PLANETARY GEOLOGY

Discuss the factors that affected the geologic processes and formations of the planetsOutline the information in the 6 slides

Use Chapter 9, sections 9.1 and 9.2 to add further detail.

Highlight the detail.Refer to your vocabulary to be sure you understand the

concepts

PLANETARY GEOLOGY

PLANETARY GEOLOGY

DifferentiationGravity pulleddenser materialsto the center.

Inside the planetsare layers controlledby density.

Core highest densityiron & nickel

Mantle moderatedensity of mineralsof silicon and oxygenand other elements

Crust/Lithosphere: Lowest density rigid rock “floats” on the softer mantle

The thickness of each layer varies with each planet.

PLANETARY GEOLOGY

Geological Activity comes from:• Heat of Accretion of

colliding planetesimals • Heat from differentiation• Heat from radioactivity

Interiors cool off by• Convection• Conduction• Radiation

The smaller the planet the faster it cools

PLANETARY GEOLOGY

Planetary surfaces are shaped by

• Impact Cratering• Volcanism• Tectonics• Erosion

Convection currents move the tectonic plates and create geologicfeatures

PLANETARY GEOLOGY

If a planet is too small like Mars or Mercury or The Moon, the interior will cool too rapidly tohave volcanism and tectonics.

Other Factors of Planetary Geology:Distance from the Sun

PLANETARY GEOLOGY

Planets too close losetheir atmosphere andare too hot for precipitationto cause erosion

Planets too far awayare too cold for evaporationand condensation forcloud formation. Noweather and no erosion

PLANETARY GEOLOGY

Planetary RotationThe faster the rotation the more rapid the wind and weather and erosionEarth rotates on its axis every 24 hours while Venus takes 234 days.