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Fatal Warning! US oil spill explained! BEFORE it did EQ Volcano’s! Islands oil Rigs sinking

Post-glacial rebound (or Glacial Isostatic Adjustment) produces measurable effects on: (i) Vertical Crustal Motion, (ii) Global sea levels, (iii) Horizontal Crustal Motion, (iv) Gravity field, (v) Earth’s rotational motion and (vi) State of stress and earthquakes. Studies of Glacial rebound give us information about the flow law of mantle rocks and also past ice sheet history. The former is important to the study of Mantle Convection, Plate Tectonics and the thermal evolution of the Earth. The latter is important to the study of Glaciology, Paleoclimate and changes in Global Sea Level. Understanding postglacial rebound is also important to our ability to monitor recent global change.
To form the ice sheets of the last Ice Age, water is taken from the oceans through evaporation, condensation as snow and then deposited as ice in high latitudes. Thus global sea level would fall during glaciation.

The ice sheets at the last Glacial Maximum were so massive that global sea level fell by about 120 metres. Thus continental shelves were exposed and many islands became connected with the continents through dry land. This was the case between the British Isles and Europe, or between Taiwan, the Indonesian islands and Asia. Most important is the existence of a land-bridge between Siberia and Alaska that allowed the migration of people and animals during last glacial maximum.[3]

The fall in sea level also affects the circulation of ocean currents and thus has important impact on climate during the Ice Age.

During deglaciation, the melted ice water returns to the oceans, thus sea level in the ocean increases again. However, geological records of sea level changes show that the redistribution of the melted ice water is not the same everywhere in the oceans. In other words, depending upon the location, the rise in sea level at a certain site may be more than that at another site. This is due to the gravitational attraction between the mass of the melted water and the other masses, such as remaining ice sheets, glaciers, water masses and mantle rocks[3] and the changes in centrifugal potential due to Earth’s variable rotation.[11]
Gravity field
Ice, water and mantle rocks have mass, and as they move around, they exert a gravitational pull of other masses towards them. Thus, the gravity field, which is sensitive to all mass on the surface and within the Earth, will be affected by the redistribution of ice/melted water on the surface of the Earth and the flow of mantle rocks within.

Today, more than 6000 years after the last deglaciation terminated, the flow of mantle material back to the glaciated area causes the overall shape of the Earth to become less oblate. This change in the topography of Earth’s surface affects the long wavelength components of the gravity field.

The changing gravity field can be detected by repeated land measurements with Absolute Gravimeters and recently by the GRACE satellite mission.[12] The changing long wavelength components of Earth’s gravity field also perturbs the orbital motion of satellites and has been detected by LAGEOS satellite motion.[13]

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