Assumptions Distort Geological Dating

In a major geology journal, geologists admit that
their dating schemes rest on questionable assumptions

 

 

In a rare show of candor, geologists in the prestigious American Geophysical Union (AGU) admit that unproveable assumptions often dictate how rock strata are dated. Their statements are Open Access in the journal Geophysical Research Letters, so everyone is free to see what they confess, which includes implications that assumptions of uniformity can lead to gross inaccuracies in dating rocks, especially if non-uniform processes are not taken into account.

None of what follows should be construed to suggest that the authors (Barefoot, Nittrouer, and Straub) doubt the Geological Column with its millions of years. Their concern is accuracy when interpolating deposition rates within formations. For those outside the consensus Deep Time paradigm, however, some principles of interpretation they describe could be expanded for questioning even more assumptions.

Sedimentary Processes and the Temporal Resolution of Sedimentary Strata (Geophysical Research Letters, 6 July 2023). The Plain Language Summary of this research letter indicates that uniformitarianism is still often used to interpret rocks. Uniformitarianism stems from Charles Lyell’s doctrine in the 19th century that “the present is the key to the past”—i.e., present rates should be used to infer past rates. This principle was also fundamental to Charles Darwin’s thinking about the rate of evolutionary change in biology: the effect of the slow accumulation of small changes over time.

Sedimentary rocks can be used to measure the amount of time that passed between events in Earth history. Since it is rare to find layers of rock whose age can be measured, one needs a simplifying assumption: the thickness of sedimentary rocks is proportional to the amount of time that passed. In other words, the sediment accumulated relatively steadily, and gaps are short relative to the duration of interest. In this study, we show that this approach incorrectly dates events in the timeline, and erroneously inflates time durations. The bias is most significant when a change in environmental conditions causes sediment to spread more widely across the landscape than it did before. The bias is not as pronounced when sediment deposits are localized. Clues and context from sedimentary rocks may help reveal whether sediment was spreading widely or locally in the past. Using this evidence, geologists will be able to identify sections where simplifying assumptions will not hold, and can apply appropriate corrections.

In this summary, they have said that the “simplifying assumption” of uniformitarianism (steady deposition) can bias interpretation, and does so most significantly when sediments are widespread. It should be noted at this point that many of the layers in the Grand Canyon are widespread across the continental United States, and some of the “megasequences” of rock strata continue onto other continents.

Here are the “Key Points” of this paper:

• If sediment dispersal changes through time and time is interpolated from long-term rates, one will misestimate durations from strata
• Misestimation is not inevitable in the strata. Some changes in sediment dispersal result in distortion, while others do not
• Geologic clues that indicate the degree of sediment localization are key to diagnosing stratigraphic sections with substantial distortion

As stated, they believe there are ways to identify and correct distorted interpretations. If the sediments are localized, they believe, they are less likely to show distortions in deposition rates. But is that always true?

This question is important, because “Sedimentary rocks are the main geologic archive used to reconstruct paleoclimate, tectonic motions, and the history of life on Earth,” they say. And yet inferring the passage of time is not straightforward, and in fact is error-prone when wrong assumptions are made.

The most commonly-used age models assume relatively steady, continuous sedimentation to interpolate linearly between marker beds of known age. That is, gaps should be short compared to the interval of interest, and distributed uniformly in the stratigraphic column. When these assumptions do not hold, establishing a timeline from sedimentary strata is not straightforward.

Some assumptions “do not hold” and yet they maintain confidence about “marker beds of known age.” What assumptions went into the dating of those beds? This matters more than they might be willing to consider. “Issues of timing and duration are central to interpreting many consequential events in Earth’s history,” they say. Knowing one’s assumptions is therefore critical to assessing the credibility of one’s conclusions.

Time Inflation

The authors already stated that the assumption of uniformitarianism “erroneously inflates time durations.” Time dilation is not just a function of relativity in cosmology, therefore; time dilation can be a function of assumptions in geology! Some rock strata can be younger than they look to a uniformitarian geologist.

One thing that can grossly distort the time duration of a sequence is a break in deposition: a discontinuity, or unconformity.

