ABM RESOURCES NL ABN 58 009 127 020 GROUP ANNUAL REPORT For EXPLORATION LICENCES EL 23926, 23927, 29367 and 29368 GR253/12 BONITA PROJECT From 16 March 2012 to 15 March 2013 Holder ABM Resources NL Operators ABM Resources NL Author J Rohde Date April 2013 Email joe @abmresources.com.au Target Commodity Gold Datum/Zone GDA94/ MGA Zone 53 250,000 mapsheet Mount Theo (SF5208) Mount Peake (SF5305) 100,000 mapsheet Theo (5155) Partricia (5255), Stuholme (5355), Yaloogarrie (5154), Turners Dome (5254), Giles (5354) Distribution: ο NT DME - digital ο Central Land Council digital File: jr63 NTDME Bonita 2012 GR253_12, EL29367_29368_23926_23927
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ABM RESOURCES NL
ABN 58 009 127 020
GROUP
ANNUAL REPORT
For EXPLORATION LICENCES
EL 23926, 23927, 29367 and 29368
GR253/12
BONITA PROJECT
From 16 March 2012 to 15 March 2013
Holder ABM Resources NL Operators ABM Resources NL Author J Rohde Date April 2013 Email joe @abmresources.com.au Target Commodity Gold Datum/Zone GDA94/ MGA Zone 53 250,000 mapsheet Mount Theo (SF5208) Mount Peake (SF5305) 100,000 mapsheet Theo (5155) Partricia (5255), Stuholme (5355), Yaloogarrie
(5154), Turners Dome (5254), Giles (5354)
Distribution: ο NT DME - digital ο Central Land Council digital File: jr63 NTDME Bonita 2012 GR253_12, EL29367_29368_23926_23927
7.0 RECOMMENDATION and CONCLUSIONS...................................................................... 9 8.0 BIBLIOGRAPHY .............................................................................................................. 11 TABLES Table 1 Tenement Details FIGURES Figure 1 Project Location & Tenement Locality 1 :2,000,000 Figure 2 Planned Bonita Survey and actual samples taken over Interpreted Geology. Figure 3 Surface sampling location Plan (both pH & regional survey) at Swampy EL 29368 over
Interpreted Geology. Figure 4 ‘Depth-slice’ image of the 8th band of the Z-component of the 2012 airborne magnetic
(AEM) data at the Bonita Project. Background image is the open file (AEM) data. Figure 5 Part of a conductivity depth images (CDI) section of one of the flight lines over Bonita.
View is to the north-west Figure 6 Swampy prospect location on a) public domain TMI magnetic data (top) and b) on a
‘depth-slice’ of band 14 of the 2012 AEM data (bottom). Figure 7 Part of the cdi section of flight line 4602 over the Swampy magnetic target showing
interpreted thrust fault. Figure 8 Aeromagnetic image over Bonita Survey. Figure 9 Gold response from the Bonita geochemical survey(EL 23926). Figure 10 Contour Image of Au ppm - ME-MS23 Ionic Leach method values (Left) compared to
the image of the Au_ICP21 Fire Assay Result (Right). Figure 11 Aeromagnetic image over Swampy Surveys Figure 12 Schematic map showing the Gold response over the Swampy pH grid (SW_GS1). Figure 13 Gold response from the Swampy pH geochemical survey(EL 29368).
Figure 14 Gold response from the Swampy regional geochemical survey (EL 29368). Figure 15 Schematic map showing the gold response over the regional Swampy grid (SW_GS2). Figure 16 Geophysical interpretation at Bonita (EL 23926) over gold response image. Figure 17 Geophysical interpretation at Swampy Prospect (EL 29368) over gold
response image. PLATES Plate 1 EL 23926, 23927, 29367 and 29368 & Airborne Electro Magnetic Survey Image
1 :100,000 Plate 2 Surface Sample Location Plan at Swampy (EL 29368) & Ionic Leach geochemistry
contour image 1 : 20,000 Plate 2A Surface Sample Location Plan at Bonita (EL 23926) & Ionic Leach geochemistry
contour image 1 : 20,000 DIGITAL APPENDICES FILE DESCRIPTION GR253_12_2013_GA.pdf Group Annual Report 2013 GR253_12_2013_GA_01_Appendix1.pdf Acquisition and Processing Report (Fugro) GR253_12_2013_GA_02_Appendix2.pdf Conductive Plate Modelling Report (Fanthom) GR253_12_2013_GA_03_Appendix3.pdf ABM’s AEM data acquisition & processing Submission
Report to NT Geological Survey GR253_12_2013_GA_04_Appendix4_CD Bonita - Airborne EM Survey Data on EL29368_EL23926
CD Zipped aeromagnetic data in four folders on CD as follows: cdi folder sections folder sections in pdf format
stacks folder conductivity image - depth sections draped on topography in pdf format
disclaimer folder disclaimer in txt formate grids folder dtm folder EM image sections in pdf format
emxbf folder x sections in ers format emzbf folder z sections in ers format time_constant time constant in ers format located_data in dat,des,dfn,gdb format GR253_12_2013_GA_05_Appendix5.pdf ABM’s Deep Penetrating Geochemistry (DPG) field
1. Subject to 2, the tenure holder acknowledges that this Report, including the material,
information and data incorporated in it, has been made under the direction or control of the Northern Territory (the NT) within the meaning of section 176 of the Copyright Act 1968.
