SEISMOLOGY Flashcards
is the study of the generation, propagation and measurement of seismic waves through earth and the sources that generate them.
SEISMOLOGY
The earth’s shape is an
OBLATE SPHEROID
the average specific gravity
of earth is about
5.5
the outer part of the earth is where the life exist.
CRUST OR LITHOSPHERE
is a 2900 km thick layer
MANTLE
Upper Mantle reaching a
depth of about 400 km made of
OLIVINE AND PYROXENE
Lower Mantle made of more
homogeneous mass of
MAGNESIUM, IRON OXIDE AND QUARTZ
SPECIFIC GRAVITY OF MANTLE
5
Core has a radius of
3470 km
INNER CORE HAS A RADIUS OF
1370 Km
the core is composed of
molten iron, nickel, sulfur or silicon
proposed the hypothesis that the continents
had once formed a single landmass before breaking apart and drifting to their present locations.
German Scientist Alfred Wegener (1915)
explains that the lithosphere is broken into seven large (and several smaller) segments called
PLATES
He proposed that a large continent termed Pangae existed in earth around 200 million years ago and was surrounded by an ocean called.
PANTHALASA
WHAT IS THE CONTINENTAL SIZED PLATES
African, American, Antarctic, Indo-Australian, Eurasian
and pacific plate
are areas along the edges of plates move apart from each other
SPREADING RIDGES OR DIVERGENT BOUNDARIES
are formed where the two plates move toward each other. In this process, one plate could slip below the other one or both could collide with each other.
CONVERGENT BOUNDARIES
These boundaries are created when either oceanic lithosphere subducts beneath oceanic lithosphere (ocean-ocean convergence), or when oceanic lithosphere subducts beneath continental lithosphere (ocean-continent convergence).
SUBDUCTION BOUNDARIES
When two plates with continental lithosphere collide, subduction ceases and a mountain range is formed by squeezing together and uplifting the continental crust on both plates,
COLLISION BOUNDARIES