Sand devil length and at least in weight. The sand devil is found in the northwestern Atlantic Ocean from Massachusetts to the Florida Keys, where it is fairly common. It also occurs in the northern Gulf of Mexico, and there are additional unconfirmed records from Cuba, Jamaica, Nicaragua, and Venezuela. The southern extent of its range is uncertain due to confusion with the disparate angelshark ("S. heteroptera") and Mexican angelshark ("S. mexicana"). This bottom-dwelling shark is found over sandy or muddy bottoms on the continental shelf and slope. Off the eastern United States, the sand devil has been documented to migrate seasonally.
Ocean island basalt much closer to the Earth's surface in the asthenosphere. The existence of mantle plumes and hotspots has, however, been hotly debated since they were first proposed in the 1960s and 1970s. There are various sources identified for ocean island basalt magma in Earth’s mantle. These mantle sources are inferred from differences in radiogenic isotope ratios that magmas inherit from their source rock. Sources have been defined from a combined analysis of strontium (Sr), neodymium (Nd) and lead (Pb) isotopes. The sources as defined by radiogenic isotopes are: Ocean island basalt Ocean island basalts (OIB) are basaltic rocks found on many