grace. see movie free air gravity anomalies derived from radar altimetric determinations of geoid...
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GRACE
See movie
Free air gravity anomalies derived from radar altimetric determinations of geoid height
milligals
Bathymetry determined from satellite radar derived gravity plus shipboard measurements
Major types of isostatic compensation
1. Airy: crustal root compensates elevated topographya. Ocean-continent crustal thicknessesb. Majority of variations in elevations on continental
mountain beltsc. Oceanic plateaus
2. Thermal: elevated topography a result of thermal expansiona. Ocean ridge systemb. Basin and Range
3. Flexural isostasya. Bending of the lithosphere: oceanic trenchesb. Regional isostasy
crust
mantle
Airy isostasy
crustal thickening
crust
mantle
Airy isostasy
topographic “load”
compensating root
Simple Airy isostasy is dealt with in more detail ingrav_anom.ppt
crust
mantle lithosphere
mantle athenosphere
1300 C
Temperature, degrees C
0 1300
50
100
150
200
Thermal isostasy
A
B
Lithospheric
thinning
uplift from thermal expansion
A
B
Thermal thinning and uplift are dealt with in more detail inthermal.pdf
Outstanding continental examples of thermal or Airy isostasy
thermal
AiryAiry