This study is guided by a thread of thought which can be stated as fol lows: first, the geological environment and factors governing ore-formation are transformed into geochemical environment and factors; then, the ore-control ling geochemical environmental factors are transformed into indicators for geochemical exploration. The siderite-Pb, Ag and Zn deposti.s of the Zhashui-Shanyang metallogenic belt in southern Shaanxi have proved to be formed mainly by syngenctic sedimentation from a submarine hot brine and control led by relatively sealed depressions on the sea floor and by syngenetic faults. At the geological reconnaissance stage, however, it is difficult to find syngene-tic faults and depressions on the sea floor by geological observation. In order to solve this problem, we consider that, instead of the geological factors, the geochemica! environmental indicators, i. e., high boron and barium contents of argillaceous rocks reflecting high salinity of hot brines, can be used to indica te favorable ore-forming areas. A comparison of boron and barium contents of argillaceous rocks from the ore-containing strata near and far from the ore depo sit has confirmed this supposition. Boron-metiric survey and barium-metric survey were carried out at the Heigou ore district, and the result shows that large distinct boron and barium anomalies are coincident perfectly with the known ore bed. This proves that the distribution of boron and barium in the sedimentary strata not only reflects well the high salinity environment for syngenetic sedimentary ore-formation, but a’so serves as an effective indicator in prospecting for this type of stratabound deposits.