Copyright 2001 by G. R. Morton. This may be freely distributed so long as no monetary charge is made or alterations made to the text. (home.entouch.net/dmd/seismic.htm)
Few young-earth creationists have ever seen seismic data and considered the problems that it presents for their position. Before I will give links to oil industry seismic data and explain why they indicate lots of time. A seismic line is nothing more than a sonogram of the earth. Just like doctors who use sound to examine babies in utero, we in the oil business use seismic to see what lies below our feet by reflecting sound off the various rock layers. This data is then processed to create a picture of the earth's structure. We then interpret these pictures to tell where oil and gas are.
The data seen by those of us in the oil business clearly contradicts the young-earth interpretations of geology taught by innumerable ‘ministries’. But before I can demonstrate that, I need to explain some of the basics of geology. When sediment laden water covers an area which has an isolated topographically high area, the amount of sediment deposited on top of that high is less than the amount of sediment deposited in the low. The picture below illustrates the fact that sediment is deposited from above and thus preferentially fills the low. Indeed, generally only the tiniest sedimentary particles, shale, end up on the highs. The coarser sediment particles, cobbles, sand etc, end up in the topographic lows.
With faulting, one use the above principle to tell when a fault moved in relation to the time when the sediment was deposited. In the picture below, Fault A didn't move during deposition because the sediment thicknesses are the same across the fault but Fault B did move because the sediments are much thicker on the downthrown side of the fault.
One final feature which we need to take note of. When shale, or mud, is deposited, it has a large volume of water enclosed in it. As the water escapes, the shale will compact into a thinner layer than it was when it was first deposited. This is a difference with sand. Sand does compact, but not nearly by as much. Thus if one deposits a sand next to a shale, filling up the land to a level, as compaction occurs, the area filled by the shale will become a topographic low.
With these three rules we can look at geologic features to show that the sediments took more time to be deposited than young-earth creationists want to admit. We will also look at depositional features, like channels, which also require time to be deposited. Channels must have time to erode into the surface and to meander across the surface. It is important to note that channels require a stable surface for at least a while. In the global flood, which must deposit up to 30,000 feet of sediment within a year, the depositional rate approaches 100 feet per day or 3 feet per hour. Such a situation would mean that there would be no surfaces upon which a channel can meander. In a global flood with such depositional rates of 3 feet per hour and water flow of 3 miles per hour before the water can flow a mile, three feet of sediment would have filled up the area. Even at the fastest velocity observed for water traveling on land, 20 mph, the channel couldn't go very far before the global sedimentation would obstruct it.
The data I am showing here are pictures of seismic I have taken at trade shows. The quality is not the greatest, because I am a lousy photographer and I often have to take the photo at an angle to avoid flashbulb reflection. But the photos are clear enough to see the structures of which I speak. The young-earth creationists claim that overthrusts don't exist. Below are two examples.
The red line above marks the overthrust fault and the green and dark purple line marks two geologic layers which have been thrust on top of themselves. The fact that the beds above and below the overthrust are parallel with other beds either above or below respectively, shows that the area was deposited on a flat layer and that the thrusting occurred after the deposition of the uppermost bed seen under the NW on the seismic. The claim by some creationists that these items don't exist is simply silly.
The overthrust example above is even more complex than the simple overthrust above. In this example the black lines represent the thrust faults. Below the lowest most thrust, the beds are basically horizontal and undeformed. But above that level, the world looks like a train-wreck. Three oil wells are represented by the 2 vertical red lines and the vertical light blue line. Once again, this is not a depositional feature. The layers were deposited and then smashed together after they had had time to become lithified.
Channels meandering through the middle of the sedimentary column also show that it is impossible for the geologic column to be deposited in a one year period. There is no way a channel can form when the sediments are being dropped on top of the channel at a rate of 100 feet per day. The arrows point to 3 different places along the channel. The channel is the wiggly linear object on the seismic.
One interesting form of geophysics is the detail of the gravity field, which can show impact craters which are buried beneath the sediment. This is an example of such a case. Circular features like this, which has no present surface expression, show that meteors fell during the period of time in which the sediments were deposited. If the sediments are due to a global flood, then lots of meteors fell during the flood and it would take only a few of them to kill off all living beings, including Noah. Below is the gravity data showing a 6 km diameter feature.:
The rest of the seismic data I will show is not on this web site, but is being served to from the site at which the picture resides. Thus, I do not have a copy on my web page. I do this to avoid copyright issues as it is very difficult to get permission to show seismic data for a purpose like this. I would suggest opening 2 explorer windows and load the real seismic in one window, read what I say about it and then go look at it after having seen the cartoon of what is on the seismic data.
The first example comes from Wood. It can be found at (searchanddiscovery.com/documents/wood/images/fig05.jpg) and the picture is served from there.
