Characteristics and quantitative evaluation of volcanic effective reservoirs: A case study from Junggar Basin, China

摘要: Abstract The Permian Jiamuhe Formation in Jinlong-2 Block is an unconventional volcanic reservoir that has been a major target of oil production the northwest margin Junggar Basin, China. This study focuses on analyses geological, well-logging and data to understand characteristics set up quantitative evaluation method reservoirs. geological reveals lithology mainly includes andesitic (welded) breccia, andesitic/basaltic brecciated lava andesite. space composed stomata dissolution pore, followed by intercrystalline pore intergranular therefore characterized low medium porosity (ϕ) ultra-low permeability (k). mercury injection capillary pressure curves have shown microscopic throat effective reservoirs express fine type with unimodal coarse state, partial state bimodal state. Moreover, limits (ϕ ≥ 8%, k ≥ 0.03 × 10-3μm2) determined test cross plot resistivity. Thus, based analysis macroscopic characteristics, we optimize K-means clustering typical Fisher's discriminant classification criteria functions, which divide into 3 classes accordingly. Our results applied development area, average daily deployed horizontal wells 204 bbl/d, cumulative for one year 68 Mbbl. may provide strong technical supports efficient reservoir.