Today is

 

 

GEOLOGICAL AND STRUCTURAL SETTING OF THE
MUHONG ORE BODIES IN BASAY, NEGROS ORIENTAL

Romel P. Jacinto
William C. Holifena
 

 

 

 

ABSTRACT



The prophyry copper deposits of Muhong lie near the southeastern end of a mineralized belt in Southwestern Negros that extends approximately 55 kilometers along a northwesterly trend. Presently, there are three known deposits: (1) the Northwest, (2) Central and (3) Southeast orebodies. Host rocks to mineralization at Muhong are volcanic flows and pyroclastics of intermediate to acidic composition and quartz diorite stocks.

Copper mineralization consists mainly of chalcopyrite occurring as dissemination: and fracture fillings commonly associated with quartz veining. Where supergene enrichment has developed, most of the primary chalcopyrite is altered to digenite. Molybdenite is constantly discernible within the ore zones although usually much less erratic concentrations confined mostly along fractures and highly silicified sections.

Hydrothermal alteration is well represented by varying degrees of chloritization, argillization, silicification and mica development in the vicinity of the orebodies. Major structures that control the Muhong orebodies are pair of steeply dipping parallel first-order faults trending
northwest. Outside the zone bounded by these faults, ore mineralization terminates abruptly. The close similarity in the mineralogy, alteration and proximity of the deposits suggest the strong possibility of their being originally one continuous body. Subsequent second-order faults trending northeast and north-south caused lateral as well as vertical displacements in the ore mass imparting to it its present configuration.
 

 

 

 

Geological Society of the Philippines

Unit 250, 2nd Floor, Cityland Pioneer, 128 Pioneer Street, Mandaluyong City, Philippines

Tel: +(63-2) 633-9025