Scientists have long believed that lava, erupted from certain oceanic volcanoes, contains materials from the early Earth's crust. But decisive evidence for this phenomenon has proven elusive. Now, new research from a team of researchers including the Carnegie Institution's Erik Hauri has demonstrated that oceanic volcanic rocks contain samples of recycled crust dating back to the Archean era 2.5 billion years ago.
Fonte: http://www.nsf.gov/news/news_summ.jsp?cntn_id=127848&org=NSF&from=news
