110 



E. 0. Teale 



Mount Tara Goldfield. — It is in the northern half of this Ordo- 

 vician area, extending over a distance of about four miles, that 

 ithe now abandoned Tara goldfield is situated (24 and 25). Nume- 

 rous old prospecting shafts and open trenches occur at intervals 

 throughout the field, but most work has been done at the northern 

 end, in the vicinity of Lady Ibrr Creek, where there are a number 

 'Of adits and shafts. 



All the accessible adits Avere examined, and roughly sectioned.' 

 These observations, together with those above ground, show clearly 

 ihat the rocks are very much disturbed, faulted and sheared. The 

 line of crushing and\ shearing lies between N. and S. and N.N.E., 

 .and coincides roughly with that oif the old mines. Though some 

 quartz occurs, it does not appear to be in the form of a defined 

 quartz reef, and the lode formation seems to be of the type of a 

 fracture zone of crushed rock with some quartz and gossany mate- 

 rial. 



The strike of the rocks is generally N. to N.E., but at the north- 

 «rn end of the field there is much variation, no»rth -westerly and 

 ■even, westerly strikes being observed close to the normal direction. 

 This is well shown in some of the adits, where numerous faults with 

 a generally northerly trend are revealed. Most mining appears 

 to have been done at the ** Orbost Tunnel " (Au. No. 9 on Map 4), 

 where there are two adits and some stoping has been done along a 

 fault line, striking 10 degrees east of north and dipping W.N.W. 

 at about 65 degrees. 



The auriferous occurrences are in general confined to the Ordo- 

 Tician belt, but gold has also been obtained in the porphyry, about 

 half a mile to the north of the termination of the Ordovician. Ihis 

 was at the '* Tara Crown," (Au. No. 2 on Map 4), Avhere it was 

 associated with galena. This is probably a continuation of the 

 fracture zone, which intersects the Ordovician. 



«l) ORDOVICIAN 



J\i fern a tin a thin beJs of 

 sandstone and shate. 



.LOWER DEVONIAN 



Asfi heds J wellhedded w'ifh dffernatinn coarse and fine Ms 

 cff dticf strike s/'m/f^r fo 

 ^i/f i/nconfnrmabfe. 



i 



SECTION c. Boggy Creek 



Scale r i" 



y«'^« 