2. To the extent that copyright in any material included in this Report is not owned by the NT, the
tenure holder warrants that it has the full legal right and authority to grant, and hereby does grant, to the NT, subject to any confidentiality obligation undertaken by the NT, the right to do (including to authorise any other person to do) any act in the copyright, including to:
• use; • reproduce; • publish; and • communicate in electronic form to the public, such material, including any data and
information included in the material.
3. Without limiting the scope of 1 and 2 ab ove, the tenure holder warrants that all relevant authorisations and consents have been obtained for all acts referred to in 1 and 2 above, to ensure that the doing of any of the acts is not unauthorised within the meaning of section 29(6) of the Copyright Act.
ABM – GR253/12 Bonita, Group Annual Report 16 March 2012 – 15 March 2013 1
1.0 ABSTRACT The ABM Resources NL (ABM), ‘Bonita’ project is located approximately 230 kilometres north-northwest of Alice in the north Arunta Region of the Aileron Province (Figure 1). The project comprises four granted Exploration Licences - EL 29367, 29368, 23926 and 23927. The tenements were granted to ABM, a publicly listed company, in March and April 2012. On 20th August 2012 the amalgamated technical reporting for Bonita was approved and the group reporting ID GR 253/12 assigned. ABM explores the Bonita project for the potential of gold mineralisation. ABM applied for the tenements for their strategic position along strike of the mineralised Reynolds Range corridor, and its interpreted similar geology, as well as for several anomalous total magnetic intensity features like the Swampy magnetic high. Exploration in the first year of tenure consisted of regional desktop studies, including geophysical and geological interpretations which resulted in the planning and completion of an airborne electromagnetic (AEM) survey over two of the tenements in collaboration with the NTGS and two surface sampling programs. The airborne electromagnetic (AEM) survey covering the majority area of EL 23926 and 2 9368 comprised 58 lines for a total of 1,229 line km with a 1,000m line spacing and a line direction of 42 degrees. The nominal terrain clearance was 100m. The AEM survey covering 1,233km² was completed by Fugro Pty Ltd. (Fugro). The survey data was processed by Fugro and Fathom Geophysics Australia Pty Ltd. (Fathom) completed further processing and interpretation work. Fugro and ABM concluded that the AEM survey revealed a previously unidentified regional structure, as well as generally thick transported cover, deep weathering and two north-south trending palaeo channels towards the eastern parts of the tenement holdings. Fathom concluded that no quantifiable anomalies were recognized in their first-pass plate modelling due to the effects of the overburden, which must be removed from these data, before any effective plate modelling can be done. The two surface sampling program areas Swampy and Bonita were selected in the first place to test conceptual targets of the underlying prospective regional magnetic features interpreted from public domain data. A total of 1239 surface samples were collected; 467 samples on EL 23926 and 77 2 samples on EL 29368. In order to create access to the tenement and particular to the geochemical survey areas approximately 40 kilometres of track grading and regrading was completed. At the Swampy prospect (EL29368) the pH survey and the regional soil survey over a magnetic anomaly of 3km in diameter, at the intersection of tectonic scale geological structures produced an anomaly in the 90 – 100 percentile range, covering an area of 7.5km x 2.5km remains open to the south. A second area, 4.5km x 1.5km, is highlighted by gold response in the 80 – 98 percentile range. These anomalies are highly significant as Swampy was a conceptual target in a poorly explored area. At the Bonita prospect (EL23926) the soil survey showed patchy gold response in the 80 – 100 percentile range over an a rea of 4.5km x 2.5km, open to the west, coincident with a br oad zone of magnetic anomalism. This target was historically very poorly tested, with extensive transported cover, making this a significant result.
