Project status

Field mapping of the Manilla 1:100 000 sheet has been completed. A map and cross-section of this geologically complex and highly mineralised area are being constructed.

Geology

The Manilla 1:100 000 map sheet area lies in the New England region of north-eastern New South Wales. The area is part of the geological province known as the southern New England Orogen. The area consists of Silurian to Carboniferous metasedimentary and metavolcanic rocks, which locally include thrust slices of Cambrian, Ordovician and Silurian serpentinite, limestone and shallow water sandstones. These are intruded by Early Permian and Late Permian to Early Triassic granitoids, and overlain by Late Permian to Cainozoic volcanic rocks and sediments. The regionally extensive Peel Fault traverses the eastern margin of the sheet area.

Detailed geological mapping for the Manilla 1:100 000 sheet area has been completed. This mapping project aims to produce a standard, print on demand geological map of this geologically complex and highly mineralised area.

The mapping project has resulted in many significant changes and enhancements to the understanding of local and regional geology. Highlights include:

• mapping of regional-scale, folded, serpentinite-hosting thrusts
• identification of Ordovician to Silurian thrust slices
• defining the northerly extent of the Wisemans Arm Formation and redefining its lithological content
• recognising the dislocated complexity of the Appleby Syncline
• confirming the presence of the Late Permian Wandsworth Volcanic Group
• recognising internal, concentric zonation within the Attunga Creek Monzogranite
• confirming the bedding-parallel orientation of some major, regional-scale thrusts

Mineral occurrences in the sheet area include significant orogenic gold veins, skarn-type tungsten, molybdenum and copper mineralisation related to the Inlet Monzonite, and minor manganese oxide-rhodonite lenses. Chromite occurrences are found in the serpentinites.

For more information on the mapping please contact the Geological Mapping Team.