GETTING STARTED IN OTAGO GEOLOGY

Going for a degree in Geology? The University of Otago is a fantastic place to do this, not least because it's in the middle of an extinct volcano. Once upon a time, a basaltic mound 1000 m high stood where Dunedin now is. Ten million years later we have students marveling at the remnants of it. There are hints of ancient lava flows, ash falls and massive eruptions. All just in one city!

To get started with your Otago Geology degree, you'll need to take the paper known as EAOS111. That's Earth and Ocean Science for first-year students. As well as geology, this paper covers aspects of marine and environmental science, with a lot of material to learn. Or as I think of it, something for everyone! There's even a whole lecture devoted to dinosaurs.

In EAOS there are four lectures per week, as well as a three-hour lab session. (To be honest, most of the labs can be finished in two hours.) Content of the labs is quite varied; one week you'll be sketching fossilized critters, another week creating a model ocean, another again learning how to locate the epicentre of an earthquake. The lecturers are a talented bunch from several departments and they include Professor Ewan Fordyce, who last year was awarded the Hutton Medal for earth sciences.

Also there are a number of field trips, that number being four. Two of them are entirely focused on the geology of the Otago region. First you'll be taken northward to explore a few sites between Dunedin and Oamaru, a city famous for its building-quality limestone. In nearby Boatman's Harbour are some excellent examples of 'pillow lavas' which formed in an undersea eruption. Each dark blob in the photo below is a single 'pillow' and some of them grew to great sizes before they cooled and solidified millions of years ago.

 

Pillow lavas at Boatman's Harbour, friend gives scale. Photo courtesy of Tom Stevenson.

If those 'pillows' formed under water, why are they now above the sea? That's because the land around has since been uplifted along faults in the rock. Such processes happen over unimaginably long periods of time, which you get a feel for on the Taieri field trip. For those readers who live outside Dunedin, the Taieri plain is located just to the south-west and is crossed by the Taieri river, which drains into the Pacific Ocean. Around here are features of a quite different nature, sediment and sedimentary rock built by the river itself.

Over time this river cut through the schist bedrock located to the west, ground it up and deposited it in sediment. Some of this sediment is now breccia, a type of rock made up of angular fragments. The Henley Breccia formation is found on the eastern side of the Taieri plain and was formed around the time of the last dinosaurs. Perhaps there was once a dinosaurian ecosystem around this river; will we ever know for sure?

Another trip takes you to Portobello, specifically to the marine lab where living specimens of all kinds of creatures can be studied. Here you'll learn about how the living world is organized and how we classify living things. Here's a starfish, a spiny-skinned echinoderm that can launch its stomach out of its mouth. There's a bryozoan, or lace coral, a colonial filter-feeder.

Finally there's the trip aboard Polaris II, the university's famous research vessel. Originally a tuna fishing boat, it's been converted for scientific purposes. Students on the vessel will learn how sound waves can be used to map the seafloor, how the composition of water changes as you leave the Otago Harbour, and hopefully how to not be seasick. You'll go right to the end of the Otago peninsula and see fantastic basalt cliffs, also remains of that old volcano. Soaring albatross and basking sea lions add that warm, fuzzy touch that makes a great day outdoors.

If you're in your last years of high school, looking for a new degree, or just curious about geology study, this is where you shall start. EAOS111 is taught in the first semester every year at Otago.