The Geologic Column

Encyclopaedia Britannica.  “Geology.”  Encyclopaedia Britannica 10:167–169.  1955.  The encyclopaedia's general article on geology, which Whitcomb and Morris cite from the 1956 printing and attribute to R. H. Rastall, a Cambridge lecturer in economic geology.  Its section on stratigraphy states the circularity objection and answers it in the same paragraph.

1. 1a.

   Page 168:  “It cannot be denied that from a strictly philosophical standpoint geologists are here arguing in a circle. The succession of organisms has been determined by a study of their remains embedded in the rocks, and the relative ages of the rocks are determined by the remains of organisms that they contain. Nevertheless the arguments are perfectly conclusive.”  “It is possible to a very large extent to determine the order of superposition and succession of the strata without any reference at all to their fossils. When the fossils in their turn are correlated with this succession they are found to occur in a certain definite order, and no other. Consequently, when the purely physical evidence of superposition cannot be applied, as for example to the strata of two widely separated regions, it is safe to take the fossils as a guide”. ↩ ↩

Snelling, Andrew A.  Earth's Catastrophic Past: Geology, Creation and the Flood.  Dallas: Institute for Creation Research.  2009.  A two-volume, continuously paginated textbook of Flood geology by a young-earth geologist, later of Answers in Genesis.  Volume 1, chapters 45 to 49 (pp. 299–336), is the most thorough young-earth account of how the column was built and correlated, and it accepts the column's order as fact.  Volume 2, chapter 94, discusses where the Flood ends.

1. 2a.

   Page 300:  “this principle ought to apply regardless of whether the deposition is slow and gradual or extremely rapid as in a global watery cataclysm (e.g., the Genesis Flood).” ↩

2. 2b.

   Page 300:  “Nevertheless, the basic principles embodied in the geologic column are based on observational data that at face value imply relative age relationships between strata, but not necessarily the millions-of-years interpretation imposed on the strata by the uniformitarian assumption.” ↩

3. 2c.

   Page 301:  “Cuvier thought the fossils were the remains of once-living organisms that had been annihilated during the catastrophes. New organisms had been created following each catastrophe”. ↩

4. 2d.

   Page 304:  “Many of these widely-used descriptive rock units did contain fossils, and the recognition of diagnostic fossil aggregates (assemblages) in these mappable rock units was not, in any way, a matter of interpretation dependent upon any uniformitarian or evolutionary assumptions. Strata sequences could be walked and mapped in the field, and so the transition in fossil content of these units was an empirical observation.” ↩

5. 2e.

   Page 304:  “The geological timescale was thus constructed and imposed on the empirically-developed geologic column as an interpretation arising from uniformitarian and evolutionary assumptions.” ↩

6. 2f.

   Page 316:  “It is thus both feasible and possible to use fossils and fossil assemblages for correlation of the rock strata containing them without encumbrance by or commitment to the geological timescale.” ↩

7. 2g.

   Page 329:  “That the standard geologic column is a genuine physical reality and represents a reliable record of the earth's physical history has a number of far-reaching implications. Foremost among these is the implication that just as the order of physical rock units throughout the whole geologic column is real, then so also is the sequence of different fossils and fossil assemblages found in the rock units of which the geologic column is comprised.” ↩ ↩

8. 2h.

   Page 329:  “The sequence of fossils and fossil assemblages is simply an objective empirical observation.” ↩

9. 2i.

   Page 329:  “In fact, the original study and description of the divisions of the geologic column, particularly the Cambrian to Recent strata, were done largely by creationists, who believed that the fossils and fossil assemblages they were describing in the strata sequences were a record of death and destruction that occurred during the Genesis Flood.” ↩

10. 2j.

    Page 761:  “available evidence suggests that the Flood/post-Flood boundary certainly must be above the Cretaceous/Tertiary boundary in the strata record.  This approximately corresponds to a transition from worldwide/continental to regional/local deposition and therefore possibly more correctly marks the transition point to the regression stage of the Flood.”  Page 759:  He rules out a Tertiary/Quaternary boundary on the ground that the Ice Age needs.  “several centuries”. ↩

Clarey, Timothy L., and Davis J. Werner.  “Global stratigraphy and the fossil record validate a Flood origin for the geologic column.”  Proceedings of the Eighth International Conference on Creationism, 327–350.  Pittsburgh: Creation Science Fellowship.  Edited by J. H. Whitmore.  2018.  A paper by two Institute for Creation Research geologists who compiled over 1,500 local stratigraphic columns across North America, South America and Africa and traced six megasequences and distinctive beds such as salt and chert from column to column.  They conclude that the column is valid on a global scale and is the record of the Flood.

1. 3a.

   Page 327, section Abstract:  “Creationists should not be critical of the geologic column, but embrace it as evidence of a global Flood event.”  Page 349:  “Creationists should embrace the geologic column as it is robust evidence of a global Flood.” ↩ ↩ ↩

2. 3b.

   Page 330:  “Oil industry geologists have tracked the megasequence boundaries from the craton to the ocean shelves on the basis of distinctive seismic reflection patterns (many due to abrupt truncations) as well as lithologic changes in oil well bores (using downhole well logs, biostratigraphy data and cores)”. ↩

3. 3c.

   Page 327:  “Sequences are defined as discrete packages of sedimentary rock bounded top and bottom by erosional surfaces, with coarse sandstone layers at the bottom (deposited first) followed by shales and then limestone at the top (deposited last) (Sloss 1963).” ↩

Morris, Henry M., and Gary E. Parker.  What Is Creation Science?  San Diego: Creation-Life Publishers.  1982.  A popular book by the founder of the Institute for Creation Research and the biologist Gary Parker, who wrote the chapter on fossils.  Morris's chapter "The Shaky Foundations of the Geologic Column" is a full statement of the circularity charge, and it carries two concessions:  that fossils do lie in a vertical order, and that the age system was complete before radioactivity was discovered.

1. 4a.

   Page 163:  “Now the geologic column is an idea, not an actual series of rock layers. Nowhere do we find the complete sequence.”  Gary Parker.  He continues:  “But still, the geologic column does represent a tendency for fossils to be found in groups and for those groups to be found in a certain vertical order. Cambrian trilobites and Cretaceous dinosaurs aren't usually found together.” ↩

2. 4b.