Puyurru
Kunkayunti
Chilla Well
Vaughan Springs
Mount Davidson Outstation
Inyalinga
Yaripilangu
Wayililinypa
Newhaven
Haasts Bluff
Kulpitarra UndanditaHomeland
IpoleraHomeland
Kulpitarra
CentralMountWedge
Bunghara
Derwent
Glen Helen
Mt Larrie
Illili
Papunya
Mount Barkly
Milton Park
Narwietooma
Anburla
Tilmouth Crossing
Rubunja Community
Ti Tree
Anningie
Hamilton Downs
Owen Springs
West Waterhole Homeland
Gilbert SpringHomeland
Hermannsburg
Glen HelenTourist Camp
Ljiltera SpringHomeland
McLaren Creek
Jarra Jarra
Old Mount Peake
Numagalong
Wirliyajarrayi
Simpsons Gap
Hamilton DownsYouth Camp
Iwupataka
Aileron
Adeliade Bore
Chianina
Barrow Creek
Alice SpringsAirport
Amoonguna
Ewaninga
Bond Springs
Undoolya
Bushy Park
Yambah
EngenalaCommunity
Stirling
Wilora Communtity
NeutralJucntion
TaraCommunity
Devils Marbles
Wycliffe Well
Singleton
Wauchope
Alcoota
AngulaCommunity
Mount Skinner
Atartinga
The Garden
Todd River
Coniston
Yuendumu
7,400,000 mN
7,350,000 mN
7,750,000 mN
7,700,000 mN
95
0,0
00
mE
1,0
00
,00
0 m
E
1,0
50
,00
0 m
E
7,650,000 mN
7,800,000 mN
7,850,000 mN
70
0,0
00
mE
90
0,0
00
mE
75
0,0
00
mE
80
0,0
00
mE
85
0,0
00
mE
7,600,000 mN
7,550,000 mN
7,450,000 mN
7,500,000 mN
EL29368EL23926
EL29367EL23927
Alice Springs
EL29368EL23926
EL29367EL23927
Alice Springs
Tennant CreekAuthor: J.Rohde
Office: Nedlands
Drawing: J.Rohde
Date: 24/04/2013
Scale: 1:2000000 Projection: MGA Zone 52 (GDA 94)
Figure 1
BONITA PROJECTTenement Location
EL 23926, 23927, 29367and EL 29368
Mount IsaAlice Springs
Tennant Creek
Darwin
Mount IsaAlice Springs
Tennant Creek
Darwin
ABM – GR253/12 Bonita, Group Annual Report 16 March 2012 – 15 March 2013 2
2.0 INTRODUCTION The Bonita project is centred approximately 330 kilometres north-northwest of Alice Springs (Figure 1). The licences area lies in the central Aileron Province – in the north Arunta Region within the Mount Theo and Mount Peake map sheets. Bonita’s south east tenement corner is just 25km away from ABM’s Reynolds Range project tenements and as such the tenements cover a possible northwest strike extension of the Reynolds Range geological setting. On a r egional scale, the Bonita project area is interpreted to have a very complex geology; poly-deformed Palaeo-Proterozoic Lander Rock Formation metasedimentary rocks, known to host gold mineralisation, are intruded by numerous felsic and mafic intrusive phases, and are overlain by slightly younger siliciclastic metasedimentary rocks, including the Reynolds Range Group. The area is covered by complex regolith, with scree shedding from substantial hills cut by large drainage systems. Access to the Bonita project area was via the Tanami Road up to the Yuendumu community and then via the unsealed Coniston track to the Mount Davidson station. From there, station tracks lead to a water bore, located close to the tenement boundary, from where ABM graded a 20 kilometres access track to EL 23926 via Swampy. The tenements have had little exploration and vehicle access further into the tenements was difficult. This report covers exploration carried out in the first year of tenure in period from the 16th March 2012 to 15th March 2013. 3.0 TENURE Exploration Licences 29367, 29368, 23926 and 23927 were granted to ABM Resources NL (ABM) in March and April 2012 for a period of six years. On 20th August 2012 the amalgamated technical reporting for EL’s 29367, 29368, 23926 and 23927 (Bonita) was approved and the group reporting ID GR 253/12 was allocated. The reporting period for this title group was set to 16 March to 15 March with a report submission due date at the 15th May each year. To align the varying reporting period for the four tenements the reporting period for the first Bonita group report was set from each individual tenement grant date respectively to the 15th March 2013. The current tenement area is shown in Figure 1 and Plate 1, with tenement details summarised below in Table 1. Table 1: Tenement Details
Tenement No
Tenement Name
Current Blocks Grant Date Expiry Date
EL 23926 Ngadiri 240 11 April 12 10 April 18
EL 23927 Yinabalbu 244 16 March 12 15 March 18
EL 29367 238 16 March 12 15 March 18
EL 29368 247 11 April 12 10 April 18 In 2011 an Indigenous Land Use Agreement covering EL 29367, 29368, 23926 and 23927 was negotiated by ABM with the Central Land Council on behalf of the traditional owners.
ABM – GR253/12 Bonita, Group Annual Report 16 March 2012 – 15 March 2013 3
4.0 GEOLOGY 4.1 Regional Geology The oldest exposed basement in Central Australia comprises metamorphic and igneous rocks of the Arunta Inlier (Haines et al., 1991). Rocks of the Arunta Inlier are interpreted as being at least partly correlative with sedimentary and volcanic sequences of the adjacent Tennant Creek and Granites -Tanami Inliers. The Arunta Inlier (Early-Middle Proterozoic) is characterised by metamorphosed sedimentary and igneous rocks of low to medium pressure facies. Deformation and regional metamorphism to upper greenschist facies took place between 1810-1750 Ma (Black, 1981). Shaw and Stewart (1975) established three broad stratigraphic subdivisions based on f acies assemblages and l ithological correlations. From oldest to youngest, these subdivisions are named Division 1, 2 and 3. Using this model defined by Shaw and Stewart (1975), the orthogneiss east of Osborne Range, the calc-silicate rocks west of Crawford Range and the Bullion Schist would be included in Division 2, and the Ledan Schist in Division 3 of the Arunta Inlier. Unconformably overlying these rocks are the Hatches Creek Group sediments and volcanics. Blake et al. (1987) formally subdivided the Group into the Ooradidgee, Wauchope and Hanlon Subgroups, comprising a total of 20 Formations and two Members. The Hatches Creek Group is a folded sequence of shallow-water sediments with interbedded volcanic units which reach thicknesses of at least 10,000 metres. The sediments include ridge-forming quartzites, felspathic, lithic and minor conglomeratic arenites and friable arenite, siltstone, shale and carbonate. The Ooradidgee Subgroup consists mainly of fluvial sediments and sub-aerial volcanics which partly interfinger. The Wauchope Subgroup is characterised by large volumes of volcanics and sediments probably both marine and fluvial in origin. The Hanlon Subgroup may be entirely marine and lacks volcanics (Blake et al., 1987). Deformation and regional metamorphism took place between 1810-1750 Ma (Black, 1981). Folding was about NW trending axes while metamorphism to upper greenschist facies took place. Later intrusion of both the Arunta basement and the Hatches Creek Group by granitoids of the Barrow Creek Granitic Complex took place around 1660 Ma (Blake et al., 1987). Contact metamorphism and metasomatism are often observed. Sedimentation associated with the Georgina Basin commenced during the Late Proterozoic with the Amesbury Quartzite and was terminated during the Early Devonian after deposition of the Dulcie Sandstone. The Georgina Basin sequence was mildly affected by the Carboniferous Alice Springs Orogeny. A long erosional period followed with subsequent deep weathering during the Tertiary produced silcrete and ferricrete horizons. A veneer of Quaternary sands and s oils overlays much of the area, except where recent and active alluvial sedimentation is present. 4.2 Mineralisation and Prospect Geology As the interpretation of geophysical data to date suggests similarities to the Reynolds Range geology and style of depositional mechanisms, the mineralisation of the Reynolds Range area is described below.
