Noah and descendants

Noah as we saw, in my previous post was the only person who himself and his family made it through from the pre-flood era.
Noah was 600 years old when the floods came upon the earth. Shem, Noah 's son was approximately 100 years old during the flood.
Now it is surprising to note that Abraham was a contemporary of Noah.
We can observe from the portion succeeding the flood that.
1.Abraham was a contemporary of Noah and that Noah dies when Abraham was 60 years.
2.Assuming that Abraham met Noah he must have got a first hand information about the life in the pre-flood times, even perhaps information about moments before the fall, passed on from Seth[Adam's son].
If we take the geneology of generations from Noah to Abraham,we can discover that
Shem, Arphaxad, Shelah and Eber all outlived their descendants : Peleg,Reu and Serug.
Abraham never saw his grandfather Nahor but still may have seen Noah, Shem, Arphaxad, Shelah and Eber his ancestors.
We see a sharp fall in life span with each generation from Noah till Abraham. With an even depressed life span in the times of Peleg, Reu and Serug probably due to the separation of continents during Peleg's time.
A rise in life span is seen from Nahor.
More about Abraham's kindred and family in the next post.
Good day.