Lundin Gold’s exploration is focused on the Suarez pull-apart basin, the structure that hosts the Fruta del Norte gold deposit. The ideal ore-forming conditions that formed Fruta del Norte are interpreted to occur elsewhere within this structure. Lundin Gold has brought together most of the original Aurelian Resources exploration team that discovered Fruta del Norte.
In early 2006, Fruta del Norte was discovered after the Suarez pull-apart basin was re-interpreted as syn to post-mineralisation. The observation of silicification, epithermal textures and geochemistry at Fruta del Norte led to the successful drill intersection of the gold-silver deposit buried beneath basin fill sediments.
The Suarez pull-apart basin was believed to extend approximately 8 km to the south of the Fruta del Norte deposit and be about 2 km in width. Exploration drilling in 2016, followed by mapping in 2017, located basin fill sediments and extensive late andesite cover rocks (the Fruta andesites) south of the basin, leading to the extension of the Suarez pull-apart basin to approximately 16 km long by 2 km wide.
The El Puma, Barbasco, Rio Negra and Alejandro targets are all areas of altered basin sediment, anomalous in the epithermal pathfinder elements arsenic and antimony with marcasite (with or without illite) alteration, like the sediments around the Fruta del Norte system. Soil and rock sample geochemistry combined with geological mapping are the key tools used for target definition and prioritization. The Fruta del Norte South-West target is unique in that it is based purely on a structural interpretation - that part of the Fruta del Norte deposit has been offset by the West fault and displaced along strike to the southwest.
Geophysics in progress or completed includes a helicopter Z-Tipper Axis Electromagnetic resistivity geophysical survey of the Suarez pull-apart basin, a heli-magnetic and radiometric survey and ground IP (Gradient Array and Pole – Dipole) over selected targets.
The Company has 70,000 ha of exploration concessions that can be divided into the following exploration target types:
1. Buried epithermal gold-silver, Fruta del Norte-style systems that are within the Suarez pull-apart basin. These targets include:
- El Puma
- Rio Negra
- Fruta del Norte South-West
- Fruta del Norte East
2. Buried epithermal gold-silver deposits that are outside of the Suarez pull-apart basin. The targets are interpreted to be related to post-Basin diatreme activity (associated with the Chinapintza diatreme south of the main project area). These targets include:
- Gata Salvaje
- Emperador area (includes the Emperador, Robles, Chanchito and El Arco targets)
3. Porphyry copper (with or without gold and molybdenum) (with or without skarn) systems. These targets include:
4. Other targets including:
- Bella Vista and Pavo Salvaje (batholith hosted gold veins and shear zones)
- Maicu concessions (potential for skarn and porphyry systems)
Geochemical sampling and mapping to define drill targets has been completed over many of these targets and is ongoing on others. Drilling has been focused on Fruta del Norte, with some historic drilling at Puente-Princesa (2004), Alejandro (2005 and 2006), Fruta del Norte East (2008) and Emperador (2016). Drilling began at the El Puma target in November 2017.