ABM – GR253/12 Bonita, Group Annual Report 16 March 2012 – 15 March 2013 4
Most of the gold mineralisation in the Reynolds Range area appears to be concentrated along a relatively narrow corridor of greenschist facies Lander Rock Formation meta-turbidites. Where there is good exposure in the central part of the belt at Reynolds Range, folding in the Lander beds has northwest-striking axes, plunge towards the southeast and verges towards the southwest with steep southwestern limbs and gently dipping northeastern limbs (English, 2006). Widespread gold anomalism was identified within greenschist-facies metasediments along the eastern side of the Reynolds Range in the early 1990’s. Gold is hosted by sulphidic quartz veins and has been interpreted to broadly correlate with gold mineralisation in the Tanami region. The Swampy and Bonita prospect areas in the Bonita project are located in the North Arunta region and are comprised of Lander Rock Beds which can be divided into three separate groups; an undifferentiated low grade facies, amphibolite facies including some dolerite and a moderate facies.. It is interpreted that the linear magnetic units are likely to be m ore magnetic BIF or intruded dolerites within the magnetic rock beds (Figure 2 & 3). 5.0 HISTORIC EXPLORATION Exploration over the Bonita target area has been very limited. In 1999 Normandy NFM drilled a 42 km long traverse of 2 km spaced aircore holes (CR1999-0419), of which the five easternmost (Max. Au is 0.004ppm) fall within the south western part of the 2012 EL 23926. In 2000 North Flinders collected 20 laterite samples which fall on the 2012 EL 23926 (and are located at the western boundary of ABM’s 2012 Bonita geochemical survey). Best surface sample gold record was 0.6ppb (Sample ID 5002888) out of a group of the five samples with elevated values. In 2002 North Flinders (Report ID CR2002-0143) completed a total of eleven aircore holes which fall on the 2012 EL 29368. Seven of the aircore holes were drilled on an eight kilometres NS orientated traverse of over ABM’s 2012 Swampy prospect. Best recorded overall historic result was 260ppb gold returned from the line of aircore holes drilled over ABM’s Swampy target area. 6.0 EXPLORATION COMPLETED (from Van Roij) Exploration in the first year of tenure consisted of regional desktop studies, including geophysical and geological interpretations. The review and the magnetic interpretation work suggested that the Bonita area is characterised by similar stratigraphy as the Reynolds Range area and is located along strike of major Reynolds Range. However, due to thicker cover of transported material, and difficult access, the area has historically been left out of systematic exploration and mapping campaigns. Since exploration on ABM’s tenure in North Arunta has historically focussed on gold, no significant amount of electromagnetic surveying (EM) work has been done as it is usually deemed inappropriate for gold exploration. However, other explorers in the region (e.g. Emmerson Resources Limited), have employed airborne EM in 2012 to find weak conductors in areas of very poorly conductive background
Figure 2 Planned Bonita Survey (green) and actual samples taken (black), over geological controls (500k Map sheet Interpreted Geology – North Arunta). Pink - undifferentiated intrusives; Grey/brown –undifferentiated low grade facies Lander Rock Beds (sedimentary marine); Light Blue (stippled) – amphibolite facies Lander Rock Beds, including some dolerite; Dark Blue (stippled) moderate facies Lander Rock Beds.
Figure 3 Surface sampling location Plan at Swampy EL 29368 (Swampy pH SW_GS1 (red) & Swampy regional SW_GS2), over geological controls (500k Map sheet Interpreted Geology – North Arunta). Pink - undifferentiated intrusives; Grey/brown –undifferentiated low grade facies Lander Rock Beds (sedimentary marine); Light Blue (stippled) – amphibolite facies Lander Rock Beds, including some dolerite; Dark Blue (stippled) moderate facies Lander Rock Beds.
