Re: Pitman's Miller Time

On 30 Jun, 11:45, Ernest Major <{$t...@xxxxxxxxxxxxxxxxx> wrote:
In message <1183180942.461680.177...@xxxxxxxxxxxxxxxxxxxxxxxxxxxx>,
Seanpit <seanpitnos...@xxxxxxxxxxxxxxxxxxxxxxxxxxx> writes



On Jun 29, 4:25 pm, Ernest Major <{$t...@xxxxxxxxxxxxxxxxx> wrote:

How thick do you think that the chalk beds of southern and eastern
England and the southern North Sea basin are?

As Dr. Pitman doesn't seem to be addressing this point ...

Figures for the total thickness of the Chalk in England include 500m in
the Isle of Wight, 300m at Portsdown, 440m in north Norfolk and 415m on
the Yorkshire coast (rounded from figures in Anderton et al, A Dynamic
Stratigraphy of the British Isles). (Over in Ulster it's only 50m, but
it approaches 900m in the English North Sea.)

Elsewhere I find quoted thicknesses of over 2500m for parts of the
Netherlands North Sea, for a band across northern Denmark (and I think
for the Munster Basin in Germany as well), but these figures include
redeposited chalk from adjacent shallower areas.

Where do you think your hypothetical algal blooms got all that Calcium
Carbonate from? (When we talk of the Chalk Sea we don't mean that the
sea was composed of chalk, rather than water.)

So lets take 1000m as an estimate of the amount of thickness of Chalk to
be explained.

Calcium Carbonate is about 0.1% by mass of sea water. Chalk is about 2.5
times as dense as water. (Less dense than much other Calcium Carbonate.)
So to produce 1000m of chalk we need to extract the Calcium Carbonate
from a column of water 2.5 million meters deep, that's 2500 kilometers
(Noah's flood was a minnow by comparison), or produce the Chalk
sufficiently slowly that the Calcium Carbonate in the photic zone (40m)
can be replenished.

Sure, if you were to assume present day concentrations of calcium
carbonate. If one assumes a balanced steady-state model, it does
appear that at present the slow input of calcium carbonate into the
oceans from rivers, etc., may be a major limiting factor in carbonate
skeletal production and preservation in the ocean. The question here
though is what would happen to all of these numbers during and after a
huge worldwide catastrophe that includes massive floods, huge
volcanoes, large-scale organic decay, and warm oceans/seas?

<McEnroe>
You CAN NOT be serious.
</McEnroe>

You can only increase the Calcium Carbonate concentration of sea water
by so much; water does not have an infinite capacity for the dissolution
of Calcium Carbonate. Perhaps you can cut the depth of the water column
required to 1000 km, rather than 2500 km, but you're postulating a water
column that's more chalk than water.


It's worth noting that the biological activity which converts the
calcium carbonate in sea water into the shells of the microorganisms
which make up the chalk can only occur in the photic zone, which is
the few meters of sea closest to the surface. It's rather limiting -
after all, if there is a greater concentration of living organisms
they cut out the light and *reduce* the depth of the photic zone. So
it doesn't matter if the water column is 1000km or 10 meters deep, the
rate of calcium conversion is the same.

RF

Later on in your reply you attempt to claim the purity of the chalk as
evidence for catastrophic deposition (I've managed to stop laughing).
But here you're proposing processes that are inimical to the deposition
of pure carbonate deposits. Where has all the terrigenous sediment,
volcanic ash, and carbonaceous material gone?



Looking at it from the other direction, extracting all the Calcium
Carbonate of the photic zone produces 16mm of Chalk. Even if you were to
grant -ignoring the question of where the replacement Calcium Carbonate
comes from - one 100% efficient bloom every month, this would take 5,000
years to produce the Chalk. (Geological dating of the Chalk spans 35
million years, but the greater bulk was deposited during the Upper
Chalk, which covers of the order of 10 million years.)

Again, you are assuming present day concentrations of calcium
carbonate. Such uniformitarian thinking isn't remotely likely given
massive shortly-spaced catastrophes that characterize the geologic
record.

Passing over the description of the geological record as characterised
by massive shortly-spaced catastrophes, which is pure assertion,
contradicted by observation ... see above.