We use the term “unconformity” throughout to refer to gaps in the stratigraphic record of any duration, due to any cause. Allogenic [“caused elsewhere”] changes in environmental boundary conditions (e.g., sea level, tectonic uplift) that erode or starve basins of sediment leave unconformities in the stratigraphic column. Within a geologic basin, emergent internal (i.e., autogenic) [“caused locally”] sediment transport dynamics focus erosion and deposition in some portions of the basin while other regions receive no sediment at all (Davies & Shillito, 2021; Ganti et al., 2011; Straub & Foreman, 2018; Straub et al., 2009). As a result, for a given stratigraphic column, geologic time does not advance up section linearly. Instead, periods of inactivity and erosion are interspersed with bursts of sediment accumulation (Paola et al., 2018; Schumer et al., 2011; Tipper, 2015).

The present is not the key to the past, therefore. They have discounted uniformitarianism, at least as it applies to a sequence under study by a geologist. The researcher assuming constant deposition cannot call that assumption reliable. How often does this occur in the field?

Layers of known age are uncommon, which makes it challenging to calibrate age models to account for sections of missing time in sedimentary strata. In the absence of other information, the default approach is to interpolate linearly between layers of known age, which inherently assumes that the sediment accumulation rate between them is steady and constant (Abels et al., 2010; Jarochowska et al., 2020; Westerhold et al., 2009; Wilf et al., 2003).

The phrase “sections of missing time” brings to mind our diagram of Grand Canyon, where secular geologists claim at least four major discontinuities lasting millions of years each. Consider this diagram as we continue through the AGU paper:

The authors go on to discuss how most geologists assume that discontinuities (unconformities) are long-lived and rare. But then they appear to say this is justified.

Because we lack the ability to directly measure the amount of unrecorded time in a stratigraphic column, assumptions like steady, continuous sedimentation will remain a practical means for estimating the timing and tempo of past climate, tectonics, and biological evolution. However, it is essential (a) to quantify how these assumptions impact our reconstructions of geologic time, and (b) to investigate how their influence can be mitigated.

Ideal vs Real

The bulk of the paper discusses experiments they performed to come up with models for assessing time dilation in sediments. They flooded a basin with sediments at different velocities, observing the extent of deposition over the area. But do these “idealized” experiments translate well to vast depositions in actual formations on earth?

In all our experiments (positive, negative, and control), we observed that linear time interpolation generated apparent time dilation when the event of interest was short relative to the compensation timescale….  The dependence on apparent event duration on the true duration is a consequence of the Sadler effect (Sadler & Strauss, 1990), where the apparent accumulation rate increases as shorter time windows are measured. That is, we expect this dilation and compression simply because the stratigraphic column is incomplete, with many undetectable hiatuses.

Would this not indicate that a short, huge catastrophic event would generate even more time dilation? A geologist might assume that a large deposit (e.g., some of the vast beds exposed in the Grand Canyon) took millions of years, when in reality it could have been formed rapidly.

There are differences between the control experiment and the experiments where we manipulated flood amplitude. Apparent time dilation in positive transitions (flood intensification) exceeded time dilation in the control experiment (>90% probability for all treatment levels, Figure 3). In other words, during time intervals when floods intensified, the resulting sediment package was thicker on average than a similar time interval when conditions did not change. If a linear age model were applied to reconstruct the duration of positive flood transition events, it would overestimate the true elapsed time by as much as 30%. This effect is above and beyond what would be expected due to the Sadler effect alone.

Obviously they could not test a catastrophic flood model with vast quantities of sediment dumped over a surface in a short time. If they had, perhaps the overestimate would be much larger than 30%.

Our experiments demonstrated that temporary changes in sediment deposition patterns can alter the completeness of the resulting stratigraphic column. By assuming linear time accumulation between dated horizons under these circumstances, geologic events appear to start too early in the stratigraphic column, and unfold over a longer interval of time than they did in reality. The apparent time dilation effect is especially pronounced when the event is abrupt relative to the autogenic dynamics of the sedimentary system.

Those are exactly the conditions that the global flood described in Genesis would entail: an abrupt onset followed by a short but heavy deposition of sediments. The time dilation under such conditions could be extreme. A geologist might think it started millions of years ago and lasted a long time when, in reality, it was a catastrophic, wide-ranging event.

Time Dilation

The authors discuss a few episodes from the deep-time consensus that could be “substantially time dilated.” These include the PETM (Paleocene-Eocene Thermal Maximum, assumed to be 55 million years ago) and the CIE (Shuram carbon isotope excursion at ca. 570 million years ago). They admit, though, that the dates of these events are “very challenging to constrain.” They do not discuss the Grand Canyon, the Channeled Scablands, or other sites of rapid catastrophic conditions.

The effects we have described here almost certainly lurk in the sedimentary records of other depositional environments, where biological and geochemical proxies are used to establish the chronology of major events in Earth history. The suite of sedimentological and geological context clues that might indicate time distortion will vary across sedimentary basins and depositional environments. Nonetheless, our experiments suggest a way forward in these circumstances: one should try to distinguish between episodes where sediment deposition is focused in small areas or spread widely across the depositional system.

The general rule is that time dilation is real. Some of the causes they found for time dilation may not be the only ones.

Our experiments suggest a general rule: environmental change that shifts sediment deposition patterns from localized to widespread deposition is likely to distort the preservation of geologic time. However, this need not be the only, or even the most important way that shifting sedimentary processes affect the temporal resolution of stratigraphy. Importantly, there are also feedbacks and interactions between sediment deposition patterns and the biogeochemical markers that stratigraphers use to reconstruct paleoenvironmental histories. It will remain a challenge to untangle multiple different effects from a common cause (Holland, 2016; Peters, 2005, 2006). For example, a change in sea level (Davies et al., 2009) may coincide with the last occurrence of a fossil in the strata, and sea level rise itself also affects sediment localization.

The authors end by boasting that their experiments provide a “framework” for interpreting conditions that might lead to time dilation in strata. But realistically, experiments performed in a confined space cannot replicate conditions of global extent. This warning must be taken seriously by anyone who looks at the vast extent of sediments on earth and tries to understand how they came about. Deep time should not be assumed.

Flood geologists, take note! These secular authors do not question Deep Time, but they have exposed assumptions that underlie the consensus belief in millions and billions of years. There is no reason scientifically or empirically to conclude Deep Time if unique conditions in a global catastrophe were responsible for sediments and fossils as we observe them.

The Genesis Flood involved rapid onset, heavy sediment loads, oscillations in speed and intensity throughout the flood year, rises and drops in sea level, and “billions of dead things buried in rock layers laid down by water all over the earth” as Ken Ham quips. Additional factors include, but are not limited to, (1) drastic folds in rock layers indicating the sediments were soft and unconsolidated when distorted, (2) fault lines that proceed all the way up through formations but are not truncated at the gaps, (3) flat contacts where old-earth geologists assume gaps of many millions of years transpired, suggesting immediate deposition of the next formation, (4) large boulders above the Great Unconformity transported long distances, (5) fossil graveyards showing mixtures of marine and terrestrial organisms jumbled together, without bioturbation, (6) vast extent of deposits covering continents, and (7) megasequences of similar formations found around the world.

These and many other evidences of a global catastrophe are discussed annually by flood geologists with PhDs. If it were not for the censorship of their ideas by Big Science and Big Media, their evidences would be given due consideration. It will not be taken seriously until Darwinian evolution falls, because Darwin needs those precious billions of years in which to hide his magical thinking.

Recommended Resource: Terry Mortenson’s book The Great Turning Point recounts the history of geology in the late 18th and early 19th centuries, exposing the point when the uniformitarians took over geology to “rid science of Moses.” Mortenson gives biographies of reputable  flood geologists who incorporated the global flood into their interpretations of the fossil and rock records. Charles Lyell’s cabal succeeded in taking over the field of geology in academia and shunning the flood geologists, paving the way for Darwin’s view of the accumulation of slow and gradual changes leading to molecules-to-man evolution. It would take well over a century for neo-catastrophism to arise and question uniformitarian assumptions. Even neo-catastrophism, though, has not been enough to dislodge the deep time paradigm with its obligate parasite, Darwinian evolution.