ABM – GR253/12 Bonita, Group Annual Report 16 March 2012 – 15 March 2013 5
in the Tennant Creek area. In addition to mapping geological structures with EM, they reported that EM also successfully provided further targets for follow up drilling. The similarities between Tennant Creek and some of ABM’s tenure suggest that EM would also be highly effective to map geology and generate targets in regions which are otherwise difficult to explore with conventional exploration tools (drilling). At Bonita ABM geologists assume that the majority of the mineralisation is narrow and of high grade which is probably set in broad zones of anomalism. A certain structural complexity seems to be the main reason to localize mineralisation in high grade shoots, with first or second order structural features being the source of the mineralising fluid. While no single airborne geophysical technique can be used on its own to generate individual targets (other than massive sulphide deposits), ABM geologists concluded that airborne EM data interpretation will help to identify favourable first or second order thrust or transfer faults as potential sources for mineralising fluids. Historical geochemical sampling data obtained from Newmont and from open file reports were transferred to the ABM database and validated. 6.1 Airborne Geophysical Survey In April 2012 Fugro Airborne Surveys Pty Ltd (Fugro) was contracted to conduct a low level airborne geophysical aeromagnetic survey across three of ABM’s project areas – the Barrow Creek Project (Kroda prospects area), the Swampy (Bonita) Project and the Reynolds Range Project. The airborne electromagnetic (AEM) survey at the Bonita Project was conducted in collaboration with the NTGS, and as such was partially funded by the Northern Territory government under its Geophysical Collaboration Program. Across EL 22396 & 29368 an AEM survey of 58 lines for a total of 1,229 line kilometres, with a 1,000m line spacing and a l ine direction of 42 degrees was completed. T he nominal terrain clearance was 100m. The Fugro’s survey flights over ABM’s tenements commenced on the 21st of June 2012 and covered 1,237km² (Plate 1). The survey flight area was selected to gain a broad overview of the geology and the cover and to possibly correlate it with the geologically better known Reynolds Range area. Furgo processed the data for ABM. Fathom Geophysics Pty Ltd. (Fathom), Perth, did further processing and interpretation work which included conductive plate modelling of the 2012 tempest EM data. The AEM surveyed area included the three kilometre diameter magnetic anomaly known as the Swampy prospect at the intersection of tectonic scale geological structures. In addition to the AEM data, coincidental magnetic data was collected. The flight spacing was half of the open file data available from the NTGS website, however, the flight altitude and speed are not ideal for collection of magnetic data. The resulting data is available in grid format (.ers) of the total magnetic intensity (TMI) and the first vertical derivative (TMI_1VD). Acquired AEM data was made available to ABM in located 3D data (.gdb), and grid format (.ers data of slices in both the X and Z component). Data for each flight line was also collated into a cdi image and exported as images in pdf format. Raw data and cdi images have been submitted to the NTGS on CD.
ABM – GR253/12 Bonita, Group Annual Report 16 March 2012 – 15 March 2013 6
ABM’s interpretation work on the AEM data concluded the following: (from Van Roij) A significant structural contact is apparent from AEM data at the southern end of the Bonita tenements (red dashed line Figure 4). This structural break is not directly obvious from magnetic data (underlying layer in Figure 4), although regional gravity shows similar structures elsewhere on a regional scale. The structure highlighted in the EM data most likely represents a regional thrust fault, which has not previously been identified or mapped, based on similar thrust faults mapped in the vicinity. A similar regional structure was identified by the NTGS in the past and was mapped, approximately 15km south of the Bonita project and extends along the southern margin of ABM’s Reynolds Range project. The public domain gravity data suggests that the new identified by AEM regional fault could continue and form the northern margin of the Reynolds Range project, with mineralised stratigraphy in between these structures. On a tenement scale, the most obvious observation is the thick cover of transported material and deep weathering profile. Elsewhere in the Tanami, cover is generally between 1m to 5m in thickness, with the exception of the occasional palaeo-channel. The average 10m to 40m thickness of the paleo-channel sediments can reach up to 200m. Transported cover at Bonita, north of the thrust fault, appears to be consistently around 30m to 40m in thickness (Figure 5). Figure 4 shows, with green interpreted outlines, the deeper sections of the two parallel palaeochannels, running roughly north – south. South of the regional fault (red dashed line), cover is much shallower, with the two parallel palaeochannels represented by much narrower but deeper channels. From this, it can be concluded that the regional fault moved the southern block upwards. Assuming that the regional fault is indeed a thrust fault, it would suggest a southerly dip of the structure. Alternatively, and s lightly better matching Figure 5, the structure could represent a regional normal fault, with a northerly dip. Higher resolution geophysical data is required to better characterise the regional structure. The Swampy prospect was one of the main reasons for ABMs interest in the Bonita project. The Swampy prospect is characterised by a strong circular magnetic high feature of about three kilometres in diameter (Figure 6) on the edge of a moderate gravity high. The structural setting is also prospective with structures visible from magnetic data to the north and along strike from Reynolds Range. Apart from the interpreted regional fault just south of Swampy (Figure 4, red line) as discussed earlier the the AEM data revealed another regional structure. The area in the direct vicinity around Swampy seems to have the most conductive material at depth. If nothing else, this means that the ground around Swampy has experienced the most extensive weathering, and subsequently a palaeochannel formation (Figure 7). Material more prone to weathering may indicate favourable structures and / or fluid flow, possibly associated with mineralisation. Most gold deposits in the Tanami show a deeper zone of weathering around mineralisation, compared to surrounding unmineralised material. Fathom’s interpretation work concluded that for Bonita project survey, no quantifiable anomalies were recognized in a f irst-pass plate modelling exercise probably due to the thickness of the cover. Transported cover is highly conductive, which makes it difficult to identify conductors at depth. Current will flow in a good conductor longer than it will in a poor conductor, so a flat conductor at surface could have a strong and continuous signal potentially completely masking a conductor at depth. By removing the influence of the overburden from the EM dataset it may reveal more subtle features of stronger conductivity and deeper weathering at the Swampy prospect.
