Fluidization pipes: evidence of large-scale watery catastrophe
by Tas Walker
A few years
ago, some geologists in Australia were objecting in print to the idea of interpreting
geology in terms of the Bible and Noah’s Flood.1 They argued that it was impossible to
explain the rocks of the world within a 6,000-year time-frame, even allowing for
a year-long global flood. For some reason they had not appreciated that the evidences
of large-scale, watery catastrophe in the geological record2
are just what we would expect from the global Flood of the Bible.3
Indeed, one vivid illustration was featured on the cover of the same issue of the
magazine in which their objections were published.4
Photo by David Rawlings
Fluidisation Pipe: Cone shaped sandstone column piercing a thick layer of bedded
sandstone.4
The cover (Figure, left) showed a bedded sandstone formation in a remote part of
Arnhem Land Aboriginal Reserve, Northern Territory, Australia. The sedimentary bedding
varies in thickness from thin to medium, and is sub-horizontal. Altogether the sandstone
pictured, which is quite friable, is over 5 m thick.
This particular outcrop is part of a 340-m-thick
unit called the McKay Sandstone within the mildly-deformed McArthur Basin of northern
Australia. The unit comprises medium- to coarse-grained sandstone together with
minor fine-grained sandstone, granules, pebbles and basalt.5
It has been classified as Paleoproterozoic, based on interpretations of U-Pb dating
of zircons from igneous units in the area.5,6
In the picture, a large, cylindrical structure cuts vertically across the bedding
of the sedimentary rock. The diameter of the columnar structure is not constant,
but varies from 1.3–1.7 m over its length.
Like the surrounding sedimentary rock, the column
is composed of sandstone, but in this case it is unbedded, except for vague vertical
layering, concentric with its circumference. The base of the column sits on top
of a fine-grained basalt sill 3–4 m thick. The top of the sill has a ropy
surface and contacts baked and vuggy7 sandstone and
mudstone, in places brecciated. The sill contains distinctly zoned amygdales8
that are larger in the middle of the sill.
Numerous similar pipes occur within the sandstone, at irregular
intervals along strike,9 at the same level immediately
above the sill. They vary in diameter from 2–10 m and are up to 5 m high.
The longest preserved length is over 4 m.4,5
These columns point to large-scale geological catastrophe. When the basalt lava
intruded horizontally, the sand was still wet and unconsolidated. The heat from
the molten rock boiled the water immediately above the sill. As a result the water
welled up, forming a vertical column through the sandstone. The upward flowing water
suspended the sand particles against gravity, causing the sediment to behave like
a fluid. Naturally, the flow destroyed the layers of horizontal bedding. Because
of this behaviour, the structure has been called a ‘fluidisation pipe’.
It is clear that fluidisation pipes point to large-scale rapid geological processes.
First, the sedimentation rate must have been
extremely rapid to produce an unconsolidated, water-filled layer of sand at least
5 m thick over a large geographic area. There are many other evidences in the McKay
Sandstone that the sedimentation rate was very high, including the occurrence of
planar lamination (even in thick-bedded units),10
metre-scale folding of beds, and large dewatering structures.11
Rather than millions of years, the sedimentation rate indicates very rapid deposition.
The basalt sill also points to large-scale rapid, catastrophe. The complete thickness
of the sill must have intruded quickly over the whole area before the water-logged
sediments were able to quench and harden the magma. A thin sill would have been
easily quenched, and a slow intrusion rate would have allowed time for the water
to start circulating and cool the magma. The entire sill must have been emplaced
very quickly before the overlying water had time to boil and establish the strong
circulation that fluidised the sand.
And finally, the fluidisation pipes mean that sedimentation and sill emplacement
occurred together, indicating that there was virtually no time between the two processes.
Thus, fluidisation pipes are one more example of large-scale, watery catastrophe
in the geological record.
With such clear evidence of pervasive, inter-woven catastrophe, it is surprising
that geologists do not see the implications. Even though they carefully describe
the structures and appreciate something of the speed and scale of the processes,
they do not realise that the evidence destroys the concept of millions of years.
This illustrates how a paradigm can constrain people from seeing the implications
of what they observe. The bigger implication, of course, is that the evidence is
just what we would expect from the global Flood of the Bible.
Biblical geology is such a refreshing, stimulating, alternative. It breaks open
the straight-jacketed thinking of long-age philosophy, and it makes sense of the
evidence.
References
- Blake, P., More geology and the Bible I; Morand, V. and Cayley,
R, More geology and the Bible II, Letters, The Australian Geologist109:5,
1998. The full exchange is reproduced on my
Biblical Geology Website, 29 August, 2000. Return to text.
- Catastrophe is now more widely acknowledged in the geological record.
See for example: Ager, D, The New Catastrophism: The Importance of the Rare Event
in Geological History, Cambridge University Press, 1993. Return to
text.
- Morris, J.D.,
The Young Earth, Creation-Life Publishers, Colorado Springs,
CO, 1994, gives many geological evidences of the global Flood. Return
to text.
- Rawlings, D, Cover photo, The Australian Geologist,
109:4, 1998. Return to text.
- Sweet, I.P. et al., Mount Marumba, Northern Territory,
1:250,000 Geological Map Series Explanatory Notes, SD 53–6, Australian
Geological Survey Organisation, Canberra, 1999. Return to text.
- Scott, D.L. et al., Basement framework and geodynamic
evolution of the Palaeoproterozoic superbasins of north-central Australia: an integrated
review of the geochemical, geochronological and geophysical data, Australian J.
Earth Sciences 47:341–380, 2000. Return to
text.
- A vug is an unfilled cavity in a rock, commonly not joined
to other cavities, and often lined with vapour-phase crystals different from the
mineral composition of the surrounding rock. Return to text.
- An amygdale is a secondary mineral deposit in an elongated,
rounded or almond shaped vesicle in igneous rock, especially basalt. Return
to text.
- The direction in which a horizontal line can be drawn on a bedding
plane. Return to text.
- Sweet et al., Ref. 5, p. 17. Return to
text.
- Sweet et al., Ref. 5, p. 18. Return to
text.
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