单词：magnetite-taconite
[网络] 磁铁矿-铁燧岩
单词：magnetite-taconite 相关文章
Sierra Leone hopes to become Africa's biggest exporter of iron ore with the opening of a new mine in the central Tonkolili district. Geologists say the new mine holds more then five billion tons of iron ore. Before mining can begin at Tonkolili, geol
发表于:2019-01-13 / 阅读(102) / 评论(0)
VOA标准英语2010年(二月)
VOA标准英语2010年(二月)
By analyzing different samples of lava, Herrero / Bervera has built up a picture of how the filed has changed since long before humans were around. They are actually the recorders of the Earth's magnetic field in hundreds of years, thousands of years
发表于:2019-01-22 / 阅读(125) / 评论(0)
自然百科2011年
自然百科2011年