The Story the Earth Tells
The earth tells us that the sum total of its rock strata was laid down over vast periods of time. Many individual rock bodies obviously formed rapidly. For example, a fossilized ripple mark or delicate organism must have been buried relatively gently and quickly. However, the formation of the geologic column as a whole was obviously a prolonged process. The accompanying illustrations perhaps help us understand these concepts.
There is proof upon proof of an ancient earth. A compelling example is the evidence of prolonged activity of sediment-sifting organisms. Worms, various shelled animals and other organisms disturb and extract food from sediment on the sea floor. It is not uncommon to encounter thousands of meters thickness of sedimentary rock which has been completely disturbed in this way. Traces of such activity may be visible to the naked eye and will certainly be visible with the assistance of a hand lens. How long do you estimate it would take to sift, disturb and eat sediment over an area of, say, 10,000 square kilometers, ultimately accumulating to a thickness of, say, 1,000 meters?............... This link explores dating of past events.
Some of the fine detail of these diagrams should be regarded as approximate. We have a reliable overall picture of the history of life, as revealed in the earth, but new discoveries will always necessitate changes in the minor details.