Otago Provincial Gazette – 1863 – No. 259

Page 302

✨ Mining Report

302

Shotover, as the main gullies—viz., Moak, Stoney, and Skipper’s Creeks—contain in their beds immense boulders of quartz; and so also does the Shotover at their junctions—the stone in many places being highly auriferous.

Terraces.—These (of which I have made mention in a former part of my report) form the most peculiar feature of the district: they may be seen to some extent in every place where the action of running water can be traced; throughout the courses of rivers, on the borders of the lakes, and upon all the alluvial flats these geological phenomena present themselves.

The terraces at Arthur’s Point are a gradation of alluvial flats, the one above another.

Sketch Section of Terraces near Maori Point

Alluvial Flat.

RED ROCK OF MICA SCHIST.

Their level on the top, and each having a slope of about two to one: they much resemble in appearance and regularity of form, the embankments of railways, or other similar earthwork. The soil at the surface is generally of a rich loamy nature, and carries abundant vegetation. One of the most extensive of these terraced flats lies between Maori Point and Skipper’s, on the western side of the Shotover. By examining the steep river banks at both these places, together with the four creeks that intersect the terraces on their way to the Shotover, it is plainly seen that the ancient river beds of Skipper’s have flowed beneath the existing drift deposits. I give a sketch section along the southern bank of one of these tributaries in which all three gutters as well as the terraced surfaces must at different times have been river beds, and there is, as near as I can judge, some six hundred feet between the two levels. It is plainly to be seen that the junction of Skipper’s and the Shotover was originally at Maori Point, and that these three gutters were at different times ancient watercourses of Skippers, but to account for such heavy drift deposits is difficult. There exists at Maori Point, or a little south of it, evidences of heavy land slips having taken place, the debris of which appears to have been thrown across the river bed; this, by forming a natural dam, has headed up the water and converted the valley behind it into a lake, and there being no means by which the subsequent drift deposits could escape, they settled, and accumulating, formed a false river bed, which, by the water forming fresh channels, became from time to time.

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