Dead animals would surely decay and disappear if buried at such a slow rate. That gives an average of about 9 inches every 1000 years. Geologists claim this is an undisturbed bed that has accumulated over a period of 16 million years. In the Bighorn Basin of Wyoming and Montana in the United States, a 10,000 foot thick bed of sediments contains many land animal fossils. These facts agree with the suggestion that rivers have been flowing into the oceans only since the major flood that covered the earth a few thousand years ago. Other rivers such as the Nile River of Egypt or the Po River of Italy have deltas that could have developed in only a few thousand years. Since the Mississippi Delta now fills in only a small part of the Gulf of Mexico, it is obvious that the river has not been flowing into the gulf for many millions of years. Other smaller rivers that also drain into the Gulf of Mexico would shorten that time. What would happen if this process went on for millions of years? In the case of the Mississippi River (Figure 1), calculations indicate that its delta would have filled the Gulf of Mexico in ten million years. This is a fan-shaped projection of land that builds out farther and farther into the ocean. If this happens for hundreds and thousands of years, a delta is built up where the river enters the ocean. When the river water reaches the ocean, it slows down and drops its sediment to the ocean floor. 2) River deltasĪs suggested above, water in rivers moves a lot of dirt and ground-up rock (sediment) down to the sea. Mountains still stand tall and land exists well above sea level. If that were true, erosion would have washed all the land into the oceans several times over. Science textbooks may tell us that more than 500 million years have passed since living organisms became abundant in the earth.
In the mountains erosion would be much faster. If we use 5000 years as the time needed to remove one foot from the surface of the earth, it would take a little more than 25 million years to cut the land down one mile.
Geologists have calculated that it takes on the average several thousand years to erode one foot. Glaciers will break away rocks and carry them along. Running water such as streams and rivers (even rain drops) slowly wear (erode) down the mountains. When we look at the mountains we may think that they never change. Listed below are some evidences seen in rocks and fossils that tell us the earth is not very old.
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