Silica Steps in a Steaming Fern Landscape

Silica Steps in a Steaming Fern Landscape is an original illustration set in Rotorua Geothermal Region, New Zealand. It lies in mid-latitudes, where the climate is oceanic — mild, wet through the year.

White silica terraces descend in broad steps beside turquoise hot pools and a gray bubbling mud basin. Clean columns of steam rise between low fern and kānuka scrub, creating stark patches of barren mineral ground within the otherwise cool, green North Island landscape.

How do white mineral terraces and bubbling mud form within cool green fern scrub?

Groundwater heated by the Taupo Volcanic Zone rises through fractures carrying dissolved minerals and volcanic gases. Cooling alkaline water deposits silica layer by layer to build pale terraces, while acidic fluids alter rock into clay that bubbles as gas escapes through mud pools. The close mixture of sinter steps, hot water, mud, steam, and specialized low vegetation identifies New Zealand's Rotorua geothermal region.

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