Geobulletin alpha

Source info:

Author:
Date:	2014-12-19 01:39:20
Blog:	AGU Meetings
URL:	http://blogs.agu.org/geospace/2014/12/19/rocks-larger-faster-crumble/

Summary:

Sooner or later, mountains crumble into boulders, boulders crumble into rocks and pebbles, and so on, until wind and rivers carry sand and dust into the ocean, completing the geologic rock cycle. "But how [rocks] go from the mountain into that ocean bottom, that's what is not understood very well," said Jaakko Putkonen, a geologist with the University of North Dakota. Scientists from UND and other institutions discovered that chunks of rock break off of boulders in Antarctica once every 1,900 years on average, and those smaller chunks break apart once every 510,000 years. Putkonen thinks that heat flow through rocks might be responsible for the dramatic difference in how fast bigger rocks crumble compared to smaller rocks. Knowing how fast boulders break down into smaller and smaller chunks will help geologists understand how the mountains crumble to the sea everywhere.

Content analysis:

Geographic context:

Location	Country	Latitude	Longitude
Antarctica	AQ	-81.5	0
University of North Dakota	US	47.9233	-97.0775

Keywords:

2014 Fall Meeting, Antarctica, average, bigger rocks, boulders, crumble, dramatic difference, dust, fast boulders, geologic rock cycle, geologist, geologists, heat flow, Jaakko Putkonen, mountain, North Dakota, ocean, pebbles, rivers, rock break, rocks, sand, Scientists, smaller chunks, smaller rocks, UND, University, wind