   Page 234:  “Many such out-of-order stratigraphic series do give evidence of involvement in intense deformations of the crust, folds and fractures as well as thrust-faulting. On the other hand, there are many of them where there is no evidence of significant movement at all — they are simply out of sequence stratigraphically.” ↩

3. 4c.

   Pages 235–237:  “Not even radioactive minerals which the rock may contain will determine its geologic age, for the whole geologic age system had been completely worked out before the discovery of radioactivity.” ↩ ↩ ↩

4. 4d.

   Page 239:  “If you doubt it, bring in a suite of good index fossils, and the specialist, without asking where or in what order they were collected, will lay them out on the table in chronological order.”  Morris is quoting the paleontologist J. A. Jeletsky (1956).  O'Rourke quotes the same sentence and answers it (pp. 51–52 of his paper). ↩

5. 4e.

   Page 240:  “That is, since evolution takes place worldwide, rocks containing fossils representing a certain stage of evolution are assumed to have been formed during the age when that evolutionary stage was attained.” ↩ ↩ ↩

6. 4f.

   Page 240:  “How can the fossil sequence prove evolution if the rocks containing the fossils have been dated by those fossils on the basis of the assumed stage of evolution of those same fossils? This is pure circular reasoning, based on the arbitrary assumption that the Evolution Model is true.”  “If the Creation Model is a better model than the Evolution Model, as creationists believe, then evolution is not true, and there is no way to distinguish one geologic age from another. In fact, they may all be essentially the same age!” ↩

7. 4g.

   Pages 240–242:  Morris quotes David B. Kitts, "Paleontology and evolutionary theory," Evolution 28 (1974): 458–472, beginning.  “But the danger of circularity is still present.”  and Ronald R. West, "Paleoecology and uniformitarianism," Compass 45 (1968).  Neither paper was obtained for this article, so the wording is Morris's. ↩

Counted for this article from every row of the commission's GSSP table as it stood on 20 October 2026.²⁰ The table has 81 rows for stages from the Cambrian up, 79 ratified and 2 proposed.  Of the 79 ratified, the primary marker is the first appearance of a single fossil species for 53, a last occurrence for 2, a composite or imprecise fossil event for 8, a magnetic polarity reversal for 8, a reversal together with a fossil first appearance for 1 (the Aquitanian), a carbon-isotope excursion for 3, a Holocene climate event for 3, and the iridium anomaly for 1 (the base of the Danian).  Fossil events of some kind are the marker for 63 of the 79.  The chart prints base levels for a few stages that have no row in the table, so the counts describe the table as published. ↩ ↩

Scientific Creationism.  San Diego: Creation-Life Publishers.  Edited by Henry M. Morris.  1974.  The Institute for Creation Research's textbook of creation science, prepared for use in public schools, with Henry Morris as editor.  Its chapters on the geologic column accept the order of the fossils as a prediction of the Flood model and argue that the ages assigned to it are circular.

1. 6a.

   Page 116:  “Creationists do not question the general validity of the geologic column, however, at least as an indicator of the usual order of deposition of the fossils, since this same order fits perfectly the cataclysmic model.” ↩ ↩ ↩

2. 6b.

   Page 136:  “Here is obviously a powerful system of circular reasoning. Fossils are used as the only key for placing rocks in chronological order. The criterion for assigning fossils to specific places in that chronology is the assumed evolutionary progression of life; the assumed evolutionary progression is based on the fossil record so constructed.” ↩

Wise, Kurt P., and Donna Richardson.  “What Biostratigraphic Continuity Suggests about Earth History.”  Proceedings of the Ninth International Conference on Creationism 9:611–625.  2023.  A paper by Kurt Wise, a young-earth paleontologist with a Harvard doctorate, and Donna Richardson.  At each of 114 globally defined stratigraphic boundaries they counted, in the Paleobiology Database, the species found on both sides of the boundary within about two degrees of each other, and used the pattern to place the Flood's start and end.

1. 7a.

   Page 623:  “Concerning biostratigraphy in general, the global biostratigraphic column seems to be real.” ↩ ↩

2. 7b.

   Page 623:  “However, with the possible exception of the Cambrian, there may be no relationship between the litho- and bio-stratigraphic columns. This suggests that the order in which the Flood buried fossils bore no relationship to fluctuations in Flood energy.” ↩ ↩

3. 7c.

   Page 623:  “A Danian/Selandian boundary is suggested by global NLSSS data”.  “More specifically on the position of the pre-Flood/Flood boundary, NLSSS values suggest a boundary somewhere between the Rhyacian/Orosirian boundary and the Cambrian/Ordovician boundary.”  “NLSSS values argue very strongly against a boundary in the upper Cenozoic.” ↩ ↩

Computed for this article from Macrostrat, the University of Wisconsin's public database of regional stratigraphic columns (macrostrat.org, CC-BY), with the script research/column-completeness.ts and its output.  Each of the 1,402 active land columns, together covering 32.1 million km², was scored for which of Woodmorappe's ten periods it holds, Cambrian to Cretaceous plus a Tertiary made of Paleogene or Neogene.  A period counts if a sedimentary, volcanic or metasedimentary unit lies mainly within it or spans most of it;  granites and other intrusions are left out, as Woodmorappe left out "postorogenic granites."  Ten columns hold all ten periods (0.8 % of the area), 1,107 hold five or fewer (79.0 % of columns, 70.3 % of the area), and 55 hold none.  A looser rule, counting any unit whose range touches a period, gives 31 complete columns (2.8 % of the area) and 61.6 % of the area with five or fewer.  The ten complete columns are the Waco uplift of the Ouachita belt in Texas, the Cedar Creek Anticline on the Montana and North Dakota side of the Williston Basin, three in east-central Alaska, the Elko area of Nevada, the Canyon and Pavant Ranges of Utah, the thrust belt and Fossil Basin of Wyoming, Tombstone in Yukon, and central Ellesmere Island.  A Macrostrat column is a regional composite, so it may hold periods that lie side by side within its area rather than stacked in one well. ↩ ↩

Steno, Nicolaus.  The Prodromus of Nicolaus Steno's Dissertation Concerning a Solid Body Enclosed by Process of Nature Within a Solid.  New York: Macmillan.  Translated by John Garrett Winter.  1916.  An English translation of the Danish anatomist's 1669 essay on fossils and strata, written while he worked in Tuscany.  It sets out, as propositions "considered as certain," the rules now called superposition, original horizontality and lateral continuity, and it frames the history of Tuscany inside the biblical Flood.  The article uses it for the first printed statement of the relative-dating rules, by an author who was himself a Flood geologist.