Figure 4 ‘Depth-slice’ image of the 8th band of the Z-component of the 2012 airborne magnetic (AEM) data at the Bonita Project. Background image is the open file (AEM) data. Green lines = paleao-channel borders, red dashed line = regional fault.
Figure 5 Part of a conductivity depth image (CDI) section of one of the flight lines over Bonita. View is to the north-west.
Figure 6 Swampy prospect location on TMI magnetic data (top) and ‘depth-slice’ of band 14 EM data (bottom).
Figure 7 Part of the cdi section of flight line 4602 over the Swampy magnetic target showing interpreted thrust fault.
ABM – GR253/12 Bonita, Group Annual Report 16 March 2012 – 15 March 2013 7
The complete geophysical survey reports and the survey data (GR253_12_2013_GA_01_Appendix1.pdf, GR253_12_2013_GA_04_Appendix4_CD) as well as the report of interpretation of the data are digitally appended (GR253_12_2013_GA_02_Appendix2.pdf, GR253_12_2013_GA_03_Appendix3.pdf). 6.2. Surface Sampling A total of 1239 soil samples were taken on two tenements. All samples were assayed. The samples were originally analyzed for a total of 63 elements but only elements, which showed a response, were included in the final study of the results. In order to create access to the tenement and particular to the geochemical survey areas approximately 40 kilometres of track grading and regrading was completed. The surveys used the Deep Penetrating Geochemistry (DPG) techniques that look specifically for deposits buried under cover with very low (ppb to ppt concentrations) surface geochemical signals. DPG techniques include multiple weak leach techniques, pH & conductivity surveys and very low detection laboratory assays Sampling was generally conducted in accordance to the basic methodology as outlined in the ABM DPG Field Protocols 2012 (GR253_12_2013_GA_05_Appendix5.pdf). The samples were submitted to ALS Perth for sample analysis. The gold ppm - ME-MS23 Ionic Leach method was compared with the results of the gold_ICP21 Fire Assay Result. All sample locations are shown on Plate 2 and 2A. All assay data is included in the digital appendices (GR253_12_2013_GA_09_SurfaceGeochem.txt). 6.2.2 Soil Sampling at Bonita (EL 23926) (from Richards) A total of 467 samples were collected on a 500 x 500 m grid which represents the first part of an extended larger survey designed to cover a wide area, named Bonita prospect, of a conceptual target over a broad trend of regional magnetic features. The Bonita prospect target involves a portion of relatively low amplitude, broad, magnetic feature 15km in width with a NW – SE strike extent of 62km (Figure 8). The magnetic image appears to represent a large scale fold; the core of which has a relatively ‘flat’ magnetic response, whilst the margins of the anomaly image show internal features that likely represent potentially prospective stratigraphy. The limited historic data available for the tenement comprised 19 samples with a maximum gold result of 0.6ppb in conventional soil sampling Geologically the Bonita prospect area is located in the North Arunta region within the Bonita project area and is comprised of Lander Rock Beds divided into 3 separate groups; an undifferentiated low grade facies, amphibolite facies including some dolerite & a moderate facies (Figure 2). It is interpreted that the linear magnetic units are likely to be more magnetic BIF or intruded dolerites within the magnetic rock beds.
Figure 8 Aeromagnetic image over Bonita Survey.
ABM – GR253/12 Bonita, Group Annual Report 16 March 2012 – 15 March 2013 8
The results of the Bonita Geochemical Survey revealed a trend of anomalism down the western margin of the survey (Figure 9). The Fire assay data is inconsistent with the Ionic leach data, and the majority of the data is at or below detection limits (0.001 ppm) (Figure 10). A clustered anomaly in the south-western corner of the survey assayed with the highest Ionic leach gold value for the Bonita at 0.00031 ppm; which is slightly less in comparison with the buried mineralisation confirmed in the 2011 ABM Buccaneer Orientation study. Considering that the transported cover is extensive over this area and there is little outcrop this anomaly is significant. The anomalism at Bonita is spatially coincident with elevated (above background) Ag, As, Sc, and Tl. The Arsenic response is slightly displaced and shows an oc casionally inconsistent signature across mineralisation. Molybdenum occurs at the periphery of the mineralisation response. The complete survey report & results of the test work are appended (GR253_12_2013_GA_06_Appendix6.pdf). 6.2.3 Soil Sampling at Swampy (EL 29368) (from Richards) A total of 772 samples were collected. Two surveys were completed over the Swampy prospect the pH survey (SW_GS1) on two NE SW lines1.45 kilometres apart and the regional survey (SW_GS2) on a 500m x 500m grid. The Swampy geochemical survey SW_GS1 was designed, in conjunction with the regional SW_GS2 (DPG), to target possible mineralisation over a magnetic anomaly (Figure 11). The prospect has limited historical geochemical data (Au only) from a traverse of six AC holes with a 45m to 90m depth across the magnetic anomaly. The max gold assay for Swampy was reported as 0.026ppm (AC hole). Geologically the Swampy surveys are located in the North Arunta region within the Bonita project and is comprised of Lander Rock Beds divided into three separate groups; an u ndifferentiated low grade facies, amphibolite facies including some dolerite & a moderate facies Lander Rock Beds (Figure 3). It is interpreted that the linear magnetic units are likely to be m ore magnetic BIF or intruded dolerites within the magnetic rock beds. The pH geochemical survey over Swampy (SW_GS1) shows a muted response to hypothesised mineralisation. A single point anomaly of 0.00019ppm assayed as the highest Ionic leach gold value for the survey; much lower than the SW_GS2 and the ABM’s 2011 Buccaneer Orientation study results (Figure 12 & Figure 13). Muted multielement and Fire assay results provide evidence that a paleo-channel is greatly affecting the signal of the mineralisation. The elevated gold response is spatially coincident with elevated (above background) Ag, and Mo; although not all samples anomalous in these elements exhibit elevated gold results. The lithological pathfinders are difficult to distinguish and tend not to map spatially separate as they have in other surveys. The pH response over Swampy highlighted potential mineralisation to the NW and SE although the stronger North-west anomaly is not supported by the Ionic leach gold response.
