Why do some rocks contian fossils ?

Question

and which one does

Answer 1

Because when an organism dies, they sometimes rot in a soft substance, such as lava or mud. Their skeleton outline is preserved and shows us the shape and anatomy of the creature.

Answer 2

sedimentry rocks do.

it's because sedimentry rocks are formed by grains of sand etc being comressed together over millions of years. Animals die du to the circumstances, if they're in the ocean (etc, places with which make it hard for the body to decay - tar pits, deserts, ice though they're technically not fossils...more mummys) they sink to the bottom and become compressed with the layers and become imbedded in the stone which is formed from all the particles joining together, then we find them.

Answer 3

Sedimentary rocks are generally the only ones that bear fossils. What happens is that creatures die, and get deposited with the sediments that create sedimentary rocks. Igneous rocks cannot bear fossils. They are formed from lava or magma, so if the rock once held a fossil, it would have melted. Metamorphosed rocks likewise do not usually hold fossils because the heat and pressure needed to form a metamorphic rock will destroy the fossil.

Answer 4

Satan puts them there to try to make people not believe in evolution.

Heh.

Answer 5

omg all rocks do not contain fossils!! Only sedimentary do. You may sometimes get 'ghost structures' in rocks that have not been metamorphosed much but that's about it.

The most common process is organisms that live in the sea will die and become buried under layers of sediments over time. The pressure under the sea causes the minerals in the fossils to be replaced with others. The rocks undergo lithification and a fossil is created.

Graptolites are found in shales and so can many other fossils, but i have only ever seen graptolites in a shale. Things such as coral, trees, brachiopods, bivalves etc. are found in rocks such as limestone and other sedimentary rocks.

Answer 6

Various explanations have been put forth throughout history to explain what fossils are and how they came to be where they were found. Many of these explanations relied on folktales or mythologies. In China the fossil bones of ancient mammals including Homo erectus were often mistaken for “dragon bones” and used as medicine and aphrodisiacs. In the West the presence of fossilized sea creatures high up on mountainsides was seen as proof of the biblical deluge. More scientific views of fossils began to emerge during the Renaissance. For example, Leonardo Da Vinci noticed discrepancies with the use of the biblical flood narrative as an explanation for fossil origins:

        "If the Deluge had carried the shells for distances of three and four hundred miles from the sea it would have carried them mixed with various other natural objects all heaped up together; but even at such distances from the sea we see the oysters all together and also the shellfish and the cuttlefish and all the other shells which congregate together, found all together dead; and the solitary shells are found apart from one another as we see them every day on the sea-shores.

        And we find oysters together in very large families, among which some may be seen with their shells still joined together, indicating that they were left there by the sea and that they were still living when the strait of Gibraltar was cut through. In the mountains of Parma and Piacenza multitudes of shells and corals with holes may be seen still sticking to the rocks..."

Answer 7

dead animals bones lay in mud or river or stream sediment which in time is covered by more layers of mud or sediments and over time the organic parts of the animals bones are replaced by minerals, and in modern times anthropologist have found bones uncovered by ether rain or excavation and they see the bones in the rocks which once was the bones of animals.

Answer 8

at one time they were at the bottom of a sea or ocean. later. due to tectonic plate movement they were uplifted or the sea went dry.

Answer 9

It depends on the enviornment in which it is in. All rocks  can have fossils though.