Continental drift Permian era but failing to account for glaciation in India, Australia and South Africa. Geophysicist Jack Oliver is credited with providing seismologic evidence supporting plate tectonics which encompassed and superseded continental drift with the article "Seismology and the New Global Tectonics", published in 1968, using data collected from seismologic stations, including those he set up in the South Pacific. It is now known that there are two kinds of crust: continental crust and oceanic crust. Continental crust is inherently lighter and its composition is different from oceanic crust, but both kinds reside above a much deeper "plastic" mantle. Oceanic crust
One-name study One-name study A one-name study is a project researching a specific surname, as opposed to a particular pedigree (ancestors of one person) or descendancy (descendants of one person or couple). Some people who research a specific surname may restrict their research geographically and chronologically, perhaps to one country and time period, while others may collect all occurrences world-wide for all time. A one-name study is not limited to persons who are related biologically. Studies may have a number of family trees which have no link with each other. Findings from a one-name study are useful to genealogists. Onomasticians, who study