Look at the upper part of the figure as it is the seismic line and locate the area between the two uppermost wiggly lines as shown below in simplified cartoon form.
What we can do with this seismic line is to time the movements of the faults. To the right of fault A (point G on the seismic section) we see the green layer is parallel (in the seismic only the lower wiggly line is shown, which is parallel with time zero which is the land surface.) This area was deposited on a flat surface. On the downthrown side of fault A, we see that the layer thickens which shows that it was lower than the area right of A when it was deposited. The thinning towards fault C (point H on the seismic section) shows that the area around C was relatively higher than the area just next to A. The rapid thickening across fault B only on the bottom of the layer shows that B last moved during the deposition of this layer but the fact that the upper surface of the layer is not cut by fault B shows that the fault has never moved again. Once again, downthrown to C the layer thickens and thins towards D (point H1 on the seismic section) showing that the area down thrown to C was a topographic low at the time of deposition. But, downthrown to D it is also thin and it thickens towards E and the salt. This shows that the area around fault D was formerly (and still is) a high area.
What caused all this motion? The movement of salt. There used to be a continuous layer of salt underlying this area but as sediment was laid down on top of it, it was squeezed out. The weight of the sediment caused it to move. One can see the salt bodies get thicker to the right of the picture and that is because the salt was squeezed that way. As it was squeezed out, it created highs and lows, which influenced the deposition of the sediment above it and the weight of sediment filling the lows further influenced the movement of the salt.
So how do we know that this couldn't have happened in a single year of Noah's flood? Because the viscosity of salt is too high. Viscosity is a measure of how rapidly a fluid can move. Salt is a solid over short times, but over longer periods of time and under a great weight, it will flow. As a comparison, water has a viscosity of .01 poise, thick motor oil has a viscosity of around 10 poise, ice has a viscosity of 1013 poise and salt has a viscosity of 1018 poise. On a glacier made of ice, it takes a year before one can really sea the flowage taking place. Salt is 10,000 times more viscous than ice. It simply won't move rapidly enough to have created the topographic highs and lows we see in the sediments during a one year period. This data is inconsistent with young-earth interpretations of earth history.
Channels
Downcutting channels require time to form. They erode into the sediment. We see these things all the time in the geologic column. The sequence of events is as follows. The sediment is laid down horizontally, and then a channel comes and erodes into the sediment. Below is an example (Abbott). It can be found at: (searchanddiscovery.com/documents/geophysical/Abbott/images/fig08.jpg) and the picture is served from there.
What I did was place a blue line on each of the peaks of the seismic section, so this diagram transfers the information from the seismic. One can see that the thicknesses and pattern of reflections on both sides of the channel (green marks the boundary) are the same. As we have pointed out, constant thickness layers means that the layers were deposited on a flat surface. Now, in the middle of the channel one can see that the reflectors sag a bit and thicken into the center of the channel. This is because the channel was a topographic low when those infilling sediments were deposited. Thus the center of the channel will have slightly thicker sediments than the edges. The sag in all the reflectors is due to the compaction of the shales. Shale is deposited initially as a very non-compact filling, being as much as 80% porous. As the shales lose this porosity, they compact and where they were thickest, they compact the most. Thus, in the process of compacting, they create another topographic low which will be infilled with thicker sediments. In turn, if they are shaley, they too will compact more in the channel center making another topographic low. (a technical note, the structure underneath the channel is merely an illusion as this is a time section and the velocity of sound in the channel is faster than in the horizontal layers, thus creating an illusory structure.)
Thus, the sequence of events is;
1. Deposition of the horizontal layers
2. Erosion by the channel cutting out part of the horizontal layers, making a big hole.
3. then comes the infilling, which requires time because of the compaction must take place with each layer to account for the sag in the center of the channel.
Below we have a case of a pre-existing topography (channels hills etc) covered by horizontal deposition. The parallel nature of the sediments above the canyon show that the entire land sank without tilting. This example is from Abbott and can be found at (searchanddiscovery.com/documents/geophysical/Abbott/images/fig07.jpg) and the image is served from there.
Within the three canyons one can see distorted sedimentary reflections. This means that there was some compaction (as in the channel above) in the initial sediments which infilled the canyons. The bottom of Canyon 1 moved a slight bit AFTER the deposition of the dark blue layer which covers the top of all three canyons. We know this because it has dropped down in relation the the red canyon lip to the left. At point A and B we see erosional terraces and hills which were all covered by the time of the first dark blue layer.
