Combined partial relinquishment report for EL 22478 Roper 1, EL 22479 Roper 2, and EL 22480 Roper 3, period 10 August 2001 to 09 August 2004

Abstract

Exploration Licences 22478, 22479 and 22480 were granted on 10 th August 2001 to Mr G Fanning under an Agreement with Exploration & Resource Development Pty Ltd (ERD), a Darwin based resource sector company. ERD Pty Ltd is the designated Project Manager. A 12 month waiver of the 50% relinquishment due at completion of tenure year 2 (9th August 2003) was requested and accepted by the NT Department of Business, Industry & Development (DBIRD) with effect 8th July 2003. Following rationalisation of tenure holding, 215 sub-blocks (EL 22478), 238 sub-blocks (EL 22479) and 221 sub-blocks (EL 22480) were submitted for relinquishment to DBIRD on 1st July 2004. The relinquished portions of EL 22478, 22479 and 22480 cover approximately 2,230 sq km of parts of Roper Group stratigraphy in the Bauhinia Shelf and Arnhem Shelf tectonic elements of the western McArthur Basin. Tenement acquisition was based on perceived prospectivity for heavy minerals (HM) liberated from eroded dolerite sills which intrude the Roper Group sediments at various stratigraphic horizons. Exploration activities within the relinquished portions included: . Reconnaissance phase helicopter-supported collection of shallow soil and surficial lag samples at two mapped dolerite localities in northern EL 22478, 2 localities in the western portion of EL 22479 and 4 localities in the northeast of EL 22480. The soil samples reported 2% to 16% heavy mineral panned concentrates while the selective lag samples returned 3% to 43% concentrates. All cons were dominated by titanomagnetite assemblages. The targeted regolithic soils were thin, dominantly apron terraces to relatively fresh dolerite subcrop. A series of small backhoe excavations to one metre depths further testing dolerite regolith targets was completed with collection of representative 15 kg channel samples from the pit walls, cumulating in 35 samples from EL 22478 and 8 samples from EL 22479. Low tenor heavy mineral concentrates report from all of the samples. An extensive alluvial plain to the north of a large curvilinear mapped dolerite body on the western portion of EL 22479 was tested for transported heavy minerals with auger drill traversing over a 16 km EW baseline and 500 m NS cross lines with 200 m hole spacings. 473 holes were drilled for a cumulative 1,669 metres. Clay-rich soils with very fine HM were invariably encountered on bedrock of fine-grained sediments. 1,296 samples were processed with an average of 0.47%HM reporting. The sedimentation is considered to be dominatedby an excessive clay component with little evidence of palaeochannels. The low tenor of results reporting from the soil, lag, auger and trench sampling has downgraded the heavy mineral potential of the areas of investigation culminating in 50% reduction of EL tenure.