1. 9a.

   Page 230:  “At the time when any given stratum was being formed, all the matter resting upon it was fluid, and, therefore, at the time when the lowest stratum was being formed, none of the upper strata existed.”  Proposition 4 in Steno's list. ↩

2. 9b.

   Page 230:  “Hence it follows that strata either perpendicular to the horizon or inclined toward it, were at one time parallel to the horizon.” ↩

3. 9c.

   Page 230:  “Hence it follows that in whatever place the bared sides of the strata are seen, either a continuation of the same strata must be sought, or another solid substance must be found which kept the matter of the strata from dispersion.”  Proposition 3. ↩

4. 9d.

   Page 209:  “The fourth part describes various conditions in Tuscany not treated by historians and writers upon natural subjects, and sets forth a process of the universal deluge which is not at variance with the laws governing movements of nature.” ↩

5. 9e.

   Page 258:  “But that which is certain, that the formation of many mollusks which we find to-day must be referred to times coincident with the universal deluge, is sufficiently shown by the following argument.” ↩

Hutton, James.  Theory of the Earth, with Proofs and Illustrations.  Volume 1.  Edinburgh: Cadell, Davies and Creech.  1795.  The Edinburgh naturalist's book-length theory of the earth, built on field descriptions.  Its chapters on granite veins and on the contacts at Jedburgh and Siccar Point are the classic statements of the evidence for cross-cutting relations and unconformities.  Page numbers are those of the 1795 edition.  Mirror:  Archive.org

1. 10a.

   Page 318:  “These are veins of granite which have flowed from the contiguous mass into the stratified stone, and leave no doubt with regard to this proposition, that the granite had flowed in form of subterranean lava”. ↩

2. 10b.

   Page 459:  “Here are two objects to be held in view, in making those observations; the original formation or stratification of the schisti, and the posterior operations by which the present state of things has been procured.”  Written of the coast at Siccar Point, where horizontal sandstone rests on the upturned ends of vertical schist (p. 458). ↩

Smith, William.  Strata Identified by Organized Fossils.  London: W. Arding.  1816.  The canal surveyor's illustrated catalogue of the fossils typical of each English stratum, issued after his 1815 geological map of England and Wales.  It states, from his own fieldwork, that each bed can be recognised by the fossils peculiar to it.

1. 11a.

   Page 1:  “The organized Fossils (which might be called the antiquities of Nature,) and their localities also, may be understood by all, even the most illiterate:  for they are so fixed in the earth as not to be mistaken or misplaced; and may be as readily referred to in any part of the course of the Stratum which contains them, as in the cabinets of the curious”. ↩

2. 11b.

   Page 2:  “my attention was first drawn to them, by a previous discovery of regularity in the direction and dip of the various Strata in the hills around Bath; for it was the nice distinction which those similar rocks required, which led me to the discovery of organic remains peculiar to each Stratum.” ↩

Cuvier, Georges.  Essay on the Theory of the Earth.  Edinburgh: William Blackwood.  3rd edition.  Translated by Robert Jameson.  1817.  The French anatomist's argument that the earth's history was broken by sudden revolutions, with Jameson's notes.  Note K summarises the 1811 study of the rocks around Paris by Cuvier and Alexandre Brongniart, which set out the order of the Paris Basin formations and of the mammal bones in them.

1. 12a.

   Page 295:  “The whole series of formations, according to Cuvier and Brongniart, appear to be arranged in the following order, from below upwards”.  Eleven formations follow, from the chalk with flint at the base to the alluvial deposits at the top. ↩

2. 12b.

   Page 109:  “There is also a determinate order observable in the disposition of these bones in regard to each other, which indicates a very remarkable succession in the appearance of the different species.”  Page 110:  The elephants, rhinoceroses, hippopotamuses and mastodons.  “are never found along with the more ancient genera”. ↩

Oppel, Albert.  Die Juraformation Englands, Frankreichs und des südwestlichen Deutschlands.  Stuttgart: Ebner & Seubert.  1856.  The German paleontologist's comparison of the Jurassic of England, France and south-west Germany, issued in parts from 1856 to 1858.  It divides the system into thin zones, each marked by species found in it alone, and traces them from country to country.  It is the origin of the zone as the working unit of biostratigraphy.

1. 13a.

   Page 3, section Vorrede:  “Es wird dabei nöthig gemacht, mit Hintansetzung der mineralogischen Beschaffenheit der Schichten, die verticale Verbreitung jeder einzelnen Species an den verschiedensten Orten zu erforschen, hernach diejenigen Zonen hervorzuheben, welche durch stätes und alleiniges Auftreten gewisser Arten sich von den angrenzenden als bestimmte Horizonte absondern.”  In English:  "It is necessary, setting aside the mineral character of the beds, to investigate the vertical distribution of each single species at the most varied places, and then to pick out those zones that set themselves apart from their neighbours as definite horizons by the constant and exclusive occurrence of certain species."  The next sentences add that this yields an ideal profile whose members are characterised everywhere by the same species, and.  “Eine solche Theilung habe ich versucht und sie bei den meisten Etagen ausführbar gefunden”.  "I have attempted such a division and found it workable for most stages."  Translations are this article's. ↩

A Geologic Time Scale 2004.  Cambridge: Cambridge University Press.  Edited by Felix M. Gradstein, James G. Ogg and Alan G. Smith.  2004.  The reference timescale of the International Commission on Stratigraphy for its period, written by specialists for each period.  Each period chapter opens with the history of the period's name and the markers used to define its stages.  The article uses those histories for who named each period and when, and the introduction for the rules for fixing a stage boundary.

1. 14a.

