Monday 10 – 4

We have had amazing weather during the entire time we have been here. Our trip from Kaikoura to Hanmer was beautiful. It was great to see the Hope fault in Spring with flowers blooming and the trees a vivid green from their new leaves. We drove into Hanmer Springs in the early afternoon. As we crossed the bridge above the Waiau River we saw a man strapped to a bungy cord preparing to jump off the bridge into the gorge below. Not wanting to pass up a good spectacle we pulled across the bridge and watched him go. He came pretty close to hitting the water. I tried to get Paul to try it but he wanted no part of it. We then went to view some trench sites where Rob Langridge, Will Ries and I trenched during our investigation there in 2008. The Hanmer Basin is a large pull-apart valley formed by a right-step of a few kilometers in the dextral slip Hope fault. The northern part of the valley consists of a series of large normal faults upon which the town of Hanmer Springs is built. The faults are active. We have been trying to determine just how active they are and how they relate to the activity of the Hope fault. Hot springs that flow from the faults have been developed into health spas making the town a destination spot. 

After spending a couple of hours in Hanmer we headed to Lewis Pass. The road to the pass is amazingly beautiful. Enormous flights of river terraces flank the Waiau and Hope Rivers. In at least one place the Hope fault deforms all but the youngest terraces. We got to Lewis Pass in the late afternoon. This is an exceptional location as the Alpine fault runs through the pass and through a large flight of river terraces. The area has been studied for years and is a favored field trip location for Kiwi geology classes. At this northern location the Alpine fault is starting to dump its strain onto faults of the Marlborough fault system, such as the Hope, Clarence, Awatere and Wairau faults. Thus, individual slip events are somewhat smaller than the 8 to 10 m of horizontal slip that are typical of the central part of the fault. In addition, during each event, there is a small amount (less than 1 m) of vertical slip on the fault. The river terraces exhibit a long history of faulting with older, higher terraces offset greater amounts than the younger, lower ones. We put on our gum boots (rubber boots) and walked through the wet field to see the fault. In the middle of the field a low, long, dark gray wall extends across the fault. The wall was constructed across the fault in the 1970’s in an attempt to document whether the fault creeps. Today, the wall is as straight as the day it was constructed. A sign erected next to the wall proclaims that this is proof that the fault doesn’t move slowly. This proclamation has been a source of debate among geologists. The question exists, did they build the wall long enough to capture the between earthquake deformation of the fault? Is the wall rotating within the fault zone as a rigid beam? New maps have been created recently of the terraced field. Perhaps the story will soon become more clear.

We spent the night in Reefton, a coal and gold mining town on the west coast. We camped in a field, that, turned out, in the morning to be the town rugby pitch. From there we headed down the coast through Greymouth and on south to Franz Joseph. We drove along the eastern Tasman Sea for a few hours. The South Island West Coast is famous for its heavy rains and hard winds. This day was beautiful, sunny and warm. Deep forests and fern bush line the roads except for paddocks that have been cleared for sheep and dairy. The spectacularly steep and white South Alps dominate the view to the east. A few hours later we were in Franz Joseph, the site of the Franz Joseph glacier. During the end of the last glacial maximum the glacier actually extended kilometers west of the current coastline. Now it is retreating rapidly as it has been doing for at least the last 200 years. We took a walk up to a lookout where we could view the glacier coursing through deep native rainforest. It is quite a sight.
We then drove back up the coast and turned inland to go to Jackson’s on the west side of the Alps along the Alpine fault. This is another location that Rob Langridge, Will Ries and I trenched in 2008. The area is surrounded by incredibly steep mountains with huge alluvial fans and debris chutes. It was nearly dark. The mountain “tops” were bright orange. We set up tents at one of the few inhabited places in the area. That night, the sky was amazingly bright from the Milky Way, Mars and Jupiter in the sky. The Magellenic clouds were enormous. 

We awoke to the “whump-whump” sounds of Wekas (chicken-sized flightless birds) and their chicks exploring around our tents. Bell birds and Tuis were singing loudly; what an amazing alarm clock. The morning was grey and damp. We attempted to dry our tents so they could make the flight home. A short drive to the west brought us to the beautiful Arthur’s Pass. This is the area where the troupe in Lord of the Rings made it through the high peaks. At the top of the pass we stopped to view the Keas (pronounced Kee-Ahs). They are large alpine parrots. These are amazingly beautiful and mischievous birds that show no fear of people. They fly right up to you and pose for photos. If you are not careful they will also fly to your car and pull your windshield wipers and antenna off the car. 

We are now sitting in Christchurch airport about to board the first leg of a long flight home. We’ll take our first flight to Auckland where we’ll catch a 12 hour flight to San Francisco and then Arcata. Our flight from here leaves on Monday at 4:30 pm. If all goes as scheduled we will arrive home at 4:56 pm on Monday. So, we should only travel for 26 minutes. You have to love the International Dateline.

Now will be days of catching up on things that have been ignored for the past 10 days. We have learned an incredible amount from this earthquake. I think this has proven to be a great learning experience for Paul. We’ve made great contacts with fellow researchers from GNS Science, Canterbury University and Penn State. Thank you again to all who have made this trip possible.