Figure 9 Gold response from the Bonita geochemical survey(EL 23926). The results are thematically mapped in ioGAS using unequal percentiles (0/30/60/80/90/95/98/99/100%).
Figure 10 Contour Image of Au ppm - ME-MS23 Ionic Leach method values (Left) compared to the image of the Au_ICP21 Fire Assay Result (Right).
Figure 12 Schematic map showing the Gold response over the Swampy 1 grid (SW_GS1). The red dashed line shows interpreted trend of the magnetic anomaly. The black lines illustrate the interpreted regional structural trends. The results are gridded in ioGAS using unequal percentiles (0/30/60/80/90/95/98/99/100%).
Figure 13 Gold response from SW_GS1. The results are thematically mapped in ioGAS using unequal percentiles (0/30/60/80/90/95/98/99/100%).
ABM – GR253/12 Bonita, Group Annual Report 16 March 2012 – 15 March 2013 9
The regional geochemical survey over Swampy (SW_GS2) shows a muted response to hypothesised mineralisation. A single point anomaly assayed as the highest Ionic leach gold value for the survey at 0.00035 ppm; comparable to the ABM’s 2011 Buccaneer Orientation study results (Figure 14 and 15). Muted multielement and Fire assay results provide evidence that a paleo-channel is greatly affecting the signal of the mineralisation. This is the lowest Fire Assay results (max Au) for the entire ABM 2012 DPG programme; this may be in part due to the depth of cover interpreted here. 2012 Airborne EM flown by ABM over the Bonita tenement indicates that the depth of cover could be up to 50m. The elevated gold response is spatially coincident with elevated (above background) Ag, As, Cu, Mo and Tl; although not all samples anomalous in these elements exhibit elevated gold results. Both the complete survey reports & results of the test works are appended (GR253_12_2013_GA_07_Appendix7.pdf and GR253_12_2013_GA_08_Appendix8.pdf). 7.0 Recommendations and Conclusions The 2012 AEM data over southern parts of the Bonita project area has resulted in a n umber of observations: - A previously unidentified regional structure was recognized (Figure 4, red line). - Thick cover and deep weathering is present over the majority of the surveyed area (Figure 5 and
7). - Quantifiable anomalies associated with potential massive sulphide mineralisation have not been
identified over the Bonita prospect area. At the Swampy prospect, they may possibly be masked due to the thickness of transported cover and deep weathering.
Future geophysical work should comprise:
• EM data processing which effectively removes the influence of the overburden from the dataset.
• Collection of higher resolution geophysical data over the Swampy prospect and the regional structure to the south of Swampy.
• Amalgamation of 2012 AEM data with public domain magnetic and gravity datasets. • Further follow up of regional geochemical surveys results in context with geophysical
anomalies. From the surface sampling program at Bonita it can be concluded that it is difficult to establish the litho-geochemical signature of the underlying geology when there is little understood about the prospect. A distinct inverse relationship was observed between the sedimentary and igneous pathfinders. Outcrop is scare over the survey area, as is historical data, and transported cover is extensive; providing a difficult terrain for geochemical surface techniques and l ittle solid geological information for interpretation of results. At best the mineralisation can be interpreted as trending on the margins of the interpreted dolerites or BIF. H owever if the magnetic anomalies were BIF the igneous pathfinders theoretically should/would not correlate. F urther investigation needs to be undertaken to define the relevance of this observation to the underlying lithology and mineralisation. These observations and hypotheses will need to be validated and verified in the field and followed up with drilling for absolute confirmation of the litho-geochemical observations. Due to the incomplete nature of the survey and the compelling anomalism on the western margin of the survey it is strongly recommended that in 2013 the remainder of the sampling programme be completed in order to fully investigate the nature of the western anomalism.
Figure 14 Gold response Swampy regional geochemical survey (EL 29368). The results are thematically mapped in ioGAS using unequal percentiles (0/30/60/80/90/95/98/99/100%).