   Page 43:  “the "Cambrian System" was applied by Sedgwick to non-fossiliferous strata below Murchison's fossil-bearing Silurian (Sedgwick and Murchison, 1835)”.  Page 165:  “the Ordovician was proposed as a new system by Lapworth in 1879.”  Page 188:  “The Silurian System was erected by Murchison (1839)”.  Page 202:  “The Devonian System was established by Sedgwick and Murchison (1839)”.  Page 223:  “Conybeare and Phillips in 1822 constituted these units as the Carboniferous or Medial Order”.  Page 249:  “In 1841, after a tour of Imperial Russia, R. I. Murchison, in collaboration with Russian geologists, named the Permian System”.  Page 271:  “The Trias of Friedrich August von Alberti (1834)”.  Page 307:  “The term "Jura Kalkstein" was applied by Alexander von Humboldt (1799)”.  “Alexander Brongniart (1829) coined the term "Terrains Jurassiques"”.  Page 344:  “The "Terrain Crétacé" was established by d'Omalius d'Halloy (1822)”.  Page 384:  “Naumann (1866) combined in his "Paleogen Stufe," the Eocene and Oligocene, as opposed to the "Neogen Stufe" of Hornes (1853)”.  The same page dates the older terms Tertiary to Arduino (1759) and Quaternary to Desnoyers (1829). ↩

2. 14b.

   Page 202:  “The Devonian System was established by Sedgwick and Murchison (1839) when it was recognized through the then unpublished work of Lonsdale (1840) that marine rocks in southwest England were the equivalent of terrestrial Old Red Sandstone deposits in Wales, the north of England, and Scotland: an early recognition of facies change.” ↩

3. 14c.

   Page 165:  “It was a compromise solution to the controversy over strata in North Wales that had been included by Adam Sedgwick in his Cambrian System but which were also included by Murchison as constituting the lower part of his Silurian System.”  “Lapworth (1879-80) described the stratigraphic distribution of British graptolites at the same time that he proposed the Ordovician System, and graptolites have played a major role in the recognition and correlation of Ordovician rocks since that time.” ↩

4. 14d.

   Page 23:  “"Before formally defining a geochronologic boundary by a GSSP, its practical value — i.e. its correlation potential — has to be thoroughly tested. In this sense, correlation precedes definition" (Remane, 2003).”  “Most primary markers for GSSPs have been biostratigraphic events, but some have utilized other global stratigraphic episodes”. ↩

Wise, Kurt P.  “The Way Geologists Date!”  Proceedings of the First International Conference on Creationism 1:135–138.  Pittsburgh: Creation Science Fellowship.  1986.  A conference paper by a young-earth paleontologist, then a graduate student at Harvard, arguing that creationists are wrong to call geology's three dating methods invalid.  It accepts superposition and biostratigraphy, treats the Lewis Overthrust as a real fault, and says the charge of circular reasoning should be ignored until someone shows a case of it.

1. 15a.

   Page 135:  “Years before Darwin published the Origin of Species, geologists had constructed a geologic column very similar to that used today. As early as the late eighteenth century it began to be recognized that fossils found below others in one area would be found beneath the same ones in another area.” ↩

2. 15b.

   Page 136:  “The existence of an inverted section in a thrust belt region with slickensides, dragfolds, and sheared rubble along the unconformity leaves no reasonable doubt that the Lewis Overthrust is in fact a result of overthrusting. It cannot be considered a contradiction to the geologic column.” ↩

3. 15c.

   Page 136:  “Modern creationist theory predicts that there should be many inverted sections which are not at all associated with faults.”  He adds that until such sections are examined.  “the geologic column must be considered unrefuted, and thus usable in dating rocks”. ↩

4. 15d.

   Page 137:  “A general survey of biostratigraphy should be done to determine if circular reasoning is often used in geology. Until such a time as such a survey is done, accusations of circular reasoning without example are to be ignored. When properly used, biostratigraphy thus remains as a valid method of dating.” ↩

O'Rourke, J. E.  “Pragmatism versus materialism in stratigraphy.”  American Journal of Science 276:47–55.  Jan 1976.  An essay on method by a Pittsburgh stratigrapher.  It tests stratigraphic terms borrowed from physics, finds that some hide assumptions that look circular, and argues that the cure is to present the column first as an observed order of rock features above and below one another, and only then as history.  It is the mainstream paper creationists quote most often on circularity, almost always from its first paragraph.

1. 16a.

   Page 47:  “The intelligent layman has long suspected circular reasoning in the use of rocks to date fossils and fossils to date rocks. The geologist has never bothered to think of a good reply, feeling that explanations are not worth the trouble as long as the work brings results. This is supposed to be hard-headed pragmatism.” ↩

2. 16b.

   Page 47, section Abstract:  “Stratigraphy should present its case first as a cognitive process, from experience; then as a historical process, from inference.” ↩

3. 16c.

   Page 48:  “Index fossils are those known to have a wide horizontal and narrow vertical range and to recur consistently above certain taxa and below others. They are regarded as the features most reliable for accurate, long-distance correlations.” ↩ ↩ ↩

4. 16d.

   Page 52:  “Very well, but the sequence of fossils is primarily a spatial order. The reliability of an index fossil is estimated according to how many times it has been found above one taxon and below another in vertical sections. From a pragmatic standpoint, the method of the specialist amounts to this: on a thousand previous occasions, he has found certain taxa in a certain vertical order; on the 1001st occasion, when the specimens are brought in, the expert arranges them in the customary order.” ↩ ↩

5. 16e.

   Page 52:  “Before it could be used to mark off time units, it had to be calibrated by comparing it to the geologic column, which, as a matter of fact, was put together before evolution was known.”  "It" is evolution, used as a clock. ↩

6. 16f.

   Pages 52–53:  “True, but the dates of debut and extinction of a taxon are known from negative evidence alone, and their accuracy depends on the amount of information available.”  “The dates are determined empirically and are subject to revision.” ↩

7. 16g.

   Page 53:  “The rocks do date the fossils, but the fossils date the rocks more accurately. Stratigraphy cannot avoid this kind of reasoning, if it insists on using only temporal concepts, because circularity is inherent in the derivation of time scales.” ↩

8. 16h.

