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Title: Joint annual report for the period 03 March 2007 to 02 March 2008 Calvert Hills Project
Title Holder / Company: Legend International Holdings
Report id: CR2008-0127
Tenure: EL25491;  EL25616;  EL25617;  EL22244;  EL22245;  EL22246;  EL22247;  EL22251;  EL22252;  EL22351;  EL23116;  EL23117;  EL23118;  EL23119;  EL23121;  EL23510;  EL23511;  EL23512;  EL23513;  EL23514;  EL23515
Year: 2008
Author: McGoldrick, G
Farrell, N
Abstract: Exploration for diamonds, base metal and phosphate carried out over the Calvert Hills Project during the reporting period included reconnaissance mapping, reverse circulation and diamond drilling, Heavy Mineral Analysis (HMA) stream sampling, geological logging and geochemical analysis of surface rock, drill-core and drilling rock-chip samples. In the reporting year a variety of targets were explored across the Calvert Hills area. As discussed in regional geology, many of the tenements lie within the Merlin diamond field. The exploration program at Abner Range, in particular EL 23514, EL 23118 and Foelsche EL 22245 and EL 23510 used rock chip, stream, loam HMA sampling grids and diamond drilling to target areas of Kimberlitic rock and locate diamond indicator minerals. Historical open file research identified the presence of Proterozoic phosphate within the Selby tenements in EL 22251. The basal unit of the Karns dolomite, overlying the Echo Sandstone, is associated with the phosphate beds and phosphatic stromatolites in the region. Reconnaissance exploration with associated rock chip sampling located these deposits. Independent consultants were commissioned to map and surface sample the outcrops. These were subsequently diamond and RC drilled, with associated assay sampling. In the Selby Region, stream sampling results for copper, lead and zinc from historical open file research draining the Karns Dolomite identified it as a potential lithological target for mineralisation. Several faulting structures had been identified both regionally on the Robinson River 1:250,000 Map Sheet and through local reconnaissance. As such an independent and comprehensive soil and stream sampling program was conducted over a region of outcropping Karns Dolomite in EL 22247, stretching into EL 22251. Initially, stream and loam sampling (ABG004, ABR010-ABR043) was carried out across EL 23118 and EL 23514. This was followed up across EL 23514 by a comprehensive gridded loam sampling program over positive geochemical anomalies. Two-hundred-and-forty-six samples (ABS1-ABS171, ABS173-ABS190, ABS192-ABS211, ABS230-ABS246) were collected and submitted for chemical analysis. Minor rock chip sampling was conducted across the Foelsche tenements, EL 22245 and EL 23510. Twenty-four samples (FOD1-FOD6, FOG1-FOG3, F13.5A-6 - F14-32.5) were collected and submitted for chemical analysis. Soils were collected at surface, sieved to -2mm and samples of 100g to 500g in size were collected in calico bags and were analysed by XRF and for heavy mineral kimberlitic indicators such as chromite-spinel by Diatech. Initial reconnaissance rock chip sampling was undertaken in the Selby region on EL 22251 to enable identification of phosphate. Sixteen samples were taken (SELR1-SELR16) and sent for analysis. IMC was commissioned to undertake geological mapping of the phosphate outcrops known as 'Camp' and 'Eastern' on EL 22251. While doing so they also collected seven rock chip samples (IMC1-IMC7) for chemical analysis. An independent consultant was commissioned to conduct an extensive stream and loam sampling program across the Karns Dolomite on EL 22247 and into EL 22251. 50 Rock Chip Samples (81401-81422; 81427-81433; 81435-81437; 81439-81443; 81445-81458) & 168 Stream Sediment Samples (1007-1033; 1040; 1043-1123; 1127-1145; 1152-1189; 1192- 1194) were collect for analysis. Soils were collected at approx 15 to 30 cm depth, sieved to -2mm and samples of 500g to 1000g in size were collected in calico bags. Samples were analysed by XRF for phosphate as P2O5, U, Cu, Pb, Zn and Ag by ICPMS from the Total acid digest by ALS, Brisbane and Perth. A program of eight diamond drill holes was undertaken at Abner Range and Foelsche, targeting individual magnetic geophysical anomalies (ABDD1-ABDD7 & FODD1) for a total of 315.90 m, with associated geological logging. The Selby drilling exploration program was focussed on EL 22251. The program consisted of 97 Reverse Circulation drill holes (SELRC01-SELRC97) with associated assay sampling, surface and downhole surveying, logging and assaying. This represents a total of 4710 meters of drilling. Drilling targeted the 'Camp' and 'Eastern' phosphatic outcrops at -90 degree dip and completed to blade refusal, to the intersection with the underlying Echo Sandstone or, in the case of SELRC58-SELRC84, until phosphate was intersected. Drill material was collected every metre in a bucket and dumped on the ground in rows of 10. The hole identification number was painted on a dumpy peg and placed at the start of the first row. One Diamond Drill Hole was completed at Selby EL 22251 (SELDD02), some 4.5 kilometers to the southwest of the 'Camp' and 'Eastern' outcrops. The hole was designed to collar higher in the stratigraphic sequence than the outcropping phosphate, in the Karns Dolomite and was drilled to the contact of the Echo Sandstone at 22.5 meters, in order to test the lateral extent of the basal phosphate- bearing bed in the Karns Dolomite. A total of 3334 samples were collected from the Selby Reverse Circulation Drilling for analysis (SED0100-SED3477. Note, this includes: SED0100A-D; SED101A-D; SED132AD; SED133A-D; SED162A-D; SED163A-D; SED164A-D & SED165A-D). One metre samples were collected in regions which were near-surface or obviously phosphatic in order to ensure detail was intercepted where phosphate occurrence was thinner and lensoidal. At depth, four meter riffle split composites were collected for chemical analysis. Samples were analysed by XRF for phosphate as P2O5, U, Cu, Pb, Zn and Ag by ICPMS from the Total acid digest by ALS, Brisbane and Perth.
Date Added: 24-Oct-2013
Appears in Collections:Minerals Exploration Reports (MEX)

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