Geniusfind Science > Earth Sciences

http://search.usgs.gov/ - This is the homepage for the US Geological Survey. They have a searchable directory focusing on earth sciences. You can also get a state by state rundown of earth science info.
http://www.scinet.cc/directory/Science/Earth_Sciences/ - SciNet comes through for us again with an excellent earth science directory. SciNet: Earth Science has a multitude of links for you to follow.
http://www.geo-guide.de/ - Geo-Guide has a listing of resources for the earth sciences, and from this page you can access a few search engines on the subject, too.

http://www.geo.ucalgary.ca/VL-EarthSciences.html - The WWW Virtual Library: Earth Sciences has a long list of user-contributed earth science links. They have three sections: one organized by current events, another by country, and one more by organization.
http://www.ulb.ac.be/ceese/meta/cds - This is a list of over 600 environmental directories. And that's it.