   Page 54:  “Radiometric dating would not have been feasible if the geologic column had not been erected first.” ↩ ↩

9. 16i.

   Page 55:  “He compares this local sequence to the global column obtained from a great many man-years of work by his predecessors. As long as this cognitive process is acknowledged as the pragmatic basis of stratigraphy, both local and global sections can be treated as chronologies without reproach.” ↩

Murphy, Michael A., and Amos Salvador.  “International Stratigraphic Guide: an abridged version.”  Episodes 22(4):255–271.  1999.  The short form of the rulebook of the International Union of Geological Sciences for naming and defining stratigraphic units, prepared by its subcommission on stratigraphic classification.  Its chapter on biostratigraphy defines biozones by their fossil content and states that fossil correlation is not, by itself, time correlation.

1. 17a.

   Page 261:  “Biostratigraphic units (biozones) are bodies of strata that are defined or characterized on the basis of their contained fossils.” ↩ ↩

2. 17b.

   Page 262:  “Five kinds of biozones are in common use: range zones, interval zones, assemblage zones, abundance zones, and lineage zones. These types of biozones have no hierarchical significance, and are not based on mutually exclusive criteria.” ↩

3. 17c.

   Page 264:  “Biostratigraphic correlation is not necessarily time-correlation. It may approximate time correlation, or it may be the identification of the same biofacies, which may be diachronous.” ↩

North American Commission on Stratigraphic Nomenclature.  “North American Stratigraphic Code.”  Stratigraphy 18(3).  2021.  The rulebook for formally named rock, fossil and time units in North America, revised in 2021.  Articles 48 to 54 govern biostratigraphic units.

1. 18a.

   Page 182, section Article 48, Remark a:  “Biostratigraphic units are distinct from all other kinds of stratigraphic units because their contained fossils record the unidirectional process of organic evolution. As such, the stratigraphic record as a whole contains an unrepeated sequence of fossil taxa that may be used to determine the relative age of their enclosing strata.” ↩ ↩

2. 18b.

   Page 184, section Article 49, Remark d:  “The boundaries of most biostratigraphic units, unlike the boundaries of chronostratigraphic units, are both characteristically and conceptually diachronous.”  “Nevertheless, biostratigraphic units are effective for interpreting chronostratigraphic relations.” ↩

3. 18c.

   Page 185, section Article 54, Remark c:  “Biozones and subbiozones are established empirically and may be modified on the basis of new evidence.” ↩

Karlstrom, Karl E. et al.  “Redefining the Tonto Group of Grand Canyon and recalibrating the Cambrian time scale.”  Geology 48(5):425–430.  2020.  A study of the Cambrian Tonto Group of the Grand Canyon by a team of geologists and trilobite specialists, combining trilobite zones with mineral ages from volcanic grains.  It confirms that the same trilobite zone lies at different levels in the rock formations from west to east.

1. 19a.

   Page 427:  “As noted by McKee and Resser (1945), and confirmed by our work, trilobites of the Glossopleura walcotti Biozone … occur high in the Bright Angel Formation to the west and lower in the east.” ↩

International Commission on Stratigraphy.  GSSP Tables.  2026.  Retrieved Oct 20, 2026.  The commission's own table of every Global Boundary Stratotype Section and Point, giving for each stage the section, the level, the marker events and the ratification status, with the rules for proposing a boundary. ↩

1. 20a.

   Section Rules for chronostratigraphic boundary-definition proposals:  “The boundary MUST be recognized by an observable, unambiguous change in the physical properties or fossil content of the strata, for example the first appearance datum of a fossil species”.  “The markers should be independent of facies”. ↩

2. 20b.

   Section Tournaisian row, Correlation Events:  “Conodont FAD Siphonodella sulcata IMPRECISE (GSSP discovered in 2006 to have biostratigraphic problems, and can not be correlated with precision.)”  The row gives the status as.  “Ratified 1990”. ↩ ↩

Kaiser, Sandra I.  “The Devonian/Carboniferous boundary stratotype section (La Serre, France) revisited.”  Newsletters on Stratigraphy 43(2):195–205.  2009.  A restudy of the conodonts at the section chosen in 1990 to define the base of the Carboniferous.  It finds the defining species earlier than reported, the beds reworked, and the lineage the definition relied on missing, and calls for the boundary to be moved or the section replaced.

1. 21a.

   Page 195, section Abstract:  “New data show that the first occurrence of the index fossil S. sulcata is much earlier than previously reported, which indicates that the base of the Carboniferous has to be fixed at an older stratigraphical level.”  “the evolutionary lineage from S. praesulcata to S. sulcata, which was previously claimed for the definition of the D/C boundary, is obviously absent at La Serre.” ↩ ↩

Corradini, Carlo et al.  “Conodonts across the Devonian/Carboniferous boundary: a review and implication for the redefinition of the boundary and a proposal for an updated conodont zonation.”  Geological Magazine 154(4):888–902.  2016.  A review of conodont ranges across the boundary in several sections by a team from Italy, Poland and the United States, proposing a new zonation and a new defining species.

1. 22a.

   Section Abstract:  “it is suggested that the new criterion for the definition of the base of the Carboniferous system be the First Appearance Datum of Pr. kockeli or Si. bransoni.” ↩

Sadler, Peter M. et al.  “High-resolution geobiologic time-lines: progress and potential, fifty years after the advent of graphic correlation.”  The Sedimentary Record 12(3):4–9.  2014.  A review by the developers of the CONOP program of composite sequences built by computer from many local sections, with a table of published datasets and their sizes.  As the method's authors, they describe its strengths and say where it is weakest, between taxa of different groups or preserved in different rock types.

1. 23a.

   Page 4:  “They routinely contradict one another concerning the sequence of species appearances and disappearances”.  "They" are the local sections, which the authors call witnesses. ↩

2. 23b.

   Page 4:  “Realizing that local range-ends were not correlative, Shaw sought the earliest local first occurrence and youngest local last occurrence for each taxon. He projected information from all sections into the best of them to make a composite reference section.” ↩

3. 23c.

