Maintained by the Max Planck Institute for Chemistry, the Geochemistry of Rocks of the Oceans and Continents database (GEOROC) contains about 70,000 sample analyses. These include whole rock, mineral, and inclusion data from seven tectonic settings such as convergent margins, oceanic plateaus, and ocean islands. The database can be queried by several criteria including a handy precompiled file...

The Nitrogen and Phosphorus Knowledge Web page is offered by Iowa State University Extension and the College of Agriculture. The publications page contains links to various newsletters, articles, publications, power point presentations, links to governmental publications, and more. For example, visitors will find articles written on phosphorous within the Integrated Crop Management Newsletter,...