More Snow, More Geology.

12-29-12 VERMONT: More snow today, at least six inches since mid-morning, with a few hours to go. It’s in the low twenties, but there’s no wind, so today’s snowshoeing was comfortable. Everything is white, and the snow is piled up on every surface.


Snowy Woods.

Whiteout-another six inches, so far.

Back to the pond ice—notice in yesterday’s pix the close up of the uplifted part of the ‘island’ that there is a crack through the middle perpendicular to the edge. When that small section of ice was bowed upwards it cracked because it can’t stretch or bend.

Now, if you will, think of the Mid-Atlantic Ridge, actually paired ocean-bottom mountain ranges located mid way between the Americas and Europe and Africa, extending almost from one pole to the other. The ridges are sliced by transform faults that cross the ridges at right angles to the segment of the ridge they intersect. [Wikipedia has nice articles on both the ridges and transform faults, and Google Earth shows them both.] If you visualize the ridges from the side running from pole to pole, it is obviously a long arc, not a flat line as it might seem when looking downwards at it, because the earth is a sphere. As the ridges are pushed upward and away from each other by the magma upwelling between the two ridges, the ridges, being solidified rock, are unable to stretch under this upward force and crack, forming the transform faults. As the ocean bottom is carried away from the spreading center these cracks are propagated and lengthened and extended. The ice demonstrates a mini-example of the formation of a transform fault.