The Manbarrum Project is located within the Northern Territory, 25 km east of Boab’s flagship Sorby Hills Project. Boab acquired 100% of the Manbarrum Project including associated mining leases, mining lease applications, exploration licences, and mining information from Todd River Resources in July 2021.
- Mineral Resources declared at two prospects (Sandy Creek and Djibitgun) within the Manbarrum project area.
- 175km2 of prospective tenements (including two granted mining leases) covering geology genetically related to that found at Sorby Hills will allow for an effective transfer of technical knowledge to maximise exploration and Resource development potential at Manbarrum.
- Conceptual open pit mining studies completed by CSA Global in 2018 delivered positive results based on an on-site processing facility and identified the opportunity to improve project economics via toll treating at a future plant located at Sorby Hills.
The Company will concurrently investigate how the Manbarrum Project may incorporate into Boab’s broader regional production strategy.
Map 1. Manbarrum Project Area relative to the Sorby Hills Project
Zinc-dominated mineralisation has been discovered and delineated by drilling within the Manbarrum Project at two locations, Sandy Creek and Djibitgun. Both occurrences are located along the eastern margin of the onshore Bonaparte Basin (Burt Range Sub-basin) with Sorby Hills being the geographical counterpart on the western margin of the sub-basin. Both mineralisation districts are part of the Late Devonian – Early Carboniferous metallogenic Mississippi Valley Type (“MVT”) mineral system.
Map 2: Regional geology of the Bonaparte Basin
Map 3: Cross-section of the Burt Range sub-basin geology showing the stratigraphic relationship between the Manbarrum Project and Sorby Hills
The Manbarrum Project includes the Sandy Creek zinc-dominated Mineral Resource which previous owner Todd River Resources explored between 2006 and 2009 under the direction of Boab’s current exploration manager.
Mineralisation at Sandy Creek consists of a large tabular horizon of mineralisation in sandy carbonate rocks immediately below a regional shale horizon (Milligans Formation) and secondly, mineralisation in steeply-dipping, high grade fissure zones which in the past have resulted in exceptional intercepts.
The Boab technical team is of the view that these high-grade zones present very attractive exploration targets and future work will leverage exploration knowledge gained from the Sorby Hills deposit to refine the Sandy Creek geological model with a view to increasing the Resource size and grade with subsequent drilling programs.
A JORC 2012 resource has previously been reported on the Manbarrum Project. To date Boab has not undertaken independent verification of the resource and will not be able to publicly report it until and subject to, Boab undertaking its own assessment of the resource and underlying exploration results.
“Mississippi Valley-type” mineralisation also referred to as carbonate-hosted zinc-lead (silver) mineralisation is globally known to form mineral districts hosting 10’s to 100’s of millions of tonnes of base metal mineralisation. Global exploration has shown that most MVT districts include multiple deposits ranging in size from 0.5 Mt to 10 Mt located along the periphery of a basin. The smaller Burt Range Sub-basin within the Bonaparte Basin is analogous to global MVT districts in terms of size, source of metals, pathways for the expulsion of mineralisation and trap sites for mineralisation.
This view is supported by seismic data that is interpreted to show in excess of 4 km of source rock sediments accumulated in the basin from which the metals that form the mineralisation could have derived. The integration of seismic data from petroleum exploration into the mineral exploration in the region has not been attempted before in this area and will provide an additional tool to guide exploration. Boab’s exploration team takes the view that the Burt Range Sub-basin is highly prospective for MVT deposits has the significant exploration potential remaining.
Over the mid to long term, Boab is planning to implement an exploration strategy that is aimed at:
- integrating all technical data into a basin-wide exploration model,
- defining priority target areas within and outside the land holding for targeting or acquisition,
- assessing the untested geochemical, geophysical and structural geological anomalies inherent in the Manbarrum Project data set,
- carrying out a synthesis of mineralisation settings across the sub-basin,
- reviewing the scope for re-interpretation and targeting of the high-grade mineralisation at Sandy Creek and Djibitgun,
There are multiple Zn-Pb-Ag soil anomalies located along the eastern basin margin, coincident with faults mapped from seismic and gravity data that have yet to be drill tested. Furthermore, the synthesis of IP anomalies, gravity and geochemistry anomalies throughout the project area will aid the interpretation of ore-fluid trap locations for future investigation.