Microsoft Word - RNI 23-12-15 Bryah Basin Drilling Update (Final for Lodgement).docx
ASX Announcement 23 December 2015
BRYAH BASIN DRILLING UPDATE
KEY POINTS
-
Drilling across key target areas at RNI's Doolgunna and Morck's Well copper-gold projects in WA's Bryah Basin has successfully defined stratigraphic and alteration characteristics typical of volcanic hosted massive sulphide (VHMS) deposits similar to DeGrussa
-
Significant horizons identified at the Cuba, Jerry's and Citra prospects showing exhalative units, alteration, mafic volcanics and interspersed sedimentary packages
-
Initial assay results from first drilling phase expected in January 2016
-
Assay results and geological analysis will define targeted follow-up drilling programs and geophysical surveys
-
Aircore drilling will continue in January 2016 with planned 205-hole program at the Forrest Project and the priority Big Red VHMS target at Morck's Well
RNI NL (ASX: RNI) is pleased to announce the successful completion of the first phase of the Company's systematic drilling and exploration program in Western Australia's Bryah Basin.
The first phase involved reverse circulation (RC) and aircore drilling at the Cuba, Jerry's, Marty's Patch and Maguire targets within RNI's Doolgunna Project (Figures 1 and 2), and at the Citra, EM2 and Limestone targets at the Morck's Well Project (Figure 1).
The drilling at Cuba, Jerry's and Citra intersected significant target horizons with exhalative units, alteration, mafic volcanics and interspersed sedimentary packages, which are all consistent with VHMS deposits both globally and within the Bryah Basin, particularly the DeGrussa deposit.
RNI's Doolgunna Project is located approximately 2.5km from DeGrussa (Sandfire Resources) and within 5km along strike from the high-grade Monty copper-gold discovery (Sandfire/Talisman) (Figure 2). The northern boundary of Morck's Well is contiguous with Sandfire's Doolgunna property, which hosts DeGrussa.
Samples from this first phase drilling have been sent for assaying, with initial results anticipated in mid- January 2016. Follow-up down-hole electromagnetic (DHEM) surveys are planned for the Marty's Patch and EM2 prospects (Figure 1) in January 2016.
The assay results, along with the geological analysis and DHEM survey data, will be used to plan targeted follow-up drilling programs scheduled to commence in the first quarter of 2016.
RNI NL ABN 77 085 806 284
34 Bagot Road Subiaco Western Australia 6008 PO Box 298 West Perth WA 6872 T +61 8 9489 9200 F +61 8 9489 9201 E [email protected] W rninl.com.au
In addition, the next phase of aircore drilling will commence in January 2016 with a total of 205 holes planned at the Forrest and Morck's Well Projects. These hole will be drilled at Tempest EM1 (24 holes for 1,140 drilled metres), Tempest EM2 (44 holes for 2,640m), the Forrest-Wodger trend (43 holes for 2,580m) and Big Red (94 holes for 5,640m) (Figure 1). This aircore drilling program is designed to penetrate the transported cover and provide a platform for follow-up drilling and exploration.
Jasperoidal chert and magnetite from the Citra Prospect. Evidence of hydrothermal fluids exhaling onto the seafloor, which is a prime marker horizon for VHMS deposits both globally and within the Bryah Basin
RNI Chief Executive Officer David Morgan said the first phase of Company's systematic RC and aircore drilling and exploration program had provided some highly encouraging initial results.
"While we await the assay results, we are very encouraged by the early indications and promising geology of a number of the prospects drilled. In particular, we are already seeing some very strong geological parallels with the DeGrussa VHMS copper-gold discovery."
"The drilling and pending assay results combined with our knowledge of the Bryah Basin will provide a strong platform on which to build our follow-up programs."
"We look forward to the first quarter of 2016 with much excitement as we continue our aircore program at Forrest and Big Red and plan for the commencement of targeted follow-up drilling later in the first quarter."
Figure 1: RNI's Bryah Basin copper-gold portfolio showing locations of priority prospects being targeted in the current drilling and exploration program at the Doolgunna, Morck's Well and Forrest Projects
The completed first phase of RC and aircore drilling is summarised below.
DOOLGUNNA PROJECT
Cuba Prospect
The aircore program at Cuba involved the drilling of 128 holes for a total of 7,563m. Throughout the program, the drilling encountered dominantly clastic sediments (turbidites and shales), which are common VHMS hosts, with several horizons showing evidence of exhalative units and alteration, specifically jasperoid cherts, magnesian talc, chlorite, albite and hematite alteration. This is very similar stratigraphy and alteration to the DeGrussa copper-gold deposit, which is located approximately 3.5km north-west of Cuba (Figures 1 and 2).
The aircore drilling pattern at Cuba was designed to define the horizon that hosts the off-hole conductor identified in DDH1-9 and has provided a solid platform for the next stage of exploration.
The logging and pending assay results will be analysed in January 2016 and used to design the next stage of exploration and drilling at Cuba. The geology encountered demonstrates a compelling need to follow up the success of the aircore program with further drilling and geophysical work.
Jerry's Prospect
The aircore program at Jerry's has been completed with the drilling of 58 holes for 2,188m. A number of mafic and sediment horizons were encountered, which are indicative of the targeted host horizons and included evidence of exhalative (VHMS forming) units and alteration, specifically jasperoid cherts and chlorite, albite and hematite alteration.
This is considered very promising as it continues to demonstrate that the Central Corridor of the Doolgunna Project (Figure 2) has similar stratigraphy and alteration to the DeGrussa deposit and has potential to host VHMS-style mineralisation.
This aircore program has also demonstrated that the potential VHMS horizons extend beyond the cleared access area and that further work is warranted to define the extent of the target horizons. The logging and pending assay results will be analysed in January 2016 and used to design the next stage of exploration and drilling, which will occur after the necessary clearing permits are obtained for an extended area of exploration.
Figure 2: RNI's Doolgunna Project and proximity to DeGrussa and Monty
Marty's Patch Prospect
A single 250m RC hole was drilled at Marty's Patch to test for the source of a significant geochemical anomaly. The hole initially intersected dominantly shales with quartz veining and some jasperoid cherts before going into a turbidite sequence of alternating shales and coarse clastic units. Below the coarse clastic units the hole intersected a thick coarse green sandstone unit and then more shales. The geology logged included some alteration and jasperoid cherts. The hole was set up for a DHEM survey in early 2016.
Maguire Prospect
Two 120m RC holes were drilled at Maguire to define the source of a gravity anomaly and a broad surface copper-gold geochemical anomaly. The gravity anomaly was confirmed to be a volcanic vent breccia. The implications of the vent breccia need to be reviewed as these volcanic vents are a main source for hydrothermal flow and there is potential for the existence of associated mineralisation on the flanks of the vent. Pending assays, this prospect will be reviewed and re-evaluated before the next stage of exploration is planned.
MORCK'S WELL PROJECT
Citra Prospect
The RC program at Citra involved eight holes for 678m. A number of mafic/volcanic horizons and interbedded sediments were encountered. These are indicative of the targeted host horizons and included chlorite and sulphide alteration providing support for hydrothermal fluids having been present in the area. Hand held field XRF readings on drill chips returned anomalous copper values over thick intervals (including numerous spot readings above 0.1% Cu). While these values are not commercially relevant, they indicate significant Cu-enrichment within the prospect area.