Bulletin - Geological Survey of Western AustraliaGeological Survey of Western Australia, 1903 |
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30th June 50 feet ALFRED WATSON angle auriferous average axial canal band belt Boogardie boundary chains per inch chutes cicatrix considerable Coolgardie copper costæ Crinoid crosscut crushed decomposed dendroidea deposits diabase diorite distance district dollied and specimens drive dykes Edjudina feet in width felsite ferruginous foliated Foord galena Gascoyne River Geol Geological Map GEOLOGICAL SURVEY Gibb Maitland Gold therefrom GOLD YIELD Government Geologist granite greenstone greenstone schists hematite Hexagonella hornblende ironstone Kalgoorlie Lake Raeside laterite lease Lennonville Leonora line of reef lode main shaft miles mineral Mount George Mount Magnet Mulwarrie north and south north-east Northampton Outcrop parallel Perth Plate pyrites quartz reef quartz veins quartzite quartzite bar ridge rock schistose schists showing Sons of Gwalia SPIRIFERA stereom stone stoped strike sunk surface thickness tons Tower Hill Ularring underlie ventral valve vertical shaft W. D. Campbell WESTERN AUSTRALIA
Beliebte Passagen
Seite 2 - Three parallel lines of lode run through this lease in the prevailing north-west and south-east direction. On the most westerly of these a main shaft has been sunk to a vertical depth of 285 feet. Levels have been put in at 275, 200, 100 and 50 feet, and a good deal of stoping done at the two upper levels. This western ore body is some 100 feet in length, and is from two to four feet in width. It consists principally of quartz with varying thicknesses of schistose formation on the walls. At the lower...
Seite 7 - State, and being overlaid only in isolated places by much newer formations : these latter rarely of any great thickness. The Archean rocks he divided into three sections, the granites, the gneisses, and the schists, which, as a rule, run in parallel belts north and south, with a slight trend to the north-west.
Seite 30 - Australia, as a description of an almost identical occurrence has recently been published in the Transactions of the American Institute of Mining Engineers, Vol.
Seite iii - A good deal of work appears to have been done on it in the past, but the shafts have now mostly caved in, :md not very much can be seen.
Seite 8 - Where the reefs have been opened up to water level, many of them contain galena as well as iron pyrites, and the veins seem for the most part, as far as one can judge at present, to be true fissure veins, most of them probably continuing in depth ; but they will vary greatly in...
Seite 5 - GOLDFIELD. The Murchison Goldfield, as originally constituted, was first proclaimed on the 24th of September, 1891; its boundaries were modified on the 15th of February, 1895, so as to embrace an area of about 21,000 square miles. As defined by the authorities, the goldfield is:— Bounded by lines starting from the summit of Mount Murchison, and extending North-Eastward to the summit of Mount Hale; thence EastSouth-Eastward to the summit of Mount...
Seite 58 - The typical lode formations probably owe their origin to a shearing action having crushed and foliated portion of a rock mass in a certain definite direction, producing a more or less well-defined band of rock through which, by virtue of the foliation, mineral-bearing solutions or vapours can have free circulation. In consequence of this, mineral deposits are formed within the rock, usually, but not necessarily, extending over the whole of the foliated zone, but seldom beyond it, and having no definite...
Seite 7 - The fourth or first auriferous belt is situated immediately to the eastward of the granite belt, and is about 20 miles in width. It starts from the south coast at the Phillips River, extending northward in a narrow belt by the Ravensthorpe Range, Parker's Range, Southern Cross, Golden Valley, lit.
Seite 58 - A lode formation may be defined as a more or less vertical zone of rock, usually continuous with the surrounding rock, and of similar origin, but distinct from it in carrying metallic ores disseminated through it in payable quantities, and, as a rule, characterised by strong foliation. Deposits of this nature are probably deep seated ; at Kalgoorlie mining operations have already proved their persistence to 1,500ft.