Why is it easier to find fossils in young rocks than it is in very ancient rocks?

Answer 1

When a rock is left alone for along time things build up inside and outside and it gradually happens. Younger rocks haven't been around for quite as long so it hasn't built up as much to make it harder.

Answer 2

Geologically, you are talking about what is called the bias of the Recent. Only certain environments are likely to be preserved--wet ones, mostly, and particularly low disturbance deep marine environments. There is only an estimated 10% of the rock record preserved after 100 years; preservation gets even worse the farther back you go. Also, bioturbation, orthe movement of organisms through sediment, and taphonomy, or processes that happen after death like mechanical breakage can damage fossils.

Rocks are continually recycled by the earth, as well--subducted at subduction zones to be re-melted in the mantle and form new crust at spreading zones. When they go, their fossils go with them. Metamorphism also destroys fossils.

It is erroneous, however, to assume that this means that there is less life around than there was 500 million years ago. Occassionally, geologists find deposits called lagerstatten--these are exceptionally well preserved environments that show that there was a lot going on, even hundreds of millions of years ago. Examples include the Ediacaran Fauna and the remarkably preserved Archaeopteryx found in China in their deposit.

There are other Lagerstatten, too-the Burgess Shale has exceptional preservation. These provide a window into conditions at the time of deposition.

But basically, since most environments don't get preserved (unless they are quiet marine environments), and rocks have an increasing chance of getting severely metamorphosed or subducted as they age, it is easier to find fossils in young rocks.

Hope this helps!

Answer 3

I wouldn't want to sound like I think I know everything but there is no "young earth" explanation. As a geologist, I know this doesn't even come close to explaining the evidence. There are some very ancient rocks that have abundant fossils and there are young ones where they are very sparse or absent. Young rocks that are exposed on shore probably were created in a shallow marine environment or perhaps a terrestrial. In either case, you might expect to find fossils. Older rocks are more likely to have formed in a deeper marine environment where fossils may be more sparse. I don't think these scenarios would fit every situation but maybe it explains your observations.

Answer 4

It is not "easier" because in ancient rocks fossils do not occur. The Ancient rocks can be as old as 3.5 billion years or more, when there were no life on earth. As soon as life started, sometimes around 0.6 billion years, the fossilisation also started.
Another thing, you need a sedimentary rock of a suitable grain size to find a good fossil. Younger igneous and metamorphic rocks do not host fossils.

Answer 5

Young rocks are usually less altered by weathering, heat, pressure and all the other geological forces. Most very ancient rocks have been through the geological mill so fossils in them have been obscured.

In the most ancient times, there were no-multicelled animals so the only fossils were of bacteria or similar sized creatures, which are still difficult to see. Add this to the alteration of the rocks and it is not surprising that really ancient rocks might appear to lack fossils.

Though the Earth is thought to be a bit more than 4500 million years old, the oldest identified Earth rocks are about 4400 million years old. It may be that bacteria were around from about that time, but more certainly 500 million years later. However the earliest known multi-celled animals appear to be about 1200 million years old and are youngsters by comparison to bacteria.

http://www.nsf.gov/od/lpa/news/press/01/pr0102.htm

http://www.ucmp.berkeley.edu/bacteria/bacteriafr.html

Answer 6

Young earth explanation: Very ancient rocks were solid before the flood, so there is no way life could get into them to be fossilised.

Old earth explanation: very ancient rocks pre-date the existence of life. Slightly less ancient rocks may be contemporary with early life that had no hard parts and did not easily form fossils.

Answer 7

Very early:
Fossils are records of once living organisms. In very ancient rocks there are no fossils since the rocks were formed before life existed on earth.

Early:
Life first appeared as tiny, single cell organisms, making them hard to detect within a rock.

Later:
Over the eons, life evolved into multi-cellular organisms. The fossil record shows the existance, for example, of mollusk shells.

In last 100-200M years:
Eventually, bones evolved to provide structural support for animals. In "young rocks", these later life form's bones were preserved as mineral deposits in the shape of the original bones.

You can find more information on Wikipedia, the free, online encyclopedia at:
http://en.wikipedia.org/wiki/Fossil

Hope this helps!

Answer 8

Fossils are only found in sedimentary rock.
Nearly all the sedimentary rock and the fossils were laid down by the Global Flood, 4000 years or so ago.
Hence we see billions of fossils laid down by water, buried in sediment all over the world.

Evolutionists typically date the fossils from the rocks, and then date the rocks from the fossils! All based on uniformitarian *assumptions* that the world is billions of years old.

However the rocks were clearly not laid down slowly over millions of years since there are many tightly folded strata 9laid down and bent while wet); there are many polystrate fossils going between rocks allegedly millions of years old; coal contains carbon 14 showing it is not millions of years old.
And think about it - if an animal dies today it is completely eaten if days if not hours. The fossils we see were clearly buried very quickly. Some have been found giving birth, in the middle of eating another animal, etc.
The fact that fossils exist in vast numbers is testimony to the Global Flood. But of course some people dismiss that idea, not on scientific grounds, but on religious (atheistic) grounds.

Furthermore, even dinosaur fossils have been found containing blood cells - hardly 65 million years old.
http://www.googlesyndicatedsearch.com/u/creationontheweb?q=dino+blood&hl=en&lr=

But check the evidence for yourself - don't by brainwashed by dogmatic evolutionists who don't want us to think for ourselves :)
http://www.creationontheweb.com/content/view/3001

Answer 9

lol at the old earth, young earth explanation. Whatever you do, don't listen to this guy.