OK you might be thinking "Big deal. rocks on the beach, so what?". This is pumice! You know, pumice -- the rock with all the holes that you can scrub across your foot callouses. This rock is abrasive on callouses but it is also so porous that it floats. On our sail last week we saw rafts of pumice floating on the sea. Some chunks have been floating for so long that they are encrusted with various algae and critters.
Oh, holey rock! |
This pumice must have traveled a crazy distance all the way across the Coral Sea. Based on recent wind directions, and some recent ocean current data
from http://www.oscar.noaa.gov/ |
it seems that the source volcano may be in the New Caledonia or Vanuatu areas about 1500 km to the east of us. Since ocean currents are often more complex than the straight line that I've drawn on the map below, the pumice could be from other sites and could have traveled even farther along a circuitous path.
We've seen some pretty cool things on the beach here, critters, shells and cuttlefish bones. But pumice! Wow! That is mind blowing.
UPDATE: News report this morning says that the pumice is from an eruption last year in the Kermadec Islands, north of New Zealand. That is 4000 km from us!
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