At long last some fieldwork of my own. My field area encompasses some of the most remote, trackless portions of New Zealand, including several large rivers that are uncrossable following rain, thick bush and ample sandflies. I spent a week with a field assistant camping near the Jackson River Road (only region of field area less than a day's journey from a road) and making day trips into the creeks and rivers in the area desperately looking for outcrop. Success was moderate. Weather was lovely and the fast-flowing rivers were mostly negotiable with a bit of care. A few crossings reached the critical level above my waist where I start floating downstream- one of the many uses of field assistants is not letting this happen. The water was cold, the valleys were rough, and the outcrop challenging. It is clear I will need a raft to get to some outcrops and set up some ropes to rappel down to others. A previously-described key outcrop is wholly non-existent, succumbed to landslides and bush in less than 5 years. Another important outcrop (above) has much better exposure than last-described. It is amazing how dynamic these river valleys are- they literally change from year to year. I was confined to my car for an entire day as continual rain flooded the rivers and creeks and rendered all uncrossable. Sandflies were voracious and a reason to hide in the car even when the weather was fine. Field work logistics seem to be getting complicated and this is by far the most accessible region of my field area. Others will necessitate helicopters, and possibly jet boats and whitewater rafts. In short, it was largely a reconnaissance trip with lots of slippery rock negotiating, bush bashing, river crossing and occasional geologizing. At least I know what I am in for...
Before heading back to Dunedin, I crashed an international geology conference on the Alpine Fault. A quick sidetrip was taken to look at rocks in the Hokitika Gorge. Nearby I got to see several trenches dug through Alpine Fault traces to determine paleoseismic events. One earthquake appears to have caused 1.5m of vertical offset and about 8m of horizontal motion over a length of several hundred kilometers!
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| Hokitika Gorge |
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| Alpine Fault paleoseismic trench |
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| In the trenches |
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| A West Coast beach |
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