2010: the census of marine life is completed.
2011: Mariana Trench exploration
2012: first solo dive into the Mariana Trench. hope this helps. :)
True, though the Hadean period is one exception.
Air pollution. Cleaner burning than other fossil fuels, the combustion of natural gas<span> produces negligible amounts of sulfur, mercury, and particulates. Burning</span>natural gas does<span> produce nitrogen oxides (NOx), which are precursors to smog, but at lower levels than gasoline and diesel used for motor vehicles.</span>