We woke up after a night spent at the Hotel Skotel Holiday Inn in good spirits. The showers were heated, the breakfast was plentiful, and we were ready for a full day in the field, even after being separated from our home sweet Snowline. Our first stop was along the road on the way to the Mangatepopo Valley Tongariro Crossing Trailhead. We did not know what to expect, but we definitely did not expect to foray through the bushes and newly formed snow from the day before. As we scaled up the mountain, we took a stop at an outcrop, where we whipped out our handy dandy notebooks and went to town on our STC to analyze this mysterious structure.
Through our observations, we were able to determine that the layers in the outcrop were deposited at an angle, facing into the side of the mountain. Although the individual layers were well-sorted, there was a wealth of grain sizes, ranging from very fine sand-sized material to very coarse, cobble-like clasts. We decided that the layers we were seeing were pyroclastic fall deposits. With notebooks in hand, we forged upwards.
We took a stop at another outcrop higher up, and one of the first things we noticed was there were clasts up to one meter across! What could this be, we wondered, confused and cold. Through some delicious hamburger-hotdog-rock analogies, we were able to determine that these large chunks were shot out of the volcano, cooled quickly on the outside, and were deposited before the inside had cooled, allowing the chunk to be flattened and somewhat resemble a very burnt hamburger. We also saw how the layers of the outcrop also faced inwards toward the slope, but at a steeper angle than the last outcrop. Combining our observations from the two outcrops, we came to the conclusion that we were on the edges of a volcanic crater! Bonkers!
We dug our boots in to reach higher up the slope, where we saw a wedge of Oruanui ignimbrite deposited above the crater. What was even crazier was that in the volcanic layers above Oruanui, we found our old friend, Taupo ignimbrite.
Some moments of “What the heck it’s so high up” passed and we went up the rest of the slope and enjoyed a lunch with a clear view of Mount Tongariro, Mount Ruapehu, and Mount Ngauruhoe (Mount Doom from the Lord of the Rings). Descending down back to our van and trusty Sub, we psyched ourselves up for a take 2 of the Tongariro Crossing.
Awesome weather showed us all we dreamed of and tried to infer in our maps of the panorama lavascape between ancient glacier-cut features.
We had determined hearts and snowy boots as we started the first ten kilometers of our hike. We thought we were high before! The mountain met its match as we charged up across 2,000 meters of massive lava flows edged by breccia and etched in our notes—so much easier to write in now that it’s not sleeting! As we neared the crossing, the views kept getting better and better, and snowball fights aside it wasn’t even too cold. The volcanic hazard map near the top was wrong- it said the pre-Taupo Ignimbrite unit was from 1870. Foolish mistake, as we now know!
Our legs getting sore, we pushed on to the moon-like landscape of the Crossing, and even more through the fog to see the view of the other side! I’m not sure what we enjoyed more: the glorious sunset reflected on Ngauruhoe or the burgers (and of course some veggie Risotto) back at the Skotel. Now we just gotta clean up the Snowline lodge and get stoked for the South Island.
Adios!
–Gus and Liam
Through our observations, we were able to determine that the layers in the outcrop were deposited at an angle, facing into the side of the mountain. Although the individual layers were well-sorted, there was a wealth of grain sizes, ranging from very fine sand-sized material to very coarse, cobble-like clasts. We decided that the layers we were seeing were pyroclastic fall deposits. With notebooks in hand, we forged upwards.
We took a stop at another outcrop higher up, and one of the first things we noticed was there were clasts up to one meter across! What could this be, we wondered, confused and cold. Through some delicious hamburger-hotdog-rock analogies, we were able to determine that these large chunks were shot out of the volcano, cooled quickly on the outside, and were deposited before the inside had cooled, allowing the chunk to be flattened and somewhat resemble a very burnt hamburger. We also saw how the layers of the outcrop also faced inwards toward the slope, but at a steeper angle than the last outcrop. Combining our observations from the two outcrops, we came to the conclusion that we were on the edges of a volcanic crater! Bonkers!
We dug our boots in to reach higher up the slope, where we saw a wedge of Oruanui ignimbrite deposited above the crater. What was even crazier was that in the volcanic layers above Oruanui, we found our old friend, Taupo ignimbrite.
Some moments of “What the heck it’s so high up” passed and we went up the rest of the slope and enjoyed a lunch with a clear view of Mount Tongariro, Mount Ruapehu, and Mount Ngauruhoe (Mount Doom from the Lord of the Rings). Descending down back to our van and trusty Sub, we psyched ourselves up for a take 2 of the Tongariro Crossing.
Awesome weather showed us all we dreamed of and tried to infer in our maps of the panorama lavascape between ancient glacier-cut features.
We had determined hearts and snowy boots as we started the first ten kilometers of our hike. We thought we were high before! The mountain met its match as we charged up across 2,000 meters of massive lava flows edged by breccia and etched in our notes—so much easier to write in now that it’s not sleeting! As we neared the crossing, the views kept getting better and better, and snowball fights aside it wasn’t even too cold. The volcanic hazard map near the top was wrong- it said the pre-Taupo Ignimbrite unit was from 1870. Foolish mistake, as we now know!
Our legs getting sore, we pushed on to the moon-like landscape of the Crossing, and even more through the fog to see the view of the other side! I’m not sure what we enjoyed more: the glorious sunset reflected on Ngauruhoe or the burgers (and of course some veggie Risotto) back at the Skotel. Now we just gotta clean up the Snowline lodge and get stoked for the South Island.
Adios!
–Gus and Liam
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