   Page 5, figure 1:  “Key events in a fragment of a composite time-line for 1213 Albian through Maastrichtian ammonite species reported from two or more of 562 globally distributed locations, plus dated ash fall events and stable isotope excursions.”  “constrained by 15,205 local event observations.” ↩ ↩

Sadler, Peter M., and Roger A. Cooper.  “Improved resolution and quantified stratigraphic uncertainty: time scales of the future.”  Newsletters on Stratigraphy 43(1):49–53.  2008.  A short paper presenting a computer-built composite sequence for the Ordovician and Silurian from graptolite ranges.

1. 24a.

   Page 49, section Abstract:  “By using automated procedures for compositing and scaling, we build a time scale for the Ordovician and Silurian from the stratigraphic range-ends of over 1,500 graptolite species from over 214 measured sections worldwide.”  “achieves a resolution that is ten times better than can be achieved by using fossil zones.” ↩

Fan, Jun-xuan et al.  “Data and code for a high-resolution summary of Cambrian to Early Triassic marine invertebrate biodiversity.”  Dryad.  Nov 20, 2019.  The public data record for Fan and colleagues' 2020 paper in Science, which sequenced the ranges of thousands of marine invertebrate species from published Chinese sections with a parallel version of CONOP.  Its abstract gives the size of the dataset before and after filtering.

1. 25a.

   Section Abstract:  “The raw dataset contained 266,110 local Cambrian to Triassic records of 45,318 taxonomic units from 3,766 published stratigraphic sections.”  “The final dataset retained after all standardization procedures included 116,060 local records of the stratigraphic ranges of 11,268 species in 3,112 published stratigraphic sections.”  Species known from one locality only were removed first. ↩

Lu, Zhengbo et al.  “Improving the temporal resolution of middle Eocene–late Oligocene foraminiferal biomagneto-chronology: insights from CONOP and chronologic significance of biotic events.”  Palaeogeography, Palaeoclimatology, Palaeoecology 669:112929.  2025.  An application of CONOP to foraminiferal first and last appearances and magnetic reversals in eleven marine sections and cores.  It is candid about what the method does to the observed ranges and about the uncertainty its search adds.  Mirror:  Escholarship.org

1. 26a.

   Page 4:  “The final dataset contains a total of 480 events (first/last appearances and polarity reversals) of both polarity zones (52) and foraminiferal species (188)”.  Page numbers are those of the open copy. ↩ ↩

2. 26b.

   Page 3:  “We apply Constrained Optimization (CONOP) (Sadler et al., 2009), a quantitative stratigraphic method that preserves all species events by adjusting observed diachronous events to resolve discordance in biostratigraphic correlations.” ↩

3. 26c.

   Page 9:  “Additionally, the nature of the correlation problem in CONOP as an NP problem means that the Simulated Annealing (SA) heuristic algorithm employed by CONOP yields probabilistically optimal solutions, introducing further uncertainty in the order of events”. ↩

Backman, Jan et al.  “Biozonation and biochronology of Miocene through Pleistocene calcareous nannofossils from low and middle latitudes.”  Newsletters on Stratigraphy 45(3):221–244.  2012.  The companion zonation for the Miocene to Pleistocene by the same group, again with a single marker for each boundary and no subzones.

1. 27a.

   Page 221, section Abstract:  “We present 31 biozones using a new code system: CNM1–CNM20; Calcareous Nannofossil Miocene biozones 1 through 20. CNPL1–CNPL11; Calcareous Nannofossil Plio-Pleistocene biozones 1 through 11.”  “A single biohorizon is used for the definition of each biozone boundary.” ↩

Agnini, Claudia et al.  “Biozonation and biochronology of Paleogene calcareous nannofossils from low and middle latitudes.”  Newsletters on Stratigraphy 47(2):131–181.  2014.  A new zonation of the Paleogene by the microscopic plates of marine algae, built from deep-sea drill cores and land sections, with one marker species for each zone boundary.

1. 28a.

   Page 131, section Abstract:  “Thirty-eight new Paleogene biozones are proposed using a new code system: 11 Paleocene biozones (CNP1–CNP11), 21 Eocene biozones (CNE1–CNE21) and 6 Oligocene biozones (CNO1–CNO6).”  “The new scheme uses a limited number of biohorizons, one for each biozone boundary”. ↩

Alnasser, Thamer, and Fahad Badqaish.  “Introduction to biosteering operation.”  AAPG Wiki.  Apr 21, 2022.  An entry by two Saudi Aramco geologists on steering wells by the microfossils in the rock cuttings.  They report over 1,000,000 feet of hole biosteered in the Permian Khuff carbonates over more than thirteen years, with over 90 % reservoir contact, much of it in wells too narrow to carry logging tools, so that the fossils were the main guide.  Mirror:  Archive.org ↩

Whitcomb, John C., and Henry M. Morris.  The Genesis Flood: The Biblical Record and Its Scientific Implications.  Philadelphia: Presbyterian and Reformed.  1961.  The book by a theologian and a hydraulic engineer that launched modern Flood geology.  Its chapter "Modern Geology and the Deluge" argues that the column's correlation rests on evolution and uniformity and that the large overthrusts are fictions.

1. 30a.

   Page 134:  “In turn, the principles of evolution and uniformity are seen to be of paramount importance in the correlation of the geologic strata.”  “The circular reasoning here should be evident and indeed is evident even to many historical geologists.” ↩

2. 30b.

   Page 135:  “It cannot be denied that from a strictly philosophical standpoint geologists are here arguing in a circle. The succession of organisms has been determined by a study of their remains embedded in the rocks, and the relative ages of the rocks are determined by the remains of organisms that they contain.”  The quotation ends here, at the footnote that cites "R. H. Rastall article, 'Geology,' in Encyclopedia Brittannica, 1956, p. 168, Vol. 10." ↩

3. 30c.

   Page 136:  “And when, as frequently occurs, strata are found superposed but with the fossils in the inverse order, this paradox is resolved by saying that the strata must have been inverted through faulting or folding, whether or not there is any physical evidence thereof.” ↩

4. 30d.

   Page 189:  “This does not mean, of course, that belief in the idea of the overthrust itself has been abandoned! This could not be the case unless the standard system of geologic ages also could be rejected.” ↩

5. 30e.