Under the right conditions significant increases in the concentration
of marine microorganisms can occur as in plankton "blooms" and red
tides. For instance, a microscopic bioluminescent protozoa in Oyster
Bay, Jamaica is known to increase from 100,000 per liter to 10 million
per liter of ocean water during bloom periods (Seliger et al. 1970).
The reasons for these blooms are poorly understood but suggestions
include turbulence of the sea, wind (Pingree et al. 1977), decaying
fish (Wilson and Collier 1955), nutrients from fresh water inflows and
upwelling, and temperature (Ballantine and Abbott 1957). Some of these
conditions would be generated during a catastrophe such as a worldwide
flood and could favor rapid production of carbonate skeletons by
foraminifera and coccolithophores. The pollution from large duck
ranches on the borders of Moriches Bay, New York is thought to
contribute to a peak concentration of phytoplankton of more than 10
billion organisms per liter.

All that is basically a red-herring. (One hopes, since you feel
qualified that to pontificate on the subject, that you're aware that
mainstream opinion is that plankton productivity in the Chalk Sea was
unusually high.) Why are quoting figures on number of organisms rather
than on carbonate production?



There is also the question of purity. Many of the Cretaceous chalk
deposits you mention are extremely pure - i.e., very little silt and/
or clay contamination. If truly representative of tens of millions of
years, how is such purity explained? Today, under non-catastrophic
non-bloom conditions, such purity of calcium carbonate deposition is
very hard to come by. Rather, a thick layer of very pure chalk is
much more consistent with very rapid, even catastrophic, formation.

Have you considered a holiday in the Bahamas?



How to you explain the change in the bottom fauna over the
stratigraphic column? (I'll assume that you'll explain away the change
to the open water fauna as ecological zonation in the water column.)

With regard to foraminiferal forms? - by various means to include
echophenotypic variation.

http://www.detectingdesign.com/fossilrecord.html#Foraminifers

How about macrofauna?





Alias Ernest Major

Sean Pitman
www.DetectingDesign.com

Note: References provided by Ariel Roth and others

P.S. There is also the interesting problem of total ocean
sedimentation. Until about the 1950s scientists estimated that the
average thickness of ocean sedimentary layers was upward of 22 km
(Petterson 1954). It was assumed that hundreds of millions of years
of sediment transported by rivers to the oceans would add up
significantly. Around the 1950s these estimates were reduced to 2-3
km. By the mid-1970s seismic data forced a further reduction for
major portions of the ocean floor to around 0.1 km with an overall
average of only 0.4 km (~1 km in a very small region near the
continental margins).
Now isn't that interesting? Given the amount of sediment
currently transported by the Earth's rivers into the oceans, all the
oceans should have been completely filled several times over by now.
Oh, I know, subduction via plate tectonics is supposed to explain this
little problem. However, estimates of the input of sediments into the
ocean by rivers, coastal erosion, wind, etc., average around 30
billion tons per year. Yet, the estimated amount of sediment removed
by subduction per year is only 2.5 billion tons per year. That means
that the present volume of sediment on the ocean floor and continental
margins (~4e17 tons) could be deposited at current rates in less than
15 million years.
You see, your position isn't without its little mysteries . . .

I see that you'll adopt uniformitarianism, even cardboard-cutout
uniformitarianism, when it suits your purposes.

In the absence of citations I can't check your figures, but it looks as
is you're comparing apples and oranges - by neglecting sediment
deposition on the continental shelves, which is where most of eroded
material ends up.

Also there are reasons to believe that current erosion rate is enhanced
by anthropogenic effects, and is raised above the long term average.
--
alias Ernest Major


.

Relevant Pages

  • Re: Pitmans Miller Time
    ... >England and the southern North Sea basin are? ... redeposited chalk from adjacent shallower areas. ... Calcium Carbonate is about 0.1% by mass of sea water. ...
    (talk.origins)
  • Re: Pitmans Miller Time
    ... England and the southern North Sea basin are? ... redeposited chalk from adjacent shallower areas. ... times as dense as water. ... (Less dense than much other Calcium Carbonate.) ...
    (talk.origins)
  • Re: Pitmans Miller Time
    ... The resulting algal blooms could easily have ... produced very thick chalk layers in very short order. ... How thick do you think that the chalk beds of southern and eastern England and the southern North Sea basin are? ... (I'll assume that you'll explain away the change to the open water fauna as ecological zonation in the water column.) ...
    (talk.origins)
  • Re: Pitmans Miller Time
    ... England and the southern North Sea basin are? ... redeposited chalk from adjacent shallower areas. ... Calcium Carbonate is about 0.1% by mass of sea water. ... per liter of ocean water during bloom periods. ...
    (talk.origins)
  • Re: Pitmans Miller Time
    ... The formation of the chalk layers in the ... |>England and the southern North Sea basin are? ... assume sufficient light levels the entire depth of the water column) ... | So to produce 1000m of chalk we need to extract the Calcium Carbonate ...
    (talk.origins)