Tolu Minerals Ltd (ASX:TOK) has started a program of airborne mobile Magneto Telluric (MT) surveys over its Papua New Guinea portfolio of gold, silver and base metal mineralised projects with the Tolukuma Mining Lease the first target.
The objective of the airborne MT geophysical surveys flown by Expert Geophysics Limited (EGL) is to provide electrical resistivity imaging to a depth below surface of 1 kilometre.
Complementary VLF data will provide near-surface conductivity information to define geological structures related to gold, silver and base metal mineralisation, as well as magnetic data to help map geology.
Tolukuma first location
The Tolukuma survey will cover approximately 2,500 square kilometres and will be followed by a survey covering around 200 square kilometres over the Ipi River EL2780 northwest of Tolukuma with both to have a flight line spacing of 200 metres.
After completing the surveys over the PNG mainland projects, EGL will move to the gold and polymetallic copper-lead-zinc sulphide system at Mt Penck EL 2662 on New Britain covering 185 square kilometres with north-south flight line spacings of 200 metres.
Evolving exploration strategy
Tolu Minerals managing director and CEO Iain Macpherson said: “It is pleasing that we have commenced the Airborne MT geophysical survey over our portfolio of gold, silver and base metal mineralised projects, initially centred around the Tolukuma Gold Mine.
"The survey will not only help define a new generation of gold and copper targets related to both existing and new structures including deeper porphyry copper-gold systems in the region but will also inform on an evolving exploration strategy.
"We look forward to providing further updates as preliminary data becomes available.”
Tolu Minerals Ltd project locations.
Program aims
The airborne MT program is expected to take place over the next three months and will greatly assist in identifying a new generation of geophysical targets to complement historical work related to gold and copper-lead-zinc mineralisation for ground follow-up and drill testing.
Results will enhance the company’s existing extensive database of technical information including airborne and ground geophysics, geochemistry, historical drilling results and geology.
Resistivity data from the airborne MT, which has already been used with good success at K92 in PNG, will be modelled to help provide a more accurate guide to depth and location of drill targets.
New targets
Tolu expects to be able to interpret new targets that will require an ongoing field exploration program of geological mapping, sampling and drill testing following on from its current drill program at the Taula prospect.
Mobile MT utilises naturally occurring electromagnetic fields from three orthogonal induction coils contained within an aerodynamic-shaped capsule towed by helicopter 60 to 70 metres above the ground.
In addition, magnetic data will be collected to assist in mapping sub-surface geology.