Tax returns and supporting documentation. The IRS has three years to challenge your tax returns, so you must keep them at least that long. It's wise to keep tax returns for at least six years, because if the IRS suspects you may have under-reported income, it has six years to challenge returns.
How is the Earth's crust related to tectonic movement? The convection currents in tectonic plates occur in the geosphere. The radioactive decay of elements is responsible for the heat deep within the earth, and this results in the creation of magma. Magma is a type of material that can be semi-fluid or completely fluid.
Ocean currents depend on the geometry of the oceans and this is controlled by plate tectonics. Hence, over geological timescales the movement of plates and continents has a profound effect on the distribution of land masses, mountain ranges and the connectivity of the oceans.As a consequence, plate tectonics has a very direct and fundamental influence on global climate.iven the clear link between ocean circulation and climate, and the similar timescales of global climate change and plate motions, it is inescapable that one of the chief controls on long-term changes in the global climate must be plate tectonics.