1985 Volume 35 Issue 190 Pages 161-177
Pyrometasomatic lead and zinc deposits of the Nakatatsu mine are embedded in skarn zones replacing the Fujikuradani Formation of the Paleozoic age.
The Nakayama skarn zone, located in the eastern portion of the mine area, is classified into hedenbergite zone, garnet zone and clinopyroxene-garnet zone. Despite changeful thickness of each zone, individual zone can be traced continuously in both lateral and vertical directions. They dip and strike concordantly with general structure of the Fujikuradani Formation.
The Nakayama ore deposit consists of many massive and bedded ore bodies. Most of them are localized in the hedenbergite zone. Especially rich ore bodies are developed in the hedenbergite zones adjacent to intercalated thin layers of slate and diabase. The shape of the ore bodies is also controlled by the structure of the thin layers.
These facts indicate that the mineralization of the Nakayama ore deposit was controlled by structure and mineral composition of the skarn, and that each ore body occurs to be controlled by presence and structure of the thin layers in the skarn zone.
Based on the conclusion of the studies, recent systematic exploration activities carried out in the Nakayama skarn zone have resulted in the significant discovery of several new ore bodies.
