The Marqua project area, some 400 km east of Alice Springs, is largely obscured by sand cover. The Cambrian Thorntonia Limestone and Late Proterozoic Wonnadinna Dolostone are extensive in the area and are considered to be prospective for stratiform and stratabound base metals deposits. Uramet conducted VTEM surveys in 2007 and geological mapping, sampling and some drilling in 2008.
The NTGS study recommends that “the shale within the medial Thorntonia Limestone should be further investigated as a potential host for stratiform and stratabound base metal mineralisation.” Prospective geology is associated with down dip extensions of the Thorntonia Limestone and Arthur Creek beds in the north-west part of Marqua, Yackah beds in the south-west, and Neoproterozoic red beds in the core of the Field River anticline. Faults are present which, being active during the Alice Springs Orogeny 320 to 360 million years ago, could have acted as suitable feeder faults.
Prospective stratigraphy including the Thorntonia Limestone and Wonnadinna Dolostone extends over 30 km strike length in the northwest Marqua area. Ferruginous vein systems within basement granitic rocks just to the south of Thorntonia Limestone outcrop contain up to 9% Pb. The occurrence of such veins is a good indication that mineralised feeder systems do exist within the project area.
Uramet flew a total of 2,209 line-km of VTEM across prospective horizons in the Marqua area during 2007. The VTEM has proved very useful in tracing the prospective strata under cover. Several newly discovered gossans were found during a reconnaissance field mapping program in 2008.
Magnetic data recorded as part of the VTEM surveys (“helimag”) in the north-west Marqua area defined six bulls eye magnetic anomalies (M1 to M6), which Uramet considers are worthy of further investigation. The Northern Territory Government has advised Uramet that it will co-fund, under its Geophysics and Drilling Collaborations Program, 50% of the cost of a Uramet drillhole to test one of these bulls eye magnetic targets (M1) in the west Marqua area. Uramet considers this target is prospective for base metal and IOCG style mineralisation and plans to drill the hole in the June quarter of 2009.
Five shallow aircore holes were drilled for a total of 130m on base metal targets at Marqua in September 2008. A batch of 47 samples from these holes was dispatched for laboratory analysis for base metals. Evaluation of laboratory analysis results is underway.
URM Price at posting:
4.5¢ Sentiment: LT Buy Disclosure: Held
