yael c. agmon

Subterranean Channels: Processes at play in the creation of multiple water channels in the rock
The Snake River Plain, Idaho

#Architecture of Nature #Architectural Analysis #Representation
The Cooper Union, New York

The interaction between the different states of materiality and their geological formations is explored through the relatively unstable geo-morphology of the Snake River Basin. The way water, and previously lava, penetrates through the labyrinth of the rock mass reveals the extremely complex structure of the landscape.

A dynamic relationship between solids and liquids is exposed. The viscous lava melts the rock, gradually solidifies and transforms into a different type of rock. Though this volcanic rock blocks large amounts of water flows, it allows for the accumulation of a great body of water within its cracks. The water preforms endless metamorphoses as it evaporates, condensates, cling to each other, and split to single molecules; eroding its way through the rock.

The processes of material formation and their interactions are at play in completely different scales. The enormous system of this aquifer is nothing but an echo of a colossal volcanic engine buried underground.

Geo-morphological processes

About 16 Million years ago, a bulbous plume head, known as the Yellowstone hotspot, intercepted the base of the lithosphere and mushroomed out, resulting in widespread magmatic and tectonic activity centered on southwest Idaho. Gradually transforming into a chimney, the mantle melt penetrated through the boundary of the Earth’s crust and spread outward. By the motion of the North American plate to its current location in NW Wyoming, the Yellowstone hotspot melted hundreds of miles of rock mass and left in its wake a series of calderas and various volcanic features.

The interaction between the stationary hotspot and the moving plate generated a series of geological transformations and formed belt-like systems of tension cracks. As a result, a flat volcanic landscape surrounded by a crescent of mountain ranges was formed, known today as The Snake River Plain. Simultaneously, the Snake River itself has been carved out along with a few lakes that had dried by now.

The morphology of the landscape stimulated a moisture ‘channel’ originating from the Pacific Ocean, which allows for the accumulation of adiabatic clouds in the region. As the mountain ranges surrounding the plain block their movement, the clouds are forced to pour a tremendous amount of precipitation over the landscape.

The geo-morphological processes and resulting features, the climate conditions and the geological structure of the basalt rock, generated an enormous aquifer beneath the plain, one of the largest in the North America.

Water flow

The water of the aquifer flows between the grains of sediments and in the cracks of the basalt mass, generally from the recharge zone along the mountain crescent toward the Snake River at Thousand Springs.

At times, eruptions and basalt flows changed the course of the Snake River, damming and forcing it to find new routs towards southwest, eventually separating it from the streams and rivers coming from the north-eastern part of the basin. These rivers disappear in the middle of the plain, dissolve into smaller portions of water and start making their way through the labyrinth of the basalt rock, and connect back to the Snake River at Thousand Springs.

Although the shortest distance between two points is a straight line, the easiest path for the water flow in the aquifer is anything but straight. Characterized by high tortuosity, the water molecules in the aquifer take a convoluted path to wave in and out, above and below the broken pieces of rock mass. Crossing between 1-10 feet per day, a full journey probably takes about 150-250 years.