Jukes Darwin Area
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3280- '- "1~} J... THE MT. LYELL M. &R. CO. LTD. 1~ICRD'~)L~ED] PRtliM/NARY EXPLORATION' PROPOSALS FOR E.L. 21/76 (JUKES DARWIN AREA) P. BROPHY , I , , JANUARY 1977 , , j I , , , ,, , , I i • I ! I I i I AMG REFERENCE POINTS ADDED 3"2'3]) I J v ~-:G 328002 , I THE MOUNT LYELL MINING AND RAILWAY COMP~ LIMITED PRELIMIN~Y EXPLORATION PROPOSALS FOR EL21!76'(JUKES-DARWIN ~EA) , . 2 '~ I' , , , 1. INTROOUCTION II 2. PREVIOUS WORK Ii Ii 2.1 EXPLORATION. Pre 1965 2.2 EXPLORATION' 1965 - 1972 ii 2.3 EXPLORATION. 1972 - 1976 i , " 3. GENERAL GEOLOGICAL APPRAISAL ; I II 3.1 MAJOR REGIONAL STRUCTURES \, I 3.2 REGIONAL STRUCTURES AND STRATIGRAPHIC ELEMENTS " 3.3 JUKES-D~WIN AREA 11 3.3.1 GENERAL STRATIGRAPHY 3.3.2 MOUNT READ VOLCANICS II 3.3.3 MINERALISATION : ' li 4. PROPOSED EXPLORIITION PROORAMME 11 4.1 AREA 1 KING RIVER-S. JUKES PEAK II 4.1.1 JUKES pry !I 4.1.2 LAKES JUKES I, tl 4.2 AREA 2 S. JUKES PEAK-CONGLOMERATE PEAK fl 4.2.1 INTERCOLONIAL SPUR II II AREA 3 CONGLOMERATE PEAK-MOUNT DARWIN ,I 4.3.1 EAST DARWIN " 4.3.2 FINDONS-ALLANS CREEK . 4.4 AREA 4 MOOt:! DARWIN - 5. DARWIN PEAK 4.4.1 DARWIN PLATEAU fi '4.4.2 PRINCE DJ\.l(ilfIN f 5. BUDGET AliD MAN POiIER 5.1 BUDGET 5.2 MIINPCMER REFERENCES '328003 FIGURES AND MAPS , FIGURE 1 - LOCATION MAP FIGURE 2 - PROPOSED EXPLORATION PROGRAMME AREAS 1 - 5. FIGURE 3 - BUDGET AND MANP(1j/ER AREAS 1 - 5. • ~ - GEOLOGY EL21/76 JUKES-DARWIN AREA MAP 2 - PROPOSED EXPLORATION • - 1 - 328004 PRE~I1-UNARY cu __ ._ REPORT MT. JUKES - MY. DARWIN AREA EL21/76 .. 1. INTROOUCTION: , On ~lst June, 1976, Mt. Lyell Mining and Railway Company Limited marked out en erea of 144 square kilometres covering the Mt. Read Volcanic belt lmmQdietely to the south of ELIO/69 (Dora-Huxley area). Application for an exploration licence was made to the Director of Mines on the 2nd July, 1976, which was subsequently granted on 1st September, 1976, as"EL21/76. I I PREVIOUS WORK: !I 2.1 EXPLORATION: Pre 1965 I i Mining in the Jukes-Darwin area commenced in ,1897 following the initial I discovery of copper mineralisation at Lake Jukes. Further mineralisa " tion was located at East Darwin in 1898, and by 1890 several small prospecting companies were operating in the area. However, most activity had ceased by 1903 following the closure of the Crotty Smelters. II • Various Mt. Lyell personnel worked in the area between 1901 and 1918, II" essentially on adit sampling and detailed investigation of specific II prospects. In 1904, T. Batchelor and W. Cundy both inspected the area II in general and they were followed by W. Morley in 1905-06, L. Williams in " 1908, T. B. More in 1912 and finally R. Murray in 1918. At the same time " a number of Government geologists had also reported on the area including " Twelvetrees (1901) and Loftus-Hills (1914). Little work was carried out between 1918 and the early 1950's apart from II detailed sampling by G. Douglas for Mt. Lyell during 1940. Between 1953 , and 1956, Mt. Lyell recommenced work in the area which included detailed ;1 investigation at the Lake Jukes ?ty and East Darwin workings. However, further work was not recommended due to inadequate access and a greater 'I priority for drilling on the Mt. Lyell Mine Lease. II In August, 1956, the Mt. Lyell Mining and Railway Company Limited with Ii the Electrolytic Zinc Company A/Asia Limited (E.Z.) combined to form Ii Lyell-E.Z. Explorations (L.E.E.) and between 1956 and 1962 undertook I field work in the area as a part of a regional exploration programme in • S.W. Tasmania. A complete reassessment of the Jukes-Darwin area was then undertaken due to the ability of E.Z. to carry out a drilling programme and the availability of a helicopter to transport drilling equipment and personnel. Detailed exploration undertaken by L.E.E. between 1956 and 1962 included: (i) two drill holes in the Lake Jukes mine area,.neither of which intersected significant mineralisaUon (LI-659ft, L7-49lft) (ii) a detailed ground E.M. (turam), magnetic and S.P. survey in the East Darwin area carried out by the Bureau of Mineral Resources (n.M.R.) (iii) a helicupter-borne E.M. survey over Prince Darwin (iv) an airborne magnetic and scintal10meter survey pver the complete Jukes-Darwin area. (v) detailed ground magnetic su=vey at the Jukes ?ty mine • •• AMG REFERENCE POINTS ADDED \ JUKES IJAllWIN MEA £./.. 21/16 • '0 0 ,0 Scm-- - II I777l ..... ..,. ~ - .... 1Aftf' .... -_.-.___ I _.II ~ ---...- ..... -. .... - G:iI .... - ---~-._ ... - II -------.----- •. -- ---at-lolo--·_....-"y----.1_. .- - --1---1-11-_-_.-.- ..... - CJ --.we eri-. .... ---B _. -... ltiJ fJmI - --... M ---. .. __- - E!J _....... I , ........ [A3 - .... ...