Structure of the Earth the crust, upper mantle, lower mantle, outer core, and inner core. The geologic component layers of Earth are at the following depths below the surface: The layering of Earth has been inferred indirectly using the time of travel of refracted and reflected seismic waves created by earthquakes. The core does not allow shear waves to pass through it, while the speed of travel (seismic velocity) is different in other layers. The changes in seismic velocity between different layers causes refraction owing to Snell's law, like light bending as it passes through a prism. Likewise, reflections are caused by a large
Do Not Ask What Good We Do Do Not Ask What Good We Do Do Not Ask What Good We Do: Inside the U.S. House of Representatives is a 2012 book by the author Robert Draper and published by Free Press. It details the activities of Republicans and Democrats in the United States House of Representatives and the Senate during the first term of Barack Obama's presidency. The book was republished under the title When the Tea Party Came to Town. In order to research the activities and politics within the House of Representatives, Draper "embedded with new and senior House members" that had been elected in