Controversies Related to the Cretaceous-Tertiary Extinction Provide
No Comfort to Young-Earth Creationists
Kevin R. Henke, Ph.D.
10 November 2004
The following material may be freely copied and distributed as long as the author is acknowledged and the text is not altered, edited or sold.
An asteroid or large meteorite struck the Yucatan Peninsula of Mexico about 65.0 million years ago and produced the Chicxulub crater. A popular hypothesis states that this impact was responsible for the Cretaceous-Tertiary (K-T) mass extinction. An interesting science article by Keller et al. (2004) now challenges the validity of this hypothesis. Not surprisingly, in an essay at the "Answers" in Genesis (AiG) website, young-Earth creationist (YEC) and medical doctor Carl Wieland misuses this article in an attempt to disparage geology and promote the mythical "Genesis Flood".
Citing sedimentological, biostratigraphic (using foraminifera), magnetostratigraphic, stable isotope and iridium measurements, Keller et al. (2004) argue that the K-T extinction occurred about 300,000 years after the Chicxulub impact. In other words, the impact was not directly responsible for the extinction. Keller et al. (2004, p. 3757-3758) further argue that Chicxulub was probably one of many impacts around 65 million years ago and that the accumulative effects of these multiple impacts, as well as massive volcanism and other factors, could have been responsible for the mass extinction.
Keller et al. (2004) investigated a sediment core (Yax-1), which was collected at approximately 60 kilometers from the center of the Chicxulub crater. The core contains a breccia, which was produced from the impact. The K-T boundary is located in a limestone with a green glauconitic clay layer about 50 centimeters above the top of the breccia (Keller et al., 2004, p. 3754). Keller et al. (2004, p. 3753) considered the possibility that the sediments between the breccia and the K-T boundary were immediately deposited as backwash and crater infill after the impact. Of course, YECs must support this fast deposition scenario if they're going to believe that all of the core materials were "Flood" deposits. However, Keller et al. (2004, p. 3755) reject the fast deposition hypothesis by persuasively arguing in the following statements that the sediments between the breccia and the K-T boundary were deposited SLOWLY over about 300,000 years:
Backwash and crater infill requires high-energy currents to erode and transport material, including diverse clasts and faunal elements from the impact breccia and the underlying lithologies and their shallow-water benthic foraminifera. NO EVIDENCE for such reworking exists in the critical 50 cm between the breccia unit and the K-T boundary, NOR DOES SEDIMENTARY EVIDENCE EXIST FOR A HIGH-ENERGY DEPOSITIONAL ENVIRONMENT.... [my emphasis]
Planktic foraminiferal assemblages within the 50-cm interval are of high diversity with small and large, thin- and thick-shelled species, and all are characteristic of the latest Maastrichtian [Late Cretaceous] zone CF1 age. Such uniform assemblages, and the ABSENCE of older reworked species, CANNOT be explained by backwash and crater infill, but they are CONSISTENT with in situ deposition in a LOW-ENERGY hemipelagic environment. [my emphasis]
The presence of burrows below the K-T boundary and in the four glauconitic layers within the 50-cm interval below indicates that DEPOSITION OCCURRED IN A NORMAL SEDIMENTARY ENVIRONMENT with burrowing organisms on the ocean floor. IF THESE DEPOSITS CONSISTED OF HIGH-ENERGY BACKWASH AND CURRENT REWORKING, BURROWS COULD NOT HAVE BEEN PRESERVED. [my emphasis]
The existence of low-energy depositional conditions and animal burrows in the sediments of the 50-cm interval is completely incompatible with Wieland's "Genesis Flood". Like most YECs, Wieland only provides a cursory review of this article and avoids mentioning any of the above statements because they undermine his YEC agenda, including the absurd claim that nothing in the entire Universe is more than 6,000 to 10,000 years old.