   Page 198:  “Thus, we feel warranted in rejecting the whole concept of overthrusting, at least when applied on the scale of the so-called Lewis and Heart Mountain Thrusts and the many others of similar size and kind, such as the famous Matterhorn (Fig. 20) and Mythen Peaks in the Alps.” ↩ ↩

Morris, Henry M.  “Circular Reasoning in Evolutionary Geology.”  Impact, Institute for Creation Research.  Jun 1, 1977.  A short tract by the Institute's founder, still posted on its website, stating the circularity charge and quoting J. E. O'Rourke and Derek Ager in its support.

1. 31a.

   “That is, the fossil evidence that life has evolved from simple to complex forms over the geological ages depends on the geological ages of the specific rocks in which these fossils are found. The rocks, however, are assigned geologic ages based on the fossil assemblages which they contain. The fossils, in turn, are arranged on the basis of their assumed evolutionary relationships. Thus the main evidence for evolution is based on the assumption of evolution.” ↩ ↩

2. 31b.

   “The geologist has never bothered to think of a good reply, feeling the explanations are not worth the trouble as long as the work brings results.”  O'Rourke's printed text reads "feeling that explanations."  The tract quotes no further. ↩

Woodmorappe, John.  “The geologic column: does it exist?”  CEN Technical Journal 13(2):77–82.  1999.  A reply by the author of the 1981 quantitative study to Glenn Morton's essay "The Entire Geologic Column in North Dakota."  Woodmorappe grants that all ten systems are superposed in some places but argues that by thickness the column is mostly missing and that some systems are assigned by position rather than by their own fossils.

1. 32a.

   Page 77, section Abstract:  “Locally, many of the systems have not been assigned by the index fossils contained in the strata but by indirect methods that take the column for granted — clearly circular reasoning. Thus the geologic column does not exist and so does not need to be explained by Flood geology.” ↩ ↩

2. 32b.

   Page 77:  “Yes, Morris and Parker, whom Morton attacks, are not strictly accurate when they say there is no place on earth where all ten geologic systems are superposed.”  Page 79:  “the Williston Basin in the western USA”. ↩ ↩

3. 32c.

   Page 80:  “I had taken the three-dimensionality of the strata into account by tacitly accepting, as a given, the superposition of lithologies ascribed to different geologic periods. That is, when I considered a map of Ordovician strata and one with Cambrian strata, I assumed that, where the two systems occur in the same geographic locality, Ordovician strata always overlie Cambrian strata (and never the reverse).” ↩

Woodmorappe, John.  “The Geologic Column: Does it exist?”  Creation Ministries International.  Sep 23, 2010.  The web version of the 1999 paper, with added passages.

1. 33a.

   “Clearly, if the periods in these locations were assigned by assuming that the geological column was real, then it is circular reasoning to use the assigned ten periods to argue the reality of the column.” ↩

Oard, Michael J.  “Is the geological column a global sequence?”  Journal of Creation 24(1):56–64.  2010.  A paper by a retired meteorologist with a master's degree in atmospheric science who writes widely on Flood geology, adapted from his chapter in the Creation Research Society's 2006 book on the column.  He grants that the column's broad order holds in the vertical sections of the western United States and argues that its finer divisions are unreliable.

1. 34a.

   Page 56:  “Yes, "catastrophists" generally developed the column, but these catastrophists believed in multiple catastrophes in which the Genesis Flood was just the last and accounted for only the surficial "diluvium".” ↩

2. 34b.

   Page 56:  “Fossil succession over long periods of time was the guiding principle, which essentially is the same as evolution.” ↩

3. 34c.

   Page 57:  “Radiometric dates must agree with the geological column, or the radiometric dates are assumed wrong (or reinterpreted) for various reasons. As a result of this circular reasoning, there are countless problems in radiometric dating.” ↩

4. 34d.

   Page 63:  “As far as the broad arrangement of fossils is concerned, the geological column seems to be generally consistent where observed in vertical sections in the western United States. This gives some confidence that the general order can be applied elsewhere in the world. But when we get into the fine detail of the geological column such as the divisions of the eras, there is much reason for skepticism, especially where the environment of the fossils is similar.” ↩

Reed, John K.  “Toppling the Timescale, Part I: Evaluating the Terrain.”  Creation Research Society Quarterly 44:174–178.  2008.  The first of four papers by a young-earth geologist arguing that creationists should separate the observed rock record from the conceptual column and timescale, and should reject the latter.

1. 35a.

   Page 174, section Abstract:  “The geologic timescale has stood as a fortress of uniformitarian natural history for nearly two centuries. It is an intellectual idol that must be overthrown in order to reassert biblical authority in the realm of natural history.” ↩

Walker, Tas.  “Post-Flood boundary — a robust analysis flawed by hidden assumptions.”  Journal of Creation 28(2):60–61.  2014.  A letter by a Creation Ministries International geologist answering Marcus Ross's 2012 test of a late Flood boundary.  Walker argues that the column and the fossil database built on it carry too many uniformitarian assumptions to locate the boundary.

1. 36a.

   Page 60:  “However, it is incorrect to try to find the post-Flood boundary using the geological column in this way. The problem is that the column is not a physical reality, but a hypothetical construct.” ↩

Matthews, John D.  “The stratigraphic geological column — a dead end.”  Journal of Creation 25(1):98–103.  2011.  A paper by a young-earth writer arguing that the column, built in a naturalistic framework, should be abandoned for a biblical classification of the rocks.

1. 37a.

   Page 98, section Abstract:  “However, even biblical creationists have come to varying conclusions on its truthfulness and utility for historical geology, ranging from acceptance (excluding uniformitarian timescales) to full rejection.” ↩

Eldredge, Niles.  Time Frames: The Rethinking of Darwinian Evolution and the Theory of Punctuated Equilibria.  New York: Simon and Schuster.  1985.  A book by the American Museum of Natural History paleontologist who co-founded the theory of punctuated equilibria, explaining how the theory arose from fossil trilobites.

1. 38a.

   Page 52:  “Long before radioactivity was known to physicists, paleontologists had another way to tell time. Fossils occur in the same vertical sequence throughout the geologic column.”  “if we date the rocks by their fossils, how can we then turn around and talk about patterns of evolutionary change through time in the fossil record?” ↩

Ager, Derek V.  The Nature of the Stratigraphical Record.  Wiley.  1981.  A short, much-quoted book by the British geologist Derek Ager on the gaps and oddities of the stratigraphic record, written to provoke.

