From: Steven M Smith (smsmith@usgs.gov)
Date: Mon Nov 17 2003 - 12:12:14 EST
Bill Payne writes:
>On Fri, 14 Nov 2003 08:37:16 -0700 "Steven M Smith" <smsmith@usgs.gov>
>writes:
>> Interesting connection of ideas! Until Glenn showed that JPG graph
>> of oil generation
>> <http://home.entouch.net/dmd/OilGenerationRichardFowlerPETEX2000.jpg
>> had never thought about oil generation being episodic. This
>> observation suggests that conditions were different during those
>> periods.
> Careful, Steve, you're starting to sound like Kent Hovind. :-)
Bill,
It is a good thing you included a smiley face with that sentence. I've met
Kent in person and have no desire to be compared with him. I guess I
don't see how my words about episodic oil generation sound anything like
the stuff Hovind sells. I can only surmise that you are referring to idea
that conditions can be different in the past then they are today. But this
is hardly an extremist YEC view. Geologists readily admit that there have
been conditions on the earth that are different than those today. There
have been several different times - Late Precambrian 'snowball earth',
Pangaea or other supercontinents, global warming during the Cretaceous,
oxidation of the oceans near the end of the Archean, glacial maximums
during the Pleistocene - to name just a very few. The strawman of
gradualistic Substantive Uniformitarianism geology that Hovind likes to
bash has been dead for over 50 years. (Substantive Uniformitarianism - a
testable and discredited theory of geologic change postulating uniformity
of rates or material conditions as defined by Gould, 1965, Am. Jour. Sci.,
v. 263, p.223-8). Unfortunately, it takes a long time to change public
perception, which is what Hovind exploits. I cringe every time I hear
someone say that a geologic feature eroded "one sand grain at a time."
In a parallel reply to Glenn Morton, Bill writes:
> I saw on some YEC video that oil is forming today in the Gulf of
> California. They showed underwater a drop of oil as it escaped from
> the bottom and floated up in the water. The message was that oil is
> not difficult at all to form under the right conditions. We may not
> know what those conditions were, but we do know that oil formed
> somehow, regardless of our ignorance as to the process. Understanding
> the process isn't important in this context. The question is how do
> we generate the organics for the process to convert to oil.
I'll have to disagree with your conclusion. Understanding the process _is_
important and the question is _much more_ than just generating "the
organics for the process to convert to oil." You may have noticed that my
response and Glenn's response to your original iron-in-the-ocean post were
very different. I would argue that this is because we were looking at
different parts of the process. I am more familiar with metallic ore
deposits than petroleum so I am going to use a gold deposit to illustrate
my point and then apply it to petroleum. There are several 'steps'
necessary to create a gold deposit. First, you need a source of gold.
This gold is often very diffuse in the source rock and would never be
economically recoverable. Second, you need a mechanism to mobilize,
concentrate, and transport the gold. Circulating saline hydrothermal
waters are one such mechanism. Third, you need a mechanism to deposit the
gold in economic quantities. For example, boiling the water as pressure
decreases in near surface cracks to form gold-bearing quartz veins. In
Economic Geology, we often summarized these process steps as 'Source,
Transport, & Deposition.' If any step fails, then you don't get an
economic deposit and exploration companies move on.
Petroleum appears to have a couple of additional steps. 1) Source of
organic material; 2) Preservation of organic material; 3) Cooking or
maturation of the organic material to form oil; 4) Transportation of the
oil; and 5) Deposition or trapping of the oil in a suitable structure that
allows for concentration to economic quantities. Miss a step and you won't
get an oil field for Glenn to discover with his geophysical tools. (This
is a simplified list of process steps and I realize that under different
economic conditions, petroleum companies have explored and occasionally
tapped resources that have 'missed a step' by physically adding processes -
such as with oil shales.)
In our replies to your original post, I focused on Process Step 1 (more
organic sources) and Glenn looked at Process Step 2 (conditions for
preserving the organics). Both processes are important in understanding
the 8 oil-generation episodes. As for your oil drop comment ... without
understanding the processes, that YEC video of a drop of oil escaping from
the bottom of the Gulf of California, is irrelevant. It does not address
the process issues nor does it address geologic time issues - the usual
reason stuff like this is shown in YEC videos.
Steve
[Disclaimer: The opinions expressed herein are my own and are not to be
attributed to my employer.]
_____________
Steven M. Smith, Geologist, U.S. Geological Survey
Box 25046, M.S. 973, DFC, Denver, CO 80225
Office: (303)236-1192, Fax: (303)236-3200
Email: smsmith@usgs.gov
-USGS Nat'l Geochem. Database NURE HSSR Web Site-
http://pubs.usgs.gov/of/1997/ofr-97-0492/
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