Because modern technologies allow geologists to distinguish between events that occurred 65.0 million and 64.7 million years ago, Keller et al. (2004) now believe that the Chicxulub crater can be eliminated as the primary cause of the extinction and that a new search for other candidate craters should be initiated. Considering the effects of erosion and that the surface of the Earth from the Cretaceous to the present has mostly been hidden with water, any alternative crater to Chicxulub may never be found. On the other hand, Keller et al. (2004) have only demonstrated that numerous Cretaceous foraminifera survived the Chicxulub impact. Contrary to Wieland's misconceptions, Keller et al. (2004) NEVER present any arguments or evidence about the timing of dinosaur, ammonoid, plesiosaur, or other K-T extinctions during the deposition of the sediments in their core sample. It's certainly possible that the Chicxulub impact did force the dinosaurs and larger marine organisms into extinction, but spared the foraminifera and other marine microorganisms. Individuals must realize that mass extinctions may occur over several hundred thousand or even a few million years. Furthermore, extinctions may have multiple and complex causes. Indeed, from a geological perspective, we could classify the entire Holocene (the past 10,000 years) as one mass extinction event resulting from thousands of years of human overhunting and climatic changes associated with the end of the last glaciation.
In his essay, Wieland tries to belittle the impact hypothesis and other scientific investigations of the K-T extinction. While groundlessly trusting anything that he sees in his Bible, Wieland views legitimate geological research on the K-T extinction with utter contempt. In reality, geologists developed the impact hypothesis because of valid field and laboratory investigations rather than from any religious devotion to ancient myths or a dedication to atheism. Simultaneously, other scientists recognized that some of the same field and laboratory evidence could also support extensive volcanism as a cause of the K-T extinction. Under the rules of the Method of the Multiple Working Hypotheses (for discussions, see: "Science, Unlike YEC Dogma Corrects Itself" in Ancient Ice Ages AND Submarine Landslides, but NOT Noah's Flood), impacts, massive volcanism, and all other natural hypotheses should be equally judged on their merits and no attempt should be made to find "The Truth" by devoting oneself to a ruling hypothesis. In contrast, YECs are chained to dictatorial religious doctrines and they offer no credible scientific explanations for mass extinctions. Their "Flood geology" was thoroughly debunked more than 150 years ago (Young, 1982) and shows no sign of being resurrected.
Unlike legitimate scientists, YECs often blatantly distort and selectively ignore field data, laboratory results and the scientific literature (as Wieland does) to protect their religious dogmas. If problems arise with their religious agenda, YECs are more than willing to invoke groundless miracles to further protect their beliefs from failure. Of course, this magical, biased and imaginary approach to explaining nature has no place in reality or science. No one wants a forensic scientist to tell a court that "demons" committed the crime or a physicist that simply "explains" the existence of lightning as "God did it!" Likewise, miracles should not be invoked to explain the origin of a volcanic rock, whether it formed yesterday or three billion years ago.
While celebrating the supposed demise of the Chicxulub crater as the "smoking gun" for the K-T extinction, Wieland correctly recognizes that if the Keller et al. (2004) study survives scrutiny, scientists will respond to the results as examples of the self-correcting nature of science. YECs, like all dogmatists, rejoice in the "certainty" of their beliefs and scoff when science isn't able to provide similar "Truths" and "Final Answers". Certainly, science is not in the business of comforting people with "security blankets". That is, science is a discipline for mature adults that must be willing to use multiple working hypotheses and deal with the possibility that hypotheses may thrive for 20 years and then suddenly die. Although technological advances and further research continue to improve the reliability of scientific investigations, science never guarantees that a definitive solution will always be found. This is true whether the investigation involves solving an unwitnessed crime, studying a complex chemical reaction, or developing methods to predict the next week's weather. In contrast to the slow and steady progress of science, YECs and other dogmatists have immersed themselves in a childish, superstitious and shrinking world-view that is based on "god-of-the-gaps".
Keller, G., T. Adatte, W. Stinnesbeck, M. Rebolledo-Vieyra, J. U. Fucugauchi, U. Kramar, and D. Stueben, 2004, "Chicxulub Impact Predates the K-T Boundary Mass Extinction", Proc. Nat. Acad. Sci. USA, v. 101, n. 11, March 16, p. 3753-3758.
Young, D.A., 1982, Christianity and the Age of the Earth, Zondervan Publishing House, Grand Rapids, MI 49506.