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Roaring Girl
The adventures of the yacht Roaring Girl wandering the seas.
Above Cathedral Cove
29/02/2008, Hahei


Places and people
Working in Wentworth Valley
28/02/2008, Wentworth Valley DOC


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Moving the pump-house


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That's a big hole
28/02/2008, Waihi


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Waka in Tauranga
27/02/2008, Tauranga Bay


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Back to harbour


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A barren place?


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Rusty flows

This little stream shows up the colours deposited by oxides and other compounds as it runs from a fumarole on the crater floor towards the sea. A magic carpet.
Next to it runs another little stream that is almost clear of colour; its source is much higher in the crater wall and it is not filled with material from fumaroles and upswellings directly above the magma chamber.
Both the streams are acidic, however, with a pH of 2 or 3, about the same as your stomach. You wouldn't want to drink it.

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Ever changing

This is the mud in one spot in the crater, part of a larger mud pool that is constantly in motion, and the whole crater of mud is changing shape almost daily. We saw mud pools at Orakei Korako and in Rotorua but because of the drought they were pretty dry. Here on Whakaari not only is there plenty of rain, but steam feeds these pools from below.
White Island is a place to teach you that the rocks themselves are alive, that all of the environment is dynamic, and that the equilibrium of terra firma is pretty fragile. The colours, smells and shapes here are all in flux, and the great majority of them are chemical, created by minerals and water, rather than the algae and other life-forms that visibly push change in most places.

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It's pretty big

This picture gives some idea of the scale of the place. The crater lake is hidden behind rocks against the back wall. There is a little man on the track (a very committed photographer, closely watched by a patient guide).
This photo is taken from the highest spot on the crater floor, about a third of the way from the back wall to the landing place.

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Crater lake

At the back of the crater floor is a smaller crater. This was formed by a major explosion in 1976, which left a cone about 120m deep. This gradually got filled up by rubble (both ejecta and stuff washed off the crater walls by rain), ash and smaller stones. Inevitably the blocked vent exploded again.
There were then heavy rains in 2000 which left a small puddle over the vent. This was expected to disappear. Instead, it has become a permanent feature, inasmuch as anything is permanent here. The lake is fed by steam coming out of the vent which condenses on contact with the water. From the surface, water is lost in steam or ordinary evaporation, but re-fed by rain water.
The lake is not salt, but has a pH of -0.5. That's serious acid, of the sulphuric and hydrochloric variety. The day we were there it was still, but sometimes it is belching steam which is very unpleasant to breathe. Certainly this was an area where the gas masks came in handy.

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Getting close to the sulphur

All across the crater floor are humps of materiel, left by eruptions and landslides. The hot steam finds a way through these, creating fumaroles which deposit the sulphur and other compounds. The surface of these mounds is a thin crust, which we were continually warned not to walk on. Apparently a couple of weeks before a tourist ignored this and found himself ankle deep in very hot mud.
You can put your hand over this vent (which is close to the relatively stable path), and feel the heat; you can't get really close because the steam is scalding.
All this sulphur? Yes: White Island is a smelly place. It reeks of sulphur compounds. It is a bitter, acrid smell, though, quite distinct from the rotten eggs steam that sometimes hangs over Rotorua.

Places and people

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