Geological Survey of Tanzania (GST)
Geophysical Investigation — Handeni District, Tanga Region
An Induced Polarization (IP) and resistivity survey by the Geological Survey of Tanzania to identify subsurface structures controlling copper mineralization.
Purpose & Scope
The Geological Survey of Tanzania was contracted by Dharti Minerals Company Limited to undertake a geophysical survey using the Induced Polarization (IP) and resistivity method, in order to depict any subsurface structures that might be controlling copper mineralization.
The work involved gathering and reviewing published geoscientific reports on the concession area. The information obtained was used to plan the fieldwork: thirty-four (34) profile lines, surveyed with a dipole–dipole configuration at a 10 m electrode interval, together with geological mapping of lithological units and structures and their relationship with copper mineralization.
Geology of the Area
The concession area is mainly dominated by garnetiferous hornblende gneiss, particularly in the southern part of the area. The northern part, especially near the Msangazi River, is covered by superficial soil.
The lithological units are well exposed on the surface, widely dispersed and cross-cut by quartz veins trending east–west.
Key Findings
The ground geophysical survey showed variation of resistivity and chargeability along the surveyed profile lines. Areas with high resistivity were demarcated as anomalous zones, occupied by outcrops of garnetiferous hornblende gneiss.
The copper mineralization is associated with the mineral garnet, and is probably hosted and controlled in quartz-vein-filled structures within the garnetiferous hornblende gneiss.
Recommended Further Exploration
Further exploration work on the demarcated zones is recommended to reveal potential quartz-vein-filled structures hosting copper mineralization: