These include a 150% "net benefit requirement" for water quality which, Hunt said, would result in a long-term reduction of sediments entering the reef marine park from land-based sources.
Earth's history is marked by a number of major mass extinctions of species, triggered by volcanic eruptions, asteroid impacts and release of methane from sediments.
Researchers have re-created reef ecosystems in tanks – complete with corals, sediments, rocks, fish, crabs and plants – and then subjected them to the kinds of temperatures and carbon dioxide concentrations expected near the end of this century.
When the falling rocks hit the delta they destabilised the sediments and caused the canyons to collapse.
But a paper just published in Nature Geoscience by Dr Kremer and her colleagues offers a different and more worrying explanation.Canyon diaboloDr Kremer thinks that the rocks crashed down onto soft sediments which had accumulated at the river mouth because of the slowing of the river's flow when it enters the lake.
These sediments form an underwater delta that has several canyon-like channels.
If the lining of the well below the surface has been weakened, either by the initial blowout or by the erosive power of the millions of barrels of oil that have flowed through since, that increase in pressure could cause the well to spring a leak below the seabed, letting oil and gas escape out into the sediments through which the well is drilled.
They are well preserved, and encased in sediments that allow uncommonly precise dating.
That is one reason why the Earth's deltas, home to hundreds of millions of people, are eroding away faster than they can be replenished.Geologists care about sediments, hammering away at them to uncover what they have to say about the past especially the huge spans of time as the Earth passes from one geological period to another.
Research on sediments by the Scripps Institution shows that the collapse was in fact a natural oscillation.
And heavy oil tends to stick to ocean sediments.
