Continental drift orogeny at the boundaries of convection cells. By 1967, barely two decades after discovery of the mid-oceanic rifts, and a decade after discovery of the striping, plate tectonics had become axiomatic to modern geophysics. In addition, Marie Tharp, in collaboration with Bruce Heezen, (who initially ridiculed Marie's observations that her maps confirmed continental drift theory), provided essential corroboration, using her skills in cartography and seismographic data, to confirm the theory. Evidence for the movement of continents on tectonic plates is now extensive. Similar plant and animal fossils are found around the shores of different continents, suggesting that they were once
Drift pin Drift pin In metalworking, a drift pin, drift pin punch, slave pin, simply drift, or even pokey bit is the name for a tool used for enlarging holes, or aligning holes prior to bolting or riveting metal parts together. A drift pin is not used as a punch in the traditional sense of the term. A drift is constructed as a tapered rod, with the hammer acting on the large end of the taper. The tapered end of a drift punch is placed into the semi-aligned bolt holes of two separate components, and then driven into the hole. As it