strong uplifting), TypeⅡ (microkarst type boundary from early forced regression and erosion), Type Ⅲ (platformmargin type boundary from early dissolution and weak erosion), Type Ⅳ (shallow reefbank type boundary from penecontemporaneous intermittent exposure), and Type Ⅴ (contemporary underwater carbonate platform type boundary). Although the genesis and reservoir characteristics of these sequence boundaries are quite different, they can be easily distinguished according seismic, logging, drilling and core data. This division scheme is pracitical and can be used to guide selection of favorable plays, identification of sweet spots and selection of development well types.

Key words:  , Key words： sequence boundary, Cambrian, Ordovician, Lower Paleozoic, carbonate rock, Tarim Basin