There occur high-salinity belts of oil-field water in areas of oil-migrating faults, i. e. contemporaneous faults connecting source rocks and nor.source rocks, in the Dongying and Huimin basins. There belts are not only consistent with the distribution of known oil and gas pools but there appears positive correlation between the anomalous salinity of water and petroleum reserves. Take the Dongxin, Xianhezhuang and Linshang oil fields for example, the paper analyses the genetic relation and association between the oil-field water and the formation of oil and gas pools. The geological reserves of petroleum in a new prospect area of the basin has been quantitatively predicted by the correlation curves and, which have been confirmed by drilling.