Page 35 - Whole Earth Geophysics An Introductory Textbook For Geologists And Geophysicists

17 is a not for of
eseydsoylyy *} with a 150'to mantle tem- pres- as early magnetic mid- at 1966). The seis- outlin- Bands
System to increasing the surface to from III) The [V) The outer core, lower the the at liquid depth. The exists material the in theory did geological and of and form crust (Vine, acceptable mechanism worldwide bands narrow 1968). trenches, where

Lithosphere/Asthenosphere Hard Solid Five zones of differing physical state relate lithosphere is a hard solid, extending uppermost mantle. II) The asthenosphere is solid upper part (from about below, the lower part gradually becomes harder to 700 km depth. that km 700 to is core outer the km 5100 and 2900 same the that crust originated Earth’s tectonic plate of number vast a when

= above and material from 2900 to 5100 km depth, is liquid. V) The solid inner core extends from about 5100 to 6300 km depth. 350 of depths of material between however, SYSTEM of acceptance however, the in made basaltic away older spreading” oceanic new earthquakes (Isaacs, plates regions in another.
Earth Earth. (P) with depth. I) The to the lower mantle (or mesosphere) is a hard solid, extending from about 700 to 2900 km depth. below (iron-rich) encountered center, displacements widespread 1970’s, were the that progressively leaving most that lithospheric depths beneath

the includes the crust and great Earth’s lateral and and suggest “sea-floor reveals to great descend

of melt. Relative is a soft (plastic) solid; the so heavy pressures near LITHOSPHERE/ASTHENOSPHERE 1960’s observations are of apart, of extend to
Divisions (Physical State Due to Increasing Temperature and Pressure with Depth) Modern divisions of the pressure and (T) km depth. It becomes solid. The and great so is core. inner large about Development the until geophysical patterns and ridges concept drift to network boundaries earthquakes appears plate

Modern 2.4 FIGURE temperature 100 to 200 about slight amount of partial 400 km depth) pressure hard a peratures sure solid Ideas 1900’s. occur anomaly ocean resulting continents mograph the ing one

to changes in oxygen), with densities of Earth's volume, of its 1% about 30 to 2900 km of Earth's volume, 68% of its has an average density of 16% of has core into spheres three the 2.3). (Fig. center chemical composition, in resulted res- finer division modern more state (hard solid, are lithosphere, the inner core (Fig. 2.4). divisions Maj

zones of differing density correspond and in silica (silicon less is than 2% from Extending magnesium. It comprises 82% nickel. [t Earth at 6300 km. The differentiated Earth the concentrated toward in changes to 1960's the in spheres, A three according physical their to recognized thus and outer core, of date. out not is scheme and crust the

Earth minerals rich 70 km. It and iron in to 5.8 g/cm?. the center of the to century, material correspond core. seismographs better the within spheres zones Five (or mesosphere), classical the boundaries, between The modern conditions Silicates comprising the of part top also are mantle depths At melting, partial

Tectonics the of Classical divisions of the Earth. Three 1) The crust is mainly thickness between 2 and from 3.3 mass, 3) The core is predominately iron, with other heavy elements like from 2900 km of its mass. the 20th denser the density in and mantle and more velocities wave the three liquid). or lower mantle that 2.3). (Fig. under 2.4). the uppermost lithosp

Plate Divisions (Density Differentiation due to Changes in Chemical Composition) mass. 2) The mantle is silicate minerals rich of part density, to differences crust, of of seismic of portions solid, soft illustrates chemical core the chemicals (Fig. Earth forming rigid, the the of undergo

Chapter2 Classical 2.3 chemical composition, between 2 and 3 g/cm’ and depth, mantle density increases 10.8 g/cm? and extends Earth’s volume and 32% early the in according Drastic the defining Divisions The installation olution describes relatively asthenosphere, Fig. 2.5 along still are and mantle of state those the within they are silicates of remainder materials

16 FIGURE about Modern
*