see the diagonal line that runs through the orchard in the incredible photo above? that's the san andreas fault - a point where the edges of 2 tectonic plates meet - producing a visible displacement amongst the rows of trees. when they were planted years ago the rows were straight, but as the 2 ginormous land masses moved in opposite directions and rubbed against each other over the years the orchard was split. the top half of the field sits on the pacific plate, the bottom half on the north american plate.
here's another fault line. it's called álfagjá rift valley and can be found in reykjanes, iceland. at one point along the rift the two plates (eurasian and north american), have been connected by the miðlína bridge, seen in the photo. on the left: eurasia, on the right: north america.
another frightening tectonic rift, thingvellir, iceland.
the incredible walls of a huge tectonic crack in aguateca, used as a defense by the mayas. the rift is 1 ½ km long and measures between 2 and 10 metres wide.
tectonic rifts of this magnitude usually develop at a rate too slow for the human eye to notice. however back in september 2005, a 60km long collection of cracks opened up in ethiopia's afar region, all over the space of 3 weeks. over the next year the fissures widened until in september 2006 a volcanic vent opened up and blew open a ½ km long crack. the area in question - the afar triangle - is a meeting point of 3 tectonic plates and geologists predict that soon (by soon they mean approximately 10 million years) it will sink and become a new ocean basin, splitting the continent apart.
a section of the cracks that appeared in 2005
the volcanic vent that opened up in 2006, surrounded by ash
a close-up of the huge vent
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