Untitled Document

TABLELANDS, NEWFOUNDLAND

 

LOCATION
The Tablelands, a geologic formation of global significance, sit on the west coast of Newfoundland, inside Gros Morne National Park. Due to their lack of vegetation and unusual shape (at right), the Tablelands stand out for miles around, drawing tourists and geologists alike. We spent the warm, sunnny afternoon of our seventh day examining the rocks and taking in the desert-like landscape, and resisting the collectine urge!

Geologically speaking, the Tablelands lie in the Western Zone of Newfoundland, not far from Green Gardens Trail (visit our Green Gardens Trail Page). They rise above many of the nearby mountains, remaining snow capped throughout most or all of the year.

What we saw of Geologic Importance
The Tablelands--these dirty brown rocks--originated deep in the Earth! Though formed by the crystallization of molten magma within the mantle (the layer below the Earth's crust and above the core), these rocks have undergone millions of years of change and transformation, and are therefore labled metamorphic rocks. Since crystallization, the Tablelands have been flowing and changing, like a plastic under high temperatures and pressures.

But the dusty brown color is just a cover-up; the weathered surface hides a banded composition of pyroxene, olivine, and serpentine. When split with a rock hammer and chisel (or the sheer strength of our geologic minds') a dark green interior is revealed.

 

Olivine and Serpentine
When altered, olivine (a high temperature magnesium silicate) breaks down to form serpentine (a low temperature, hydrous magnesium silicate). Locally, the serpentine occurs as asbestos. The iron is these samples accounts for the rusty brown weathered surface; oxidzed iron creates the rust color.

Some of the serpentine we observed displayed a more scaly texture and is called lizardite. This multi-colored photo to the right looks more like an intricate mosiac than a naturally formed rock. When splashed with water, a shiny, almost slimy, texture appears, making this rock's name highly appropriate.

Vegetation
While bedrock almost always plays a significant role in the nature of a landscape, seldom is it so clear as at the Tablelands. Upon visiting this area, one immediatly notices the sparse vegetation; the dusty texture and brown color of the rocks offer a desert-like, almost moonscape, scene.

Magnesium and iron cannot support life as well as other more nurishing elements, and therefore account for the relative paucity of plant-life. Among those plants that can survive such harsh conditions is the carnivorous pitcher plant (sarracenia purpurea), which normally grows in upland bogs. This plant, the provincial flower of Newfoundland, survives by absorbing nutrients from captured prey. Insects are lured to the pitcher plant's liquid and trapped by small hairs that line the inside of the "pitcher."

CLICK ON ANY OR ALL PHOTOS FOR A LARGER IMAGE!