9 -> 
E. DE C. Clakke and C. Teicheht. 
wliose iiitcrofit and local kno^vledg^e greatly expedited our Avork. I't is 
our p]easaut duty to i-eeord liere oiir indebtedness to ^Messrs. Evans and 
Sims, to t\[r. E. Hlood, manager ot‘ t\rure]nson House Station, and to 
Afrs. Blood I'or their li()sj)italily, and to the others on tMurehison House 
Station who were always eager to help us in our work. 
Overlapping vertical aerial photograjdis, covering the entire area of 
our survey were made available to us by the Department of the Army. 
I ntortunately, we did not leai'ii oL‘ their existence until after our return 
from the field, they were, hoAVever, invaluable in the linal preparation 
of tliis report. 
d. Geouuaimjk.'Al _Notes. 
The IMurchison is one of the major rivers of Western Australia and 
is intermittent, as are all rivers in this State between 18° and 30° south 
latitude. It rarely Hoods more tlian once or twice in a year. It rises 
about ->*)0 miles inland ami after traversing tlie Pre-( ’ambrian shield for 
the lirst J/o niile^ oi ils course it enters an area ol sedimeiitai'y rocks 
near Bompas Hill (about 115° 20' east longitude). Here the river b<'nds 
shai'ply and piu'snes a general south-AvesI course. At Rocky I*ool about 
45 miles soiitli-wcst from Bompas Hill it enters ih-e-t'ambriau rocks which 
persist ihi-oiigh Galena to IJardabui Pool, which is about 10 nules south- 
west ot Kocky Pool. Xear Hardabut I'ool the river turns sharplv north 
and h’avej'.ses a seile'^ ot sandstones which is an extension of the Tum- 
blagooda San^lslone described in ibis t>aper. 
Below Ilardabut Pool the river enters a gorge whic-h extends down- 
stnuim almost as far as Mi. Curious where it turns soulh-Avest and floAvs 
to the Indian Pceaii in a fairly Avide valley. On the north-Avost side 
of this parj of tiu* river Hie country rises to a plateau about tiOO feet aliove 
sea-level which breaks oft towards the river in a steep scarp about 200 
feet high lormed ot I ]>per (h’etaceous shales, chalk, and sandstone (text 
figs. Id and 14). I he edge of tlu* -ccarp is broken by broad valleys 
(I Life 1). Tls (op is ])rotecle<l by ‘ Cluricriist, ' ' on the average about 
to feet thick Avhich is somewdiat discoutiiiuously coA^ered by sand, making 
the plat(*aii look like a sand plain, althougli the crust is close to the 
surface and crojjs out in many ])lace<. 
^ Ihe jilateau on the south-east side of this part of the tMurehi-son 
biver is someAAhat loAver (text fig. 7) probably averaging about 450 feet 
above sea-lev(‘I, 1 nt iMeanarra Hill, an erosion Eemnant, rises to about 
5J0 feet (text Mg. .>). The surface of this plateau is i^andy and wo 
did not not:c<‘ any outcrops of durierust such a.s are frequent on the 
higher plafean. There is. however, a latt'vifie layer Irelow the sandy 
surface: this is the lateri/ed top of the Tumbiagooda Sandstone which 
underlies the entire country south of the rhu*r mouth and west of the 
great bend oi the river. Good exposures shoAving the gradual transition 
from fhe sandstones lo (he laterite ean be seen in gravel pits close to 
the point Avhere the road from Murchison Homestead to Ajana reaches 
he general ])lateau level. The laterite is oVerlain bv several feet of 
sand which make very “Imavy going” for motor vebiides. 
The area which we investigated forms part of Ariirchison House 
■ ation. It can hv reached liy motor over a verv sandy track from 
Ajana, the nearest railway station, 35 miles to the south/ Apart from 
