Page:Quarterly Journal of the Geological Society of London, vol. 28.djvu/348

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of this bed is in both places about north 30° west, which line would connect the two outcrops, although nearly 300 miles apart.

In the limestone bands which form the lower portion of the series (shown in Fig. 12), corals are very numerous ; in fact the limestones,

Fig. 12. — Section of Devonian Coral Limestone, Terrible Creek, near Messrs. Cunningham's Cattle Station, Burdekin River, Northern Queensland.

where little alteration has taken place, are a mass of aggregated corals ; and as this class of rock has resisted aerial destruction better than the associated slates and sandstones, the barriers thus formed mark the trend of the rock- system to which they belong, in a very picturesque and decided manner ; their bold, massive and varied outline chiselled into the most delicate fretwork by nature's hand, is relieved by a wealth of richly tinted foliage, unknown in the surrounding bush ; and the eye jaded with the monotony of the " eternal Gum-tree " turns with delight to the changing tints and varied scenery presented by these barrier-like records of the past (Fig. 13).

On the Broken River, a tributary of the Clarke, in Northern Queensland, the entire Devonian system, as developed in Queensland, could be easily and satisfactorily mapped. The branches of this river cut right across the strike, and the bare edges of the rocks are often exposed over the intervening ridges from creek to creek. Well- marked beds of interstratified conglomerates seem to retain their character over large areas ; and the loose pebbles from these can be followed readily over the ridges, whilst the rocks from which these pebbles are derived crop out in the gullies and ravines.

As a large proportion of them are of quartz, the ridges covered by them are often mistaken by miners for indications of a "deep lead"