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hills arc large alluvial flats containing deposits of gypsum, potash, and magnesia, 
with salt swamps in places, and here and there hold masses of granite, sometimes 
rising to a considerable elevation, at others only just appearing above the surface. 
The South-Western District. 
The coast between the Moore River and the Lecuwin, including the Darling 
Range. 
The general description of this tract of country is a low sandy plain from 
10 to 20 miles wide, with many swamps and salt-water estuaries, bounded on 
the Eastern side by the bold cliff-like face of the Darling Range. This range 
runs North and South, following the coast, being highest near the Murray River 
and breaking up towards the South coast. 
This coast line comprises a range of cliffs of coralline and shelly limestones, 
and calcareous sandstones, containing Recent shells, and, where the rivers have 
removed these beds, large drifting hills of marine sand occur. These formations 
are mostly overlaid by a white silicious false-bedded sand, often rising into ridges 
50 to 100 feet high, and which inland attain a.n elevation of 300 feet. This sand 
in well sections proves to be a compact red sandstone, destitute of organic 
remains, sometimes attaining a thickness of 40 feet. Beneath this sandstone 
inland are found calcareous sandstones and gritty conglomerates, whilst oyster 
beds and other estuarine deposits are met with in the valleys. 
Immediately underlying these beds, and outcropping in a parallel line between 
them and the Darling Range, are beds of ela.y supposed by Mr. Gregory to be of 
Cretaceous age, and to be an extension to the South of the beds of this age, which 
are exposed at the Moore River, and Gin gin. On the Western edge of this clay, 
chalybeate springs break out. A trial bore made in this formation struck, at a 
depth of 170ft., a stratum of black shale containing fragments of coal or lignite, 
and a great deal of iron pyrites. 
Overlying this clay, and resting against the foot of the hills, are beds of white 
sand, ferruginous conglomerate, and decomposed rock debris, in which have been 
found many pieces of different ores and fragments of garnets and other crystals. 
Flanking the main range (on the Western face) are beds of clay slate, mica 
schist, and flaggy sandstones, with quartz reefs, which, near the Murray, dip 60° 
to 70° to the West and strike 10° East of North, while on the Canning the strike 
is North and South and the dip vertical. To the North these beds change into 
micaceous sandstones, containing quartz veins, numbers of which, together with 
diorite and porphyry dykes occur along this face of the range and are often as¬ 
sociated with metallic ores, though none have been found that were large or rich 
enough to pay for working. The quartz reefs as a rule contain a large quantity 
°} iron pyrites, which on assay has always proved to carry gold, but in no case 
rich enough to work. 
This range, which presents a bold escarpment to the coastal plains, rising to 
au elevation of 1,800 feet above the sea, is principally composed of hard crystalline 
rocks, e.g., granite, syenite, porphyry, and gneiss, containing numerous dykes of 
granite, diorite, and serpentine, quartz veins, and ironstone lodes, covered for the 
most part with cappings of red clay, ferruginous sandstones, grits, conglomerates, 
nodular clay, ironstone, sand, and kaolin, sometimes as much as 40 feet in thick¬ 
ness, and as high as 1,200 feet above sea level. These beds have been classed as 
Devonian, but there are no sufficient data to confirm this view, as they are only 
surface deposits, destitute of stratification and organic remains. 
A marked feature on the South-West coast is the chain of tidal lakes, 
inlets, and swampy alluvial flats which follow the coast, sometimes connected 
witli the sea, and at others separated by the sand-hills. The bars across the 
mouths of most of the rivers keep them fresh for a great, part of the year—after 
