CHAPTEE XIII. 
THE PBEMO-CAEBONIFEROTJS continued. 
THE LOWER BOWEN FORMATION OUTSIDE OE THE TYPE DISTRICT— MACKAY 
DISTRICT. 
The Interbedded basalts, &c., between tlie Middle and Lower Series are not seen along 
the iunction line south of the beads of the Bowen Eiver, so that it appears that a fault, 
which further north throws the basalts, &c., against the metamorphic rooks, to the soutn 
throws the Middle down against the Lower Senes. _ 
The Lower Formation in the coast region, although possessing many M tne 
characteristics of the same series in the district north of the Bowen Eiver Coal I'leW, 
much better developed aud occupies a much larger extent of conntry. Owing o 
intrusion of volcanic rocks no trustworthy estimate of its thickness can be 
making allowance for all contingencies the thickness is probably not less than 1,W0 tee - 
At Mount Do Moleyn on the north bank of the Pioneer EWer, west of Mackay, 
the Lower Series rests upon a coarse volcanic agglomerate resembling that which occurs 
at the head of Pelican Creek. South of the Pioneer Eiver, the Lower Series attains 
groat thickness, and has boon penetrated by granites, dolerites, and basalts, which 
many cases alter the strata in contact with them for a considerable distance, 
heads of the Pioneer a gradual passage from a comparatively unaltered sandstone in o 
granite can be observed ; in no ease, however, has the metamorphism gone so tar as 
entirely mask the clastic character of the rock. , f +lifi 
“ It is a noteworthy circumstance that it is in this, the lovrest member ot 
series that the greatest amount of mctaniorphism has taken place. Indeed no section was 
seen in which it could be confidently asserted that the granitic rocks penetrate th 
higher members of the series.” Mr. Maitland observes that this circumstance may 
indicate that a sufficient time elapsed to allow of the metamorphisin of portions ot tu 
Lower Series before the Middle Series was deposited. 
In the area drained by Eocky Dam Creek, south-west of Mount Eunnel, the 
of the Lower Series have undergone much alteration, some of the grits assuming 
appearance of quartz-fclsites, whilst some sandstones have been altered into quartzi e 
North of Mount Funnel horizontal beds of conglomerate and sandstone, of vario 
degrees of colour and texture, are exposed in several gullies ; near Mount Selwyn o 
bed is a green felspathic conglomerate, in which clear and pellucid blebs of qua 
appear to hare been developed subsequent to its deposition. 
Where the St. Lawrence Eoad crosses Eocky Dam Creek a bed of coarse 
seen, dipping at a low angle to the east. Further up the creek, on its southern an ’ 
in Selection 1142, is a low hill of dolerite, probably intrusive through the sedimenta i 
rocks. In the bed of the creek, higher up, an altered sandstone is seen, and on 
mountain bearing 52° 50' from Mount Funnel, the seaward face consists of a gr 
thickness of an altered conglomerate, penetrated by a dyke of felsite. ^ 
A spur on the western face of Cone Mountain is made up of a massive quar z ^ 
apparently horizontal From this point, in a traverse northward across Eocky » 
and Arrowroot Creeks to the Eildou Hills, altered sandstone and shales are seen 
intervals. 
