Gaseous Earth

New Zealand is a work in progress. The Pacific and Australian tectonic plates meet and grind against each other along the axis of the two islands that make up Aotearoa. Geologists have measured the movement of the rock in the South Island to be about two millimeters per year.

As at many seams between the plates that cover the earth like a patchwork, in New Zealand there is volcanic activity. Rotorua, a town in the centre of the North Island, is a site of such activity. As recently as 2001 the local volcano erupted and produced new holes through which bubble the steam and minerals from under the earth’s crust.

We visited a local reserve which boasts the awe-inspiring results of continued geothermal activity: Waiotapu. Wandering along the prescribed paths (moving off the paths means stepping onto “unstable ground”) we were surrounded by ever-present wisps of steam spurting from the ground. Here and there the heat and pressure of the steam had eaten away the surface rock and collapsed the ground, leaving gaping craters. Where the earth had a high clay content the steam condensed and turned the dirt into mud; the super-heated gas and water from below bubbled up and made the dark brown ponds into gurgling orchestras of popping and belching. (I wanted to take my Chacos off and put my feet in the mud, but there was no place they’d let us do it. Sigh.)

As the steam condenses into water and runs along the surface of the ground it leaves behind mineral deposits. The least extravagant of these are the silicate shelves, long expanses of web-like white rock. In other places the rock is a bright orange crust surrounding a wide pool of deep blue with little bubbles rising up out of its depths. There is even one pool that is an opaque, fluorescent lime green colour (Kara, we thought of you at this one) due to its arsenic content.

Walking between these pools of vibrant coulour as warm mists blow across your vision and enshroud you in blankets of fog makes the whole experience like some sort of wonderland. The only drawback to all this stunning scenery and activity is that the whole place reeks of sulfur. At times it’s like standing in a big vat of rotten eggs. A small price to pay (over and above admission price) for the spectacular show.

We got a good dose of the tourist side of geothermal activity. The industrial side is the energy production that can be wrought from the earth’s disgorgement of heat and steam. Geothermal power production makes up a significant chunk of New Zealand’s total national power production. We got a show of heat, bubbles, an colour, while New Zealanders get those and some energy to boot. Good deal.

God did a good job with the earth’s design; Rotorua is a good place to enjoy that design. We recommend it if you’re ever on New Zealand’s North Island.

~emrys