Figure 15 Schematic map showing the Gold response over the Swampy 2 grid (SW_GS2). The red dashed line shows interpreted trend of the magnetic anomaly. The black lines illustrate the interpreted regional structural trends. The results are gridded in ioGAS using unequal percentiles (0/30/60/80/90/95/98/99/100%)
ABM – GR253/12 Bonita, Group Annual Report 16 March 2012 – 15 March 2013 10
The pH survey and the regional survey at Swampy lead to the conclusion that the lithological pathfinders are difficult to distinguish and tend not to map spatially separate as they have in other ABM’s surveys. The standard sedimentary pathfinder’s used by ABM to geochemically define lithologies include Cs, Be, Ce, Hf and Pb; igneous pathfinders commonly comprise Ba, Ca, Ga, Ni and Sr. It is recommended to further investigate the underlying geology before conclusions were to be drawn regarding the effectiveness of the surveying. The nature of the regolith definitely indicates that the mineralisation if present would be incredibly muted by the thick cover over the magnetic target. Further work will need to be undertaken before this prospect can be considered a drill target. Interpretation of the soil survey results, in combination with the geophysical data, suggests that at the Bonita prospect the gold response is consistently elevated on the western margin of the 2012 survey corresponding very well with localised magnetic features (Figure 16). The magnetic data suggests linear magnetic features which likely represent stratigraphy. A fold closure, with complex internal magnetic features, is indicated to the northwest. There is patchy gold response on the northern margin of the survey, but this does not correlate well with the magnetic image features. The overall tenor of gold, in the 60 – 80 percentile range, is slightly lower than ABM’s Buccaneer; however the survey remains open to the west, in an area where the geophysical response indicates a potential fold closure in significant host rocks. At the Swampy prospect, the largest DPG soil survey anomaly generated covers an ar ea of approximately 7km by 2km with a distinct NNW trend (Figure 17). This anomalous area corresponds with several NW–SE-trending, linear magnetic features, which suggests that gold in the area is spatially associated with stratigraphic units, potentially adjacent to a fold closure/hinge zone to the southeast.
Figure 16 Geophysical interpretation at Bonita (EL 23926) over gold response image.
Bonita
5km
Uneven PercentileUp to 100%Up to 99%Up to 98%Up to 95%Up to 90%Up to 80%Up to 60%Up to 30%
Indicative Gravity ContoursRTP TMIHigh
RTP TMITrend
Basement Transform(interpreted)
Figure 17 Geophysical interpretation at Swampy Prospect (EL 29368) over gold response image.
Swampy
Uneven PercentileUp to 100%Up to 99%Up to 98%Up to 95%Up to 90%Up to 80%Up to 60%Up to 30%
5km
Indicative Gravity ContoursRTP TMIHigh
RTP TMITrend
Basement Transform(interpreted)
ABM – GR253/12 Bonita, Group Annual Report 16 March 2012 – 15 March 2013 11
8.0 BIBLIOGRAPHY Black L.P., 1981. Age of the Warramunga Group, Tennant Creek Block, Northern Territory. BMR Journal of Australia Geology and Geophysics, 6, 253-257. Blake, T.U. et al., 1987. Geology of the Proterozoic Davenport Province, Central Australia. Bureau of Mineral Resources, Australia, Bulletin, 226. English, L.T.P., 2006. Reynolds Range Project, Northern Territory, Drilling Completion Report. Tanami Exploration NL internal report. Haines, P.W. et al., 1991. Explanatory Notes 1:250,000 Geological Map Series, Barrow Creek SF 53-6. Department of Mines and Energy. Northern Territory Geological Survey. Darwin. Richards, R., 2012. Bonita BO_GS1, Bonita Regional Project – EL23926, Deep Penetrating Geochemistry (DPG) – Geochemical Sampling Programme, December 2012. ABM internal Report. Richards, R., 2012. Swampy SW_GS1, Bonita Project – EL29368, Deep Penetrating Geochemistry (DPG) – Geochemical Sampling Programme, January 2013. ABM internal Report. Richards, R., 2012. Swampy SW_GS2, Bonita Project – EL29368, Deep Penetrating Geochemistry (DPG) – Geochemical Sampling Programme, January 2013. ABM internal Report. Shaw, R.D. and Stewart, A.J., 1975. Arunta Block, regional geology. In Knight, C. L. (Editor), Economic Geology of Australia and Papua New Guinea: 1 Metals. AusIMM, Melbourne. Van Roij, A., February 2013, Submission to Northern Territory Geological Survey( NTGS), North Arunta Project, Bonita Sub Project, Airborne electromagnetic data acquisition and processing, final report for ABM Resources NL.
180,0
00 m
E
200,0
00 m
E
220,0
00 m
E
140,0
00 m
E
160,0
00 m
E
7,640,000 mN
7,620,000 mN
7,600,000 mN
7,580,000 mN
120,0
00 m
E
EL29368
EL23926
Atlee Creek
Silver Fox
Red Hackle
Tall Ships
Red Blood RAB anomaly
Red Hackle Dam
EL29368
EL23926
EL23927
EL29367
Date: 11/04/2013
Scale: 1:100000 Projection: MGA Zone 53 (GDA 94)
BONITA PROJECTGR253/12
EL 23926, 23927, 29367 and 29368 &Airborne Electro Magnetic Survey