ARTESIAN WATER IN N. S. WALES AND QUEENSLAND. 495 
to above in the northern half of the Cretaceous basin ; but beyond 
the fact that the elevation was subsequent to the deposition of the 
Upper Cretaceous rocks, the Desert Sandstone, little is known as 
to the date of the upheaval. The radiolarian earths elevated toa 
moderate height above the sea, described by Mr. J. G. Hinde* 
are thought to be of probable Tertiary Age, but it is stated that 
these earths are the equivalents of the so called “‘ magnesites,” 
described by the late J. E. Tenison-Woods. These magnesites 
are now several hundred feet in places above sea-level to the south 
of Port Darwin, and if the above suggested identity can be proved, 
portions of the northern coast of Australia must have been elevated 
by a similar amount since some portion of the Tertiary Era. 
It is at any rate certain that whereas the top of the Marine 
Cretaceous strata are not more than about 700 feet above sea-level 
at the south-east extremity of the Cretaceous basin near Narromine 
in New South Wales, the same horizon is over 1,300 feet above 
sea-level in the latitude of Roma, 1,200 feet in the latitude of 
Hughenden, and 1,020 feet above sea-level at the top of the Divide, 
between the Flinders and Thomson Rivers. The Marine Cretaceous 
rocks therefore are about five or six hundred feet higher to the 
north of Roma, at Darby Point, and to the east of Hughenden 
than in New South Wales. It would seem then, that since the 
close of the Cretaceous Period, the northern end of the basin was 
first uplifted 1,300 to 1,400 feet, then the south-west extremity 
since Miocene or early Pliocene Time underwent a total elevation 
of six to eight hundred feet, and possibly the north-east extremity 
of the basin has shared with Cape York and the Great Barrier 
Reef in a downward movement during perhaps late Tertiary and 
Post-Tertiary Time. 
Some have found a difficulty in the way of accepting the opinion 
that the water in the artesian basin is in circulation through sub- 
marine outlets because of the smallness of the fall in the surface 
between the level of the intake and the level of the overflowing 
wells. For example, the surface level at the Muckadilla Bore is 
* Quart. Journ. Geol. Soc., London 1893, Vol. x1LIx., pp. 221 - 26. 
