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surface more or less parallel to the sehistosity planes resulting in smoother and gentler slopes. This feature is well shown in the upper Rees Valley, in the Earnslaw Burn, and to a certain extent on the lake-sides and on Mount Alfred. Apart from the purely physiographic evidence of glaciation, glacial deposits, though not particularly common, have been observed. At the mouth of Buckler Burn, about 2 chains below the footbridge, a hard, well-compacted, dark-coloured glacial till rests directly on solid schist. In this deposit one or two small schist pebbles showing characteristic glacial striae were discovered. Similar glacial till in a small depression about 2,500 ft. above sea-level on the slopes of the Richardson Mountain, a mile north of Temple Creek, also yielded a large schist cobble showing distinct stria;. In the Upper Rees valley a few chains north of Arthur Creek a small creek has exposed a considerable thickness of till that has been deposited on the hillside. Towards the head of the Rees, from Arthur Creek onwards, the valley widens, becomes strongly U-shaped, and has all the features of a glaciated valley. There is a distinct shoulder on its side about 800 ft. to 1,000 ft. above the valley-floor where occurs a notable change in slope which gives a valley-in-valley structure. On the walls of the lower younger valley the streams from the hanging valleys above cascade down in long waterfalls. At the head of the Earnslaw Burn, starting at a point equidistant from Lover's Leap as Arthur Creek, is a similar glacial valley running back [to the cirque of Mount Earnslaw. Here are most marked evidence of glaciation, the schist walls are smoothed and striated, and the valley-floor covered with moranic and out wash material; near the valley head a large recessional moraine practically blocks the valley and rises to a height of 50 ft. above its floor. On the whole the evidence for two periods of glaciation is quite strong, especially as regards the physiographic features of the valley just described. Erom this evidence it appears that the first glaciation carved and smoothed the country to approximately its present topography. The second was in comparison less intense, the ice filling the heads of the main valleys only, oversteepening and deepening them to give the present valley - invalley structure. The large glaciers of the first period, occupying what is now the Rees and Dart valleys, appear to have met at the head of the present Lower Rees valley, where their combined efforts deepened the valley and truncated the ends of the ridges from Mount Earnslaw. The amount by which the combined glaciers deepened the Rees Valley between Mount Alfred and the Richardson Range may have been nearly 1,000 ft. or more, and the ice must have been at least 5,000 ft. thick. This, however, is a conjecture, as the depth to the schist below the present gravel is unknown. Structure. Many minor faults, which generally strike about N. 10° E., can be observed on examination of the small quartz veins, but direct evidence of major faulting is comparatively difficult to obtain. Observations on Mount Judah, Temple Peak, and on the 1,000 ft. wall of the Mount Earnslaw cirque show a series of parallel faults striking N. 20° E. and hading to the east at angles ranging between 40° and 50°. A large zone of crushed and sheared schist is exposed in the Buckler Burn Gorge from the footbridge to Chinaman Flat. This strikes about 15° E. of N. and appears to run towards Chinaman valley and thence across the ridge at the head of Temple Creek, though evidence for this is rather scanty. The whole east flank of Mount Judah, especially the Bonnie Jean Creek basin, has been strongly sheared and crushed, the general appearance suggesting a large intense shear-zone. Crushing and shearing was also observed in the schists in the Jordan Creek Gorge ; whether this is a part of the fault along the Dart valley has yet to be discovered. Schists. Apart from the Pliestocene and Recent gravels, the area is composed of foliated quartz-mica-schist belonging to the Wanaka Series, with the grade of metamorphism. increasing from west to east. Towards the eastern boundary of the subdivision greenish chlorite schists bands of considerable width were observed interbedded in the mica-schists. As a whole the sehistosity planes consistently strike about N. 10° W. and dip to the west at angles ranging from 20° to 75°. Where bedding-planes have been observed they are, except rarely, parallel to the sehistosity. Along the slopes of the Richardson Mountain the sehistosity planes dip west at an average angle of 43°, though there is a tendency for the dip to increase as the summits of the ridges are approached. Along the ridges of Mount Earnslaw the dips of the sehistosity planes flatten to an average of 23°, while the schist outcropping on the eastern flank of Mount Alfred is practically horizontal. The development of quartz veins and reefs is a notable feature of the schists throughout the whole subdivision. In addition to the major scheelite-bearing reefs which strike N. 20° W. and dip to the east at an average angle of 20°, there are numerous small veins up to an inch wide, one set parallel to and the other cutting directly across the sehistosity at high angles. Where the schists have been sheared and crushed these minor veins, especially those cutting across the sehistosity, are strongly developed ; these are common in the lower Buckler Burn Gorge and in the Jordan Gorge. Gravels. One of the most notable features of the topography is the presence of a number of prominent and well-developed, gravel terraces, ranging in steps to a general level 170 ft. above the present level of Lake Wakatipu. Their composition is uniform throughout the district. They consist of wellrounded pebbles and cobble of schist and quartz, and possess no great degree of consolidation.

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