Editorial October 2010
The UK has absolutely splendid geology, we are all agreed, but apart from geomorphological processes and sedimentation in our seas and water bodies, the greater glories of actuo-geology (if I may be permitted to invent a new word) are largely denied to us. By actuo-geology I mean glaciers, plate boundary phenomena (i.e. volcanoes, earthquakes, thermally active areas), etc, actually doing their thing before our very eyes, now, as we witness it. The most recent UK volcanism, for example, took place 50-60 million years ago. However, the world being a wonderful place, if one is prepared to travel, almost any geological process can be seen happening right now. And nowhere, in my opinion, beats New Zealand for sheer breadth of experiences available to the geo-tourist. What this is leading up to of course, is an excuse for me to tell you about our holiday to NZ for the month of September. Joanne was to deliver a talk at a conference in Auckland, so we decided that if we were travelling all that way, we might as well stay for a month, hire a car and see as much as we could. We knew generally what to expect from background reading, but nothing prepared us for the sheer spectacle and thrill of standing in front of the Franz Josef Glacier (or the Fox Glacier for that matter) and getting an on-the-spot tutorial of exactly how glaciation works. To see U-shaped valleys in the course of formation, moraines being dumped, hanging valleys being created, outwash gravels and sands being deposited at my feet, was an awe-inspiring experience for any red-blooded geologist. Just the scale of it all is overwhelming, but then it is realised that this is only one little glacier in a shrinking field. I tried extrapolating it in mind’s eye to a glacial landscape from horizon to horizon, and got just the merest glimpse of what the Pleistocene and other periods of global ice really meant.
From that cold world it was possible only a day or so later to experience quite the opposite, where it is heat and magma that drive the landscape. As everyone knows, a major plate boundary runs along the western side of the South Island and then dodges somewhat to the east of the North Island, and the interraction between the two plates is responsible for the creation of the Southern Alps and all the earthquake and volcanic activity. The volcanoes are largely quiescent these days, and significant eruption has almost ceased, but there is lots of other activity, particularly around Lake Taupo (itself a magnificent example of a crater lake on a vast scale) and Rotorua. You ain’t heard nothin’ until you’ve listened to the contented plooping and plopping of a bubbling mud pool. And to watch a geyser suddenly going off before your eyes, or see the wonderful multicoloured terraces created by mineral-rich steaming streams and springs, is a special experience.
But living near a plate boundary can have serious drawbacks, and we received a salutory lesson in just how vulnerable NZ is when we heard about the Christchurch earthquake as we woke on our second day in Auckland. The whole country was buzzing and wondering what it could do to help. 7.1 is quite an earthquake, but incredibly no-one was killed. It wasn’t expected, at least not along the faultline whose movement was responsible, but aid was rapidly mobilised and the dedication of the aid-teams was remarkable. We arrived in Christchurch a week after the ‘quake hit, expecting devastation everywhere, but the place appeared almost normal. That was deceptive, as much of the damage was not immediately obvious, being in the form of insidious but structurally significant cracking in superstructure, drains, sewers, etc. That’s not to say there weren’t any collapsed buildings, there were, but the pattern tended to be that vulnerable and old buildings were picked out for destruction, while all around, the majority remained standing.
As if the glaciers and plate tectonic landscapes weren’t enough, there is seemingly an endless supply of other ‘wow’ scenery and geology, far too much to go into here. The west coast fjords for example and the wild almost deserted coast further north, or the untouched primeval forest that covers large areas, particularly in the wonderful South Island. Only 4.1 million people live in NZ, and 1.4 million of them in Auckland, so it is very easy to imagine you are the first person to set foot in some of these special landscapes. My favourite? Well, none of the obvious choices, but a very remote, bewildering and beguiling area known as the Rangipo Desert, north of Waiouru and south of Taupo. I’d never seen anywhere like it, it is crossed by only one road, State Highway 1, which is known there as the ‘Desert Road’. The area consists of hundreds of square kilometres of plateau created by the activities of neighbouring volcanoes, completely empty and wild with a spectral beauty. Not a tree, just low scrub and barren volcanic soils for as far as the eye could see.
Turning briefly to other matters, the Section broke new ground, at least in our recent history, by having a field excursion in October. That wasn’t as intended, but bad weather earlier in the summer meant that our trip to the Ancaster area had to be re-scheduled for October 9th. A report on the day will appear in the next Charnia, also one for the Bradley Fen trip in September.