What is below the sands of the seabed ? ?

Question

if you dig down,how far before you hit "normal"earth?

Answer 1

This will depend hugely on the environment:  Sand carried down to the sea by rivers, or derived from the breakup of shells, is reworked and sorted by wave energy, creating beaches. However the depth to bedrock will depend on whether you are on a prograding delta for instance, when the beach sands will be underlain by thick successions of clays and other sands, or on a rocky steep shoreline, when the beach will be underlain by hard rocks, possibly not far below the surface.  

What is 'normal earth', come to that - this also depends on the nature of the bedrock, the climate, the vegetation etc.  

Sands are usually restricted to the parts of the seabed near the coast where there are high waves and tide energies, and further out where it is still, there will be silts and clays deposited.

Answer 2

Well it depends where on the sea bed you look at.

In the middle of the pacific you wouldn't find sands, you would find muds and clays as the current velocities are too weak to carry larger sand particles.

Under this top layer you would find other layers of sediment.

The composition of these layers depends on the conditions they were deposited in.

For example. The chalk cliffs in Dover, England would have been a layer  deposited under calm, steady conditions in deep clear water with little/no input of sediment.

The deeper into these layers you go the more 'rock like' they become due to extreme pressures subjecting them to lithification (The process that turns loose sediment into rocks.)

To find a 'normal' layer of earth I suppose you are talking about the igneous basalt which makes up the whole of the oceanic crust?

Well it depends on how far away from the mid ocean ridge (In the case of the Atlantic) you go. The crust by the ridge would be 'normal' earth and the further away from this you go the older the crust becomes. This means it has had more time for sediment to be deposited on top. Hiding the crust away.

Answer 3

The somewhat rough uncovering of Norway's first dinosaur happened in the North Sea, at an entire 2256 metres below the seabed. It had been there for nearly 200 million years, ever since the time the North Sea wasn't a sea at all, but an enormous alluvial plane.

It is merely a coincidence that the remains of the old dinosaur now see the light of day again, or more precisely, parts of the dinosaur. The fossil is in fact just a crushed knucklebone in a drilling core -- a long cylinder of rock drilled out from an exploration well at the Snorre offshore field.

Norway's first dinosaur fossil is a Plateosaurus, a species that could be up to nine metres long and weigh up to four tons. It lived in Europe and on Greenland 210 to 195 million years ago, at the end of the Triassic Period.

The Plateosaurus at the Snorre offshore field had a hollow grave. The fossil, which was found 2256 metres below the seabed, represents the world's deepest dinosaur finding. But it is by no means certain that the record-breaking knucklebone is a rarity down there in the abyss.

In fact, the old North Sea land was once a huge area where big rivers meandered through dry plains. Now the landscape has been compressed to form a pattern of fossil alluvial sand between banks of red shale.