tc from a place called Bruneau-Jarbidge in sout Ida tkilled t big enougo leave an asen feet deep almost a tern Nebraska. It turned out t under tern United States t spot, aclysmically every600,000 years or so. t sucion over 600,000 years ago. t spot isstill t Yelloone National Park.
e knotle about is fairly remarkable tot Ford t tinents moveabout on tion.
“Strange as it may seem,” e Ricand tribution of matterin terior of tter tand terior of th.”
tance from to ter is 3,959 miles, w so very far.
It ed t if you sunk a o ter and dropped a brick into it, it ake only forty-five minutes for it to ttom (t t point it rat).
Our otempts to penetrate to indeed. One or to a dept most mines on Eart a quarter of a mile beneat yet even come close.
Until sligury ago, -informed scientific minds kneEarterior muc a coal miner kne you could digdoance and t rock and t it. t named R. D. Oldemala, noticed t certain srated to a point deep an angle, as if tered some kind ofbarrier. From t ter a Croatianseismologist named Andrija Moudying grapiced a similar odd deflection, but at a s and tely belole; tinuity, or Mo.
e o get a vague idea of terior—t really until 1936 did a Danisist named Inge Leudyingseismograp t o be solid and an outer one (t Oldected) tis t to be liquid and t of magnetism.
At just about time t Leanding of terior by studying ts at Calteco make comparisons bet. ter and Beno Gutenberg, t o do at once as Ric o do ereit fello al“tude Scale.”)ter scale ood by nonscientists, ttle less so nos early days o Ricen asked to seeed scale, t rary measure of tremblings based on surfacemeasurements. It rises exponentially, so t a 7.3 quake is fifty times more poimes more pohquake.
At least tically, t for an earto t, a lo. t says not damage. A magnitude 7quake le—say, four cause no surfacedamage at all, ation. Mucoo, depends on ture of tion, ty of aftersting of ted area. All t t fearsome quakes are not necessarily tforce