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Important processes:
• Tectonism• Volcanism• Cratering• Climate links
Impact craters Pancake domesShield volcanoes
Class 14: Topography,Tectonics, Volcanism
Magellan Mapping of Venus
SAR image
topography
gravity
Resolution & Topography
Height above mean (km)
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Magellan Gravity Data
Magellan-measured Gravity
milligals
Topography of Venus
Ishtar Ovda/Thetis
Atla Beta
Lavinia
Highlands: Atla
Ozza Mons
Sappas Mons
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Plains: Lavinia
Radar Imaging
flatsurface
forest cropland mountains roughsurface
city
surfacetype
RadarImage
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Example: Radar Image
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Stuff about Radar Images
slopingsurface
flatsurface
roughsurface
Example: Radar Image
Radar Image Properties
Surface
(reflective stuff)
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Plateaus: Ishtar
Maxwell Montes
Plateaus: Thetis
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tectonics: crustal stresses & resulting features (forces) (faults, folds)
Tectonics & Deformation
stresses can push crust together (compression),
building mountains
stresses can pull crustapart (extension) ,
making cracks/valleys
Appalachian Mts. Ceranius Valleys (Mars)
compression extension
Rock Strength
stronger
Brittle and Ductile Deformation
Extension(normal faults)
Transform(strike-slip faults)
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Brittle and Ductile Deformation
50 km
Venus: Folds & Mountain Belts(Earth)Akna Montes
Ishtar
Venus: Faults
Gumby
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1
23
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Venus: Rifting
25 km
Venus: Volcanoes
Maat Mons
caldera
main volcanic edifice
lava flowsextending away
from edifice
Size & Shape
volatiles releasedinto atmosphere
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Locations
Shield Fields
Volcano Flows