Annual report for EL 26710 Booda Creek for the period ending 23 October 2010

Abstract

This report describes exploration activities for EL 26710 during the second year of tenure. This tenement is located 114km north-northeast of Tennant Creek. The Booda Bore prospect is located on the eastern edge of the Palaeoproterozoic Tomkinson Creek Group, a dominantly arenaceous sequence. This stratigraphy is overlain by undeformed Middle Cambrian marine sedimentary rocks that comprise the western edge of the Georgina Basin. Early Cambrian deposition is represented by the Helen Springs Volcanics that consist of amygdaloidal tholeiitic basalt and a basal sandstone unit. The Middle Cambrian Gum Ridge Formation was deposited in shallow shelf epicontinental seas subject to episodic peritidal influence. Lithologies consist principally of limestone with minor, but important, phosphate units. Research showed the presence of several water bores with strong phosphate indications within EL 26710 and basement highs and embayments are interpreted from airborne magnetic data. These features are considered to favour phosphorite accumulation. The target stratigraphy is flat-lying to gently dipping such that any near-surface phosphorite is expected to display elevated P, U and other elements that could be identified by geochemical sampling. Three soil sample traverses were conducted over the embayment described above. Widespaced soil P assays define an extensive zone with six samples assaying >100ppm P with U(2)/Th ratios in the range 0.05-0.1. Old drill cuttings from Gum Bore assayed 1050ppm P with a U(2)/Th ratio of 0.55. The geochemical data confirm the presence of phosphorite, not only in the sub-surface but over 35km long by 10km wide northwest-trending embayment constituting Areas of Interest 1 and 2. It is flanked on both sides by a series of magnetic highs interpreted to reflect near-surface basalt of the Helen Springs Volcanics. The central part of the embayment appears downwarped possibly due to a regional structural discontinuity. The SW flank (Area of Interest 3) is about 25km long within the tenement and remains untested because of unsuitable track access. Further soil sampling and RC drilling have been recommended.