Day 1 in the Field: Learning to Find Ourselves
With a beautiful sunny morning, we headed straight to Victoria Park to look at our first outcrop. The first thing we learned was how to find ourselves. Not necessarily spiritually, but geographically – which seemed just as difficult.
With a beautiful sunny morning, we headed straight to Victoria Park to look at our first outcrop. The first thing we learned was how to find ourselves. Not necessarily spiritually, but geographically – which seemed just as difficult.
After discussing true north and magnetic north, we learned how to use our compasses and orient ourselves with landmarks. We then learned how to discover the events that created the outcrop behind the slide at Victoria Park. Three to four hours later (and quite hungry by then) we had determined the history of the outcrop. Sam Hampton, in his fantastic Kiwi accent, then explained the volcanic history behind our location. We also learned about our new friend GABE (Geologists Always Bring Everything) and used it with the surprise afternoon rain-showers testing out our rain gear.
On our second stop we headed towards the center of the volcano. From our vantage point, we could see the tail of Quail Island and the ridges that had led up to the volcano. Sam explained that there were two volcanoes next to each other and then the unique horizontal lava flow deposits had been left by a third eruption between the two. Lydia also pointed out native New Zealand birds for us!
Our final outcrop of the day was an interesting puzzle that we could not figure out without the help of Lydia, Guil, Liz, and Sam. After learning to look for the different crystal sizes to determine cooling, we were able to figure out which rock was there first and the intrusions. This was a bit trickier as the outcrop had three dikes within another dike.
Day 2 in the Field: Sediment Systems, “the nitty gritty of rocks” -Guil
Day two in the field was just as great as the first day. We first went to the University of Canterbury to have a short lab and group discussion about plate tectonics. We looked at four different types of maps (elevation, volcanic activity, recorded earthquakes, and geochronology) and based on our observations we were able to categorize the three different types of plate boundaries: divergent, convergent, and transform. We finished our lab by asking the question: what type of boundary does New Zealand sit on? New Zealand sits near oceanic-oceanic plate boundaries. To the north and to the south of this boundary, there are two subduction zones that go in opposite directions and they create a transform plate boundary between them. This is why New Zealand is so tectonically active!
We then drove to Taylor’s Mistake (a hiking trail) and walked up to the top of the hill to discuss and see sedimentary systems in action. For some of us it was a wakeup call that we’re out of shape. Others, like Guil and Lydia would have been able to bike up it no problem. Our first stop was at the top of the hill and we had a similar exercise to the first day determining where we were on the map. We then travelled down the hill and went to the shore that was covered with boulders, cobbles, and pebbles. We also looked at a nearby rockfall. The rocks from the rockfall were poorly sorted, angular, and semi spherical. The rocks near the shore, however, were well-rounded, spherical, and well sorted. So what accounts for the difference? The rocks near the shore most likely came from a rockfall, but after underwent erosion and deposition from the ocean (most likely a storm surge or tsunami or similar event).
For our last stop, we went to see a beach and saw the rocks (sand) there. They were well sorted, rounded, and spherical. These rocks were deposited from the ocean. The hike was absolutely beautiful and we were all left in awe of just how beautiful New Zealand is. The weather was perfect. We’re all so excited for what the rest of this trip is going to bring!
On our second stop we headed towards the center of the volcano. From our vantage point, we could see the tail of Quail Island and the ridges that had led up to the volcano. Sam explained that there were two volcanoes next to each other and then the unique horizontal lava flow deposits had been left by a third eruption between the two. Lydia also pointed out native New Zealand birds for us!
Our final outcrop of the day was an interesting puzzle that we could not figure out without the help of Lydia, Guil, Liz, and Sam. After learning to look for the different crystal sizes to determine cooling, we were able to figure out which rock was there first and the intrusions. This was a bit trickier as the outcrop had three dikes within another dike.
Day 2 in the Field: Sediment Systems, “the nitty gritty of rocks” -Guil
Day two in the field was just as great as the first day. We first went to the University of Canterbury to have a short lab and group discussion about plate tectonics. We looked at four different types of maps (elevation, volcanic activity, recorded earthquakes, and geochronology) and based on our observations we were able to categorize the three different types of plate boundaries: divergent, convergent, and transform. We finished our lab by asking the question: what type of boundary does New Zealand sit on? New Zealand sits near oceanic-oceanic plate boundaries. To the north and to the south of this boundary, there are two subduction zones that go in opposite directions and they create a transform plate boundary between them. This is why New Zealand is so tectonically active!
We then drove to Taylor’s Mistake (a hiking trail) and walked up to the top of the hill to discuss and see sedimentary systems in action. For some of us it was a wakeup call that we’re out of shape. Others, like Guil and Lydia would have been able to bike up it no problem. Our first stop was at the top of the hill and we had a similar exercise to the first day determining where we were on the map. We then travelled down the hill and went to the shore that was covered with boulders, cobbles, and pebbles. We also looked at a nearby rockfall. The rocks from the rockfall were poorly sorted, angular, and semi spherical. The rocks near the shore, however, were well-rounded, spherical, and well sorted. So what accounts for the difference? The rocks near the shore most likely came from a rockfall, but after underwent erosion and deposition from the ocean (most likely a storm surge or tsunami or similar event).
For our last stop, we went to see a beach and saw the rocks (sand) there. They were well sorted, rounded, and spherical. These rocks were deposited from the ocean. The hike was absolutely beautiful and we were all left in awe of just how beautiful New Zealand is. The weather was perfect. We’re all so excited for what the rest of this trip is going to bring!
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