Actually, the definitive study of the genealogies in Genesis was done way back in 1890. You should check it out: Primeval Chronology by W.H. Green. A few of the highlights:
THE question of the possible reconciliation of the results
of scientific inquiry respecting the antiquity of man and
the age of the world with the Scripture chronology has
been long and earnestly debated. On the one hand, sci-
entists, deeming them irreconcilable, have been led to
distrust the divine authority of the Scriptures; and, on
the other hand, believers in the divine word have been
led to look upon the investigations of science with an un-
friendly eye, as though they were antagonistic to religious
faith. In my reply to Bishop Colenso in 1863, I had occa-
sion to examine the method and structure of the biblical
genealogies, and incidentally ventured the remark1 that
herein lay the solution of the whole matter. I said:
“There is an element of uncertainty in a computation of
time which rests upon genealogies, as the sacred chronol-
ogy so largely does. Who is to certify us that the ante-
diluvian and ante-Abrahamic genealogies have not been
condensed in the same manner as the post-Abrahamic?
. . . . Our current chronology is based upon the prima
facie impression of these genealogies. But if these
recently discovered indications of the antiquity of man,
over which scientific circles are now so excited, shall,
when carefully inspected and thoroughly weighed, demon-
strate all that any have imagined they might demonstrate,
what then? They will simply show that the popular
chronology is based upon a wrong interpretation, and that,
a select and partial register of ante-Abrahamic names has
been mistaken for a complete one.”
It can scarcely be necessary to adduce proof to one who
has even a superficial acquaintance with the genealogies of
the Bible, that these are frequently abbreviated by the
omission of unimportant names. In fact, abridgment is the
general rule…
In 1 Chronicles 26:24 we read in a list of
appointments made by King David (see 1 Chron. 24:3; 25:1;
26:26), that Shebuel,1 the son of Gershom, the son of Moses,
was ruler of the treasures; and again in 1 Chronicles 23:15, 16,
we find it written, “The sons of Moses were Gershom and
Eliezer. Of the sons of Gershom, Shebuel was the chief.” Now
it is absurd to suppose that the author of Chronicles was so
grossly ignorant as to suppose that the grandson of Moses could
be living in the reign of David, and appointed by him to a
responsible office. Again, in the same connection (1 Chron.
26:31), we read that “among the Hebronites was Jerijah the
chief;” and this Jerijah, or Jeriah (for the names are identical),
was, according to 23:19, the first of the sons of Hebron, and
Hebron was (v. 12) the son of Kohath, the son of Levi (v. 6).
So that if no contraction in the genealogical lists is allowed,
we have the great-grandson of Levi holding a prominent office
in the reign of David.
The genealogy of Ezra is recorded in the book which bears
his name; but we learn from another passage, in which the same
line of descent is given, that it has been abridged by the omission
of six consecutive names…
This disposition to abbreviate genealogies by the omis-
sion of whatever is unessential to the immediate purpose
of the writer is shown by still more remarkable reduc-
tions than those which we have been considering…
The genealogy of Moses and Aaron is thus stated in the
sixth chapter of Exodus: – …
There is abundant proof that this genealogy has been
condensed, as we have already seen that so many others
have been, by the dropping of some of the less important
names.
This is afforded, in the first place, by parallel genealo-
gies of the same period; as that of Bezaleel (I Chron. ii.
18-20), which records seven generations from Jacob; and
that of Joshua (I Chron. vii. 23-27), which records eleven.
Now it is scarcely conceivable that there should be
eleven links in the line of descent from Jacob to Joshua,
and only four from Jacob to Moses.
A still more convincing proof is yielded by Num. iii.
19, 27, 28, from which it appears that the four sons of Ko-
hath severally gave rise to the families of the Amramites,
the Izharites, the Hebronites, and the Uzzielites; and
that the number of the male members of these families of a
month old and upward was 8,600 one year after the Ex-
odus. So that, if no abridgment has taken place in the
genealogy, the grandfather of Moses had, in the lifetime
of the latter, 8,600 descendants of the male sex alone,
2,750 of them being between the ages of thirty and fifty
(Num. iv. 36)…
But do not the chronological statements introduced
into these genealogies oblige us to regard them as neces-
sarily continuous? Why should the author be so partic-
ular to state, in every case, with unfailing regularity, the
age of each patriarch at the birth of his son, unless it
was his design thus to construct a chronology of this
entire period, and to afford his readers the necessary ele-
ments for a computation of the interval from the creation
to the deluge and from the deluge to Abraham? And if
this was his design, he must of course have aimed to make
his list complete. The omission of even a single name
would create an error.
But are we really justified in supposing that the author
of these genealogies entertained such a purpose? It is a
noticeable fact that he never puts them to such a use him-
1890.] Primeval Chronology. 297
self. He nowhere sums these numbers, nor suggests
their summation. No chronological statement is deduced
from these genealogies, either by him or by any inspired
writer. There is no computation anywhere in Scripture
of the time that elapsed from the creation or from the
deluge, as there is from the descent into Egypt to the
Exodus (Ex. xii. 40), or from the Exodus to the building
of the temple (I Kings vi. 1). And if the numbers in these
genealogies are for the sake of constructing a chronology,
why are numbers introduced which have no possible rela-
tion to such a purpose? Why are we told how long each
patriarch lived after the birth of his son, and what was
the entire length of his life?..
For the answers to those questions, read the article. It is amazing that a conservative Biblical scholar, simply comparing Scripture to Scripture, could convincingly refute the idea that the genealogies of Genesis are useful for calculating the age of the Earth – and do it in 1890 – but we are still talking about it.