-._- - ---, - - 3 - ,328006 (vi) a regional mapping programme as a part' of the generalcgeological assessment of S.W. Tasmania. , . I (vii) detailed adit mapping with soil and/or rock chip sampling I at selected locations within the area, but with a specific t emphasis on Findons and Prince Darwin workings ; Results of this exploration programme were not discouraging but full ; potential of the area was not adequately determined due to the need by 1 L.E.E. to divert personnel and equipment to other pa~ts of S.W. Tasmania. United States Metals Refining Co. pegged the area in 1964 (EL2/64) and ! undertook limited field work, confined to mapping, adit sampling and S.P. surveys over the Prince Darwin, Findons and Jukes pty mines. ! Main conclusions from their work were that the chloritic alteration I zones were more extensive than had been originally thought and that a number of west trending faults existed which had not been mapped previously. No further exploration or diamond drilling was carried out in the area by this company. 2.2 EXPLORATION' 1965 - 1972 I 1 The Broken Hill Proprietary Company Limited (B.H.P.) acquired the area ! • as a part of EL13/65 in 1965 which included a large area south of j : Macquaries Harbour. Details of work undertaken on Jukes Darwin are available only since 1969 and, at present, the assumption is made that II B.H.P. concentrated their exploration effort mainly on this southern , portion of the lease from 1965 to 1969. II ~I Initial aim of the exploration programme was to construct an access road to Prince Darwin and test the extent of the mineralisation by II diamond drilling. Later this programme was expanded to include the Intercolonial Spur area where known copper and baryte mineralisation II outcrops at Hydes - Hal Jukes prospects and Taylours prospect respectively. Jukes pty was also examined for possible extensions of the known pyrite chalcopyrite mineralisation. Two holes were drilled from the same drill site south of the Prince Darwin adit. DDHI was drilled west to test an original airborne E.M. anomaly outlined by L.E.E. which was co-incident with a rock chip copper anomaly. DDH2 was drilled east to test a zone of pyrite with a corresponding copper anomaly also from rock chip • sampling. In the Intercolonial Spur area detailed mapping, ground magnetics and rock chip sampling of adits was undertaken in addition to road construc tion and costeaning. A percussion drilling programme was proposed for the Jukes Proprietary mine but was not starteti due to access problems. Instead, a ground magnetic and rock chip sampling programme was carried out in the "area. 2.3 EXPLORATION: -1..972 - 1976 Under a joint venture agreement with S.H.P., International Nickel Australia Limited (I.N.A.L.) took over exploration of the Jukes Darwin area in September, 1972. Initial investigations were carried out by I.N.A.L. to determine the regionll setting and to delineate. areaS of interest. This involved photogeological mapping, surface mapping, geochemical orientation stu~ies and the combined airborne electro magnetic (turair)and magnetic survey over the complete licence. 32800~t - 4 - · , Following these initial investigations seven areas were selected for further detailed exploration. These were. in order or prioritYI FIRST PRIORITY, (i) East Darwin , (li) Jukes Proprietary , SECOOD PRIORITY (i) Intercolonial Spur , , , , (ii) Allan's Creek - Snake Peak , ,• I, (iii) Findon's , , THIRD PRIORITY (1) Eastern slopes of Sumpters Peak (li) Lake Jukes f t Work on the first priority areas included 115.000 scale geological mapping, 111,000 scale detailed mapping of proposal drilling targets, t• and 11500 scale mapping of all accessible adits. Chip sampling of these II adits was carried out over 2 metre sections within mineralised zones and , , , , 5 metre sections in non-mineralised zones. II II Time domain, E.I.P. surveys using pole-dipole arrays were completed in , I both first and second priority areas over a total of 16.5 line kilometres. Results of the detailed exploration indicated that drilling was warranted at East Darwin and Jukes Proprietary but not in the second priority areas. Because of generally discouraging results it was also decided • not to complete any detailed exploration in the third priority areas. , ' II A four hole diamond drilling programme was commenced at the Jukes !i Proprietary and East Darwin during October 1973. Results of this programme are detailed later in the report (Sections 4.1.1, 4.3.1). I However the main conclusions reached by I.N.A.L. as a result of their j drilling werel (i) copper mineralisation did not extend in depth and that surface mineralisation represented secondary enrichment of a leaner primary mineralisation (ii) gold and silver assays were consistently below 5 dwts per ton (iii) zones of mineralisation occur close to the base of a sequence of welded pyroclastic flows laid down on the flanks of the Central Ii Core Lavas.