geology field trip
August 14, '04

(click on the first picture to get started; captions are at the bottom of each picture page)

On this cloudy Saturday I had a Geology field trip around the mainland side of the Otago Harbour. Here is one of those classic reflection-in-the-water photos. Some of the class checking out this large outcrop of weathered, volcanic rock.
We then drove out to "Spit Beach" at the end of Otago Harbour. Looks like it'd be a nice place in the summer... today it was quite windy and cold. We climbed up the rocky formation at the edge of the beach to check out some more rocks.
I don't actually know any of these people, but there you go. The silly thing about this field trip was that we spent a lot of time staring at rocks, having absolutely no clue what we were staring at - but the prof wanted us to *try* to figure out what the rocks were. So after staring at the thing for 5 minutes he would say so yeah, it's clearly a phonowhosawhatsite. We'd shrug, sure... never heard that word in my life.... Looking the other direction up the coast of New Zealand
An outcrop we visited higher up the slope. The professor is the guy at the far end musing at the lovely rocks. They may just look like rocks to you, but actually it is amphibole basalt with unusual phenocrysts and xenoliths separated by fine-grained tuff. Yes, this is how they "explain" stuff! As far as I can tell, all that it means is, the rock used to be hot and liquid, and contains bits of other types of rocks and crystals. In this case, a particular mixture of bits of rocks and crystals that is not found anywhere else in the world. While listening to another scintillating round of geological gibberish, I decided to embark on a photographic feat. You've seen horizontal panoramas, and maybe vertical panoramas, but today, my friend, I combine 6 pictures to bring you... a Triangular Panorama. Seeing is believing.
This is pretty nice - a cross-section of magma that was pushed up through the orange rock to form a dike (the vertical part) turning into a sill (the horizontal part). Another awesome artsy shot.
Seems like there are container cranes everywhere in the world. These are at Port Chalmers, a town halfway out along Otago harbour. A railroad tunnel in Port Chalmers.
Finally, the view from above Port Chalmers out across to Otago Peninsula. The upshot from our field trip was that the lumpy islands in the middle used to be the center of a large volcano. 10 million years of erosion and sea level change turned it into this harbour.