Page:Report on the extent of the deep leads of Victoria.djvu/1

 1898.

VICTORIA.

ISSUED BY

JAMES TRAVIS, ACTING SECRETARY FOR MINES, UNDER THE AUTHORITY OF THE HON. HENRY FOSTER, M.P., MINISTER OF MINES.

REPORT ON THE EXTENT OF THE DEEP LEADS OF VICTORIA.

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In reference to Mr. Foster’s expressed desire that the extent and character of the mining resources of Victoria be brought more prominently under notice, I beg to submit the following notes with respect to the great aggregate length of deep alluvial leads as yet unworked, and requiring largo capital for their development, but from all attendant conditions holding out rich promise of success to those who undertake their exploration.

Comparatively few, even among the mining community, grasp the real magnitude of these resources, and I think it would be well to bring the subject prominently under the notice, not only of Victorian, but of British capitalists, as, making due allowance for all uncertainties of mining as regards the amount of gold likely to be won, the existence of these leads is a fact conclusively demonstrated by the boring operations carried out by this Department, while the strong likelihood of their proving payable is warranted by the geological conditions, and in many cases by the actual returns of the pioneer mines now at work on them.

In these notes I mention only what may be regarded as main trunk-lead systems commencing with the westernmost, that of the Ararat gold-field. Here we have all the shallow and worked out leads of the field emptying into a great main lead system covered by basalt from 250 to 300 feet deep trending down the valley of the Hopkins, crossing and then following the concealed continuation southerly of the same auriferous belt of rocks, whence the leads worked northward obtained their gold supply. Two series of borings some miles apart have proved the position of this trunk lead, to explore which several attempts have failed, owing to insufficient appliances and bad choice of sites for shafts. The minimum proved unworked length of this lead is fully 8 miles, and it may extend much further beyond where it debouches from confined limits under the wide plains southward.

The next great system is that extending down from Mount Mitchell northward along the Bet Bet Valley, and thence across to the Avoca Valley. This has been tested exhaustively as regards the existence and position of the lead at three places several miles apart, namely, Caralulup, Lillicur, and Bung Bong, in each of which the existence of a large well-defined lead with heavy wash was conclusively proved. The valley is bounded on either side by Silurian ranges, in which are numerous and extensive alluvial workings. An attempt is now being made to explore this lead at Bung Bong, but so far the whole of its length is absolutely untested as regards payable gold. The length of this system is as follows From Mount Mitchell to Bung Bong 12 miles; from Bung Bong across the Rathscar plain to the Avoca Valley 6 miles (borings have been done on this section by private enterprise, and it also receives the Homebush lead). From where the lead joins the Avoca Valley, near Natte Yallock, down the valley to the plains 24 miles. This section is fed by the extension of the Avoca leads. Total for this system, 42 miles untested.

The next stretch of unworked ground is the up-stream portion of the Mount Greenock lead, between Mount Greenock and Evansford. This has also been proved by borings, but owing to the collapse of the last shaft sunk remains untested, though it crosses a well-known belt of auriferous Silurian rocks, and the depth is only 150 feet.

The down-stream continuation of the lead from Mount Greenock has been much worked, and at its lower extremity, near the junction of the great Loddon Valley system are the worked out Kong Meng and Napier mines at Majorca, and the Chalk’s group of mines near Carisbrook, all now yielding well. The length of the unworked portion above referred to is about 6 miles.