Bioturbation and
Other Anomalies

by Laurence D Smart B.Sc.Agr., Dip.Ed., Grad.Dip.Ed



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Evolutionists analyse rocks and fossils by interpreting them in light of what happens today. This is the basis of their uniformatarian principle - i.e. sediment is deposited at a constant rate, with little or no incidence of catastrophe. Does an analysis of the sedimentary rocks indicate a uniformatarian, slow, gradual deposition of sediment over billions of years? Let's examine the evidence.



Firstly, how is the rate of sedimentation calculated when no one was there to measure it as it settled? Evolutionary geology states that the layers of sedimentary rocks were laid down very slowly on the bottom of seas and lakes over millions of years. Evolutionists calculate the rate of this sedimentation by dividing the depth of rock layers by the assessed ages of the rocks. For example, the 2100m thick sedimentary layers of the Grand Canyon are said to have been laid down over 300 million years (550 million - 250 million). This is a rate of 7m per million years, or 0.007 mm per year (2100 m 300 my).




Secondly, what does the sediment look like once it has turned into sedimentary rock? Accumulating sediment (even at the slow rate of 0.007 mm/yr) should show evidence of the organisms that lived in the sludge where it settled. This however is not the case. Instead, the boundary between successive layers of sediment are predominantly undisturbed, 'knife-edged', and free of fossils.

Fossils are not found evenly spread throughout sedimentary rocks, defying the uniformatarian principle. They are usually found in patches, in fossil beds and in fossil graveyards. What evidence is there that sedimentary rocks do not form the way evolutions say that they do?


OBSERVATION #1 - "The Absence of Bioturbation"

Sediment laid down under the sea or lake should not form thin, distinct layers. Instead, the activity of burrowing organisms should disturb it, continually mixing the sediment as it settles. This bioturbation would then produce a more uniform sediment that did not show thin, distinct layers.



OBSERVATION #2 - "The Mussel Anomaly"

Rivers, lakes and shallow seas today contain many shellfish (molluscs) in the surface sediment. The common ones are mussels and pipis. Over the years these multiply, and without the harvesting of humans, build up to populations of considerable size. The ones that die, rot and disintegrate, leaving their shell(s) behind. These shells are very resistant to weathering, especially while they are under the sediment, protected from the rasping action of moving water.

What sort of shell remnants should we expect to find in sedimentary rocks formed from lakes and shallow seas? Let's consider the mussel that occurs as freshwater and salt water species. A mussel has a spatial cubic volume of 0.000135m3 (0.03m x 0.10m x 0.045m). For argument sake, let's allocate a longevity of 10 years to each mollusc, and a density of 1/m3 (one live mussel in every cubic metre of sediment). In 1 million years, 100,000 mussels will have lived in each cubic metre of sediment. The dead remnants of these mussels would form a layer 13.5m tall if their two shells stayed joined.



During this time of 1 million years, 7 metres of sediment should have been deposited - according to our earlier calculation. The resultant sediment mixture would produce a layer with a very large number of mussel shells in it. Unless the environment in the past had always been unfavourable to mussels and their evolutionary shellfish ancestors, this is what sedimentary rock from shallow seas, lakes and rivers should look like.

Sedimentary rocks said to have formed from lakes and shallow seas do not contain a good, evenly spread population of these molluscs. Instead, they are either absent, or appear in mass graves.


OBSERVATION #3 - "Missing Soil Layers"

The evolutionary history of the earth claims that the seas rose and sank many times. It is said that the sinking created land bridges for animals to migrate between islands and continents. The rising seas inundated the land, submerging it for millions of years. This is the common explanation for intermittent layers of coal.

Any land that has been submerged under rising seas should still show remnants of its existence above sea level. There should be layers with roots from trees, grasses and herbs, burrows of large and small animals, as well as fossilized trapped soil creatures.

 Layers said to have been part of rising and falling seas show an almost complete absence of these surface soil features.


OBSERVATION #4 - "The Lack of Marine Fossils"

Seas and lakes are teaming with life. Each layer of sediment should be thick with shells, crabs, fish bones, etc. No layer of sediment should be without marine fossils. However, what is generally found in sedimentary rocks are layers, and layers, of fossil-free sediment.


OBSERVATION #5 - "The Mixing Of Land And Marine Fossils"

Fossils form on the surface of the earth in peat bogs, tar pits, glacial deposits, and in wind-blown deposits in deserts. These all trap and produce fossils of land animals. The land surface is then said by evolutionists to sink slowly as the deposits build up, eventually forming sedimentary rock.

All marine sediment should be relatively free of land animal fossils as land animals fossilize on the land surface. Land sediment should not contain marine fossils. However, in many fossil deposits there is a mixture of land and sea animals. Uniformatarian principles cannot explain these mixtures.


OBSERVATION #6 - "Manganese Nodules"

Manganese nodules are black, potato-sized slabs made of iron and manganese that form on the ocean floor. Deep-sea photographs indicate that they cover 20%-50% of the Pacific Ocean floor. These nodules form extremely slowly, but they are found mainly on the surface of the sediment.

If these nodules formed on ocean floors that remained undisturbed for hundreds of millions of years, as evolutionists suggest, they should have been buried long ago. Scientists do not have an explanation of why the nodules are mainly on the sea floor surface.



So, the evidence from sediment outlined in the 6 points above does not fit the slow, evolutionary model. The worldwide data, however, is consistent with sediment laid down rapidly and in huge volumes by a catastrophic global flood.