How do we know this took more time than allowed by Noah's flood? First, in canyon 2 we see the light blue layers thickening into the canyon, so we know that the canyon was a topographic low and that there was probably some depositional compaction. But on the left side of canyon 2 the sediments appear to be eroded off before being covered by the dark blue layer. This would require the deposition of the light blue layers and then a time of erosion, which is different from the erosion and faulting which caused the red topography. Thus the sequences is as follows: first the red topography was eroded and faulted into the basement layer. Then after the light blue sediments were laid down, we have erosion of the surface and then covering by the first layer followed by slight fault motion in canyon 1. Given the supposed rates of sedimentation during the flood (up to 100 feet per day), there would be no time for compaction, erosion, and faulting as we see it in this seismic section. If the sediments were laid down rapidly, we should see a sag over each canyon in the sediments above. We don't.
Another example from Abbott which can be found at (searchanddiscovery.com/documents/geophysical/Abbott/images/fig14.jpg)
Below we have an example of an erosional unconformity in which the deeper reflectors which dip to the left were laid down, tilted, then eroded and then covered by the sediment above it. The relatively parallel nature of the sediments (green lines) below the unconformity (red line) show that they were deposited flat. The interesting thing about this is the relatively slow rise of the ocean over the pre-existing hill. The blue horizon marks a time when the sea was no higher than the dark blue line on the left side of the hill. We know this because the sediments thin onto the pre-existing topography (red). They thin to the point of zero, just like happens at the sea's edge today. Only by the pinkish colored horizon does the ocean actually rise enough to cover the hill in its entirety. One can see the pink to blue interval thin over the hill. This unconformity is at least 8000 feet under today's surface which is why I marked the 2.2 and 2.5 second marks. It takes sound waves that long to travel down to the unconformity and then back up to the geophones. After this, the nature of the deposition was relatively parallel and undisturbed, meaning that there was no global upheaval or severe tectonic forces affecting this area. This surely is not consistent with the flood.
Below is a thrust fault which has an oil well drilled through it proving its existence (Cooper et al,.) It can be found at (searchanddiscovery.com/documents/cooper/images/fg06.jpg)
The well encountered the Ordovician Table Point formation and then entered the Cambrian Petit Jardin formation at the pink horizon. The lilac color is the basement rocks which were drilled until the red fault was reached. At that point the well encountered younger Ordovician rocks, and then drilled a normal Ordorvician section, through the Louder (green, back into the Table Point formation (blue), and then into the Petit Jardin (pink). What has happened is that the Cambrian-Ordovician section was deposited on a level basement surface, and after the deposition, the thrusting forced the right side to over-ride the left side of the area. Of course Young-earth creationists claim that such things don't exist. Henry Morris says:
“So we have done what we could, trying to concentrate our research efforts wherever the potential impact in terms of Christian witness would be greatest in relation to expenditures. To a large extent, this criterion has led us to focus on geological field studies, especially on so-called overthrust formations and on anomalous fossils. If it can be shown, by studies at the thrust planes, that enough of these ‘thrust faults’ are not really overthrusts but only normal sedimentary sequences, or if it can be shown that several supposed out-of place fossils have not really been displaced at all but have been normally deposited with the encasing sediments, then the standard geologic age system would eventually have to be abandoned in favor of the creation/flood model of earth history.” Henry M. Morris, A History of Modern Creationism, (San Diego: Master Book Publishers, 1984), p. 251.
And Wysong, without showing any data, says: “Evolutionists begin with the assumption that evolution is true, and from there they gather data and assemble charts to fit this preconception. Facts counter to the geologic column are considered in error, explained through geologic mechanisms like faulting or thrusting, whether or not there is supporting physical evidence, or simply shelved as quirks of nature.” Randy L.Wysong, The Creation-Evolution Controversy (Midland, MI: Inquiry Press, 1976), p. 392. Yet here is a thrust.
Other sites containing interesting seismic features on the net are
(petris.com/bulletns/2001/10oct/1771/images/fg6.htm)
(petris.com/bulletns/2001/10oct/1771/images/fg2.htm)
References
- Abbott, Ward, “Revisiting the Grand Canyon — Through the Eyes of Seismic Sequence Stratigraphy” http://www.searchanddiscovery.com/documents/geophysical/Abbott/index.htm
- Cooper, Mark and John Weissenberger, Ian Knight, Doug Hostad, Derek Gillespie, Henry Williams, Elliott Burden, Janet Porter-Chaudhry, Don Rae,Elizabeth Clark, “Basin Evolution in Western Newfoundland: New Insights from Hydrocarbon Exploration” http://www.searchanddiscovery.com/documents/cooper/index.htm
- Ngah, Kalid, “Structural Framework of Southeastern Malay Basin,” http://www.searchanddiscovery.com/documents/khalid02/index.htm
- Wood, L. J., “Tectonostratigraphic Framework of the Columbus Basin, Eastern Offshore Trinidad” http://www.searchanddiscovery.com/documents/wood/index.htm
Modified 11/25/01
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