24 
The N.Z. Journal of Science and Technology. 
[Mar. 
clays, and claystones that became more compact in depth. These are 
evidently part of the younger Tertiary beds well exposed on the right bank 
of the Waitahu a mile down-stream from the coal-mine. If the coal- 
measures maintain an average dip of 1 in 4 the first coal-horizon should 
be reached in this bore at a depth of about 1,800 ft. 
The gravels of the structural valley are probably underlain by coal- 
measures to as far north as Burk Creek, a branch of Boatman Creek, and 
as far south, as Devil Creek. And these may not be the limits of the con¬ 
cealed coalfield. The structure of the coal-measures below the gravels, and 
the number, thickness, and distribution of the seams therein, will best be 
ascertained by boring. It is probable that the amount of coal below water- 
level is many times more than that occurring above it. 
Notes to accompany a Geological Map of the Cheviot 
District. 
By J. Henderson, D.Sc., Mining Geologist, N.Z. Geological Survey. 
The following notes on the geology of the Cheviot district are in con¬ 
tinuation to those already published,* and the accompanying sketch-map 
is from data collected during the writer’s brief visits in May, 1917, and 
November, 1919. 
Physiography and Structure. 
The area mapped, in all about 90 square miles, lies between the lower 
courses of the Waiau-uha and Hurunui Rivers, in the south-east corner of 
the old Provincial District of Nelson. It consists of a depression extending 
northward from the Hurunui to beyond the Waiau-uha. On the west it 
is bounded by the Benmore Hills, beyond which rise the Lowry Peaks. 
On the east the Cheviot Hills separate the depression from the sea. 
A fault-zone bounds the depression on the east, a similar zone probably 
occurs on the west, and the lowlands thus consist of an elongated strip 
let down between relatively elevated blocks. At the southern end of the 
Cheviot Hills is another but smaller trough between faults that strike east- 
north-east. Several faults cross the southern portion of the Cheviot Hills, 
where they appear as wide crush-zones striking west-north-west. These 
were not traced across the depression, but McKay in his report of 1902 
describes the most severe effects of the earthquakes of November, 1901, 
as occurring in the lowlands along the extension of the two crush-zones 
shown in the map crossing the southern end of the coastal hills. 
The lowlands consist of gravels and soft Tertiary and perhaps Cretaceous 
beds, whereas the uplands are carved from older and much more resistant 
rocks. The northern half of the depression drains to the Waiau-uha, a 
* Notes on the Geology of the Cheviot District, N.Z. Jour. Sci. & Teclu, vol. 1, 
pp. 171-74, 1918. To the list of literature given in this paper add : R. Speight and 
L. J. Wild, The Stratigraphical Relationship of the Weka Pass Stone and the Amuri 
Limestone, Trans. N.Z. Inst., vol. 50, pp. 79, 80, 1918 : and R. Speight, Structural 
and Glacial Features of the Hurunui Valley, ibid., pp. 93-105. 