1. 39a.

   Page 68:  “It is a problem not easily solved by the classic methods of stratigraphical palaeontology, as obviously we will land ourselves immediately in an impossible circular argument if we say, firstly that a particular lithology is synchronous on the evidence of its fossils, and secondly that the fossils are synchronous on the evidence of the lithology.” ↩

2. 39b.

   Page 69:  “This is what may be called 'event stratigraphy' in which we correlate not the rocks themselves, on their intrinsic petrological characters, nor the fossils, but the events such as the Triassic transgressions”.  “'event stratigraphy' is more accurate, in a chronological sense, than either lithostratigraphy (in the usual sense) or biostratigraphy.” ↩

Oard, Michael J.  “More expansion of fossil time ranges.”  Journal of Creation 33(3):3–4.  2019.  A later instalment of the same series.

1. 40a.

   Page 3:  “For more than 25 years, I have been reporting on the extension of fossil ranges either up or down within the geological column.” ↩

Reed, John K.  “Toppling the Timescale, Part III: Madness in the Methods.”  Creation Research Society Quarterly 45:6–17.  2008.  The third paper in Reed's series, examining the methods behind the timescale, biostratigraphy among them.

1. 41a.

   Page 9:  “Biostratigraphy is the use of index fossils to assign ages to the rocks that contain them. As has been noted by many creationists, the argument is circular because the deep time of evolution is a presupposition of the method. Yet, it remains the standard for much of the fossil-bearing strata.” ↩

Ross, Marcus R.  “Improving our understanding of creation and its history.”  Journal of Creation 28(2):62–63.  2014.  A letter by a young-earth paleontologist answering Tas Walker's claim that the column is not a physical reality.  It uses a mosasaur and impact-debris correlation between New Jersey and the Netherlands to show how long-distance correlation is done.

1. 42a.

   Page 62:  “Five mosasaur genera are found among the sandy clay sediments of New Jersey (US), with the highest fossils located just below an erosional scar that in nearby boreholes preserves a layer of impact debris consisting of shocked quartz, anomalous clay deposits, and elevated iridium levels. Across the Atlantic, in the chalk deposits of Maastricht (the Netherlands), four of the same mosasaur genera are present, and the highest fossils are once again found below a layer of impact debris containing similar materials to those in New Jersey”. ↩

2. 42b.

   Page 62:  “The correlation of these sections is robust, based on empirical, verifiable field data, and geologists refer to them as 'upper Cretaceous' and 'Maastrichtian' due to observable patterns of fossils and rocks, not 'hidden assumptions' or 'bias'.” ↩

3. 42c.

   Page 62:  “Claiming that the column is "not a physical reality" isn't just wrong, it misses the point: the column is a construct based on observable, real-world relationships.” ↩

Clarey, Timothy L.  “South Fork and Heart Mountain faults: examples of catastrophic, gravity-driven "overthrusts," northwest Wyoming, USA.”  Proceedings of the Seventh International Conference on Creationism.  2013.  A paper by an Institute for Creation Research geologist offering a Flood-time gravity-slide explanation for two large Wyoming fault systems, and telling creationists to stop denying that overthrusts exist.

1. 43a.

   Section Introduction:  “Today, however, creationists must accept the results of 100s of drill-hole penetrations and 1000s of kilometers of seismic reflection data, collected since the 1970s, proving the existence of many overthrust faults”.  “Authors who are critical of the geologic column should no longer use the denial of overthrusts as part of their argument.” ↩ ↩

Woodmorappe, John.  “The essential nonexistence of the evolutionary-uniformitarian geologic column: a quantitative assessment.”  Creation Research Society Quarterly 18(1):46–71.  1981.  A young-earth study that mapped rocks assigned to ten periods, Cambrian to Tertiary, on an equal-area grid of the continents, from a Soviet compilation and other sources, and counted how many periods each part of the land holds and how often each period rests on the next older one.  It is the standard creationist source on how incomplete the column is.

1. 44a.

   Page 67:  “nearly 13% of the earth's land surface has 5 geologic periods represented (irrespective of their order or identity) while slightly less than 1% has all 10 periods simultaneously in place. From the cumulative frequency curve in Figure 1, it can be seen that 42% of earth's land surface has 3 or less geologic periods present at all; 66% has 5 or less of the 10 present; and only 14% has 8 or more geologic periods represented at all.”  “Individual geologic periods' coverage of the earth's land surface range from a high of just over 51% for Cretaceous (Fig. 2) to a low of only 33% for Triassic.” ↩

2. 44b.

   Page 69:  “The successional liberties of Jurassic and Cretaceous (Table 2) may support the position that they are post Flood”. ↩

Austin, Steven A. et al.  “Catastrophic Plate Tectonics: A Global Flood Model of Earth History.”  Proceedings of the Third International Conference on Creationism, 609–622.  Pittsburgh: Creation Science Fellowship.  Edited by R. E. Walsh.  1994.  The founding paper of the catastrophic plate tectonics model of the Flood, by six young-earth scientists.  It tentatively places the end of the Flood near the Cretaceous/Tertiary boundary.

1. 45a.

   Page 614, section POST-FLOOD DYNAMICS — Flood/Post-Flood Boundary:  “The definition of the Flood/Post-Flood boundary in the geologic column is a subject of considerable dispute among creationists.”  “Therefore, we tentatively place the Flood/post-Flood boundary at approximately the Cretaceous/Tertiary (K/T) boundary.” ↩ ↩

Austin, Steven A., and Kurt P. Wise.  “The pre-Flood/Flood boundary: as defined in Grand Canyon, Arizona and eastern Mojave Desert, California.”  Proceedings of the Third International Conference on Creationism, 37–47.  Pittsburgh: Creation Science Fellowship.  Edited by R. E. Walsh.  1994.  A paper proposing five tests for the start of the Flood in the rock record:  an erosional break, older clasts above it, tectonic disturbance, a new sedimentary sequence and a jump in fossils.  It applies them in the Grand Canyon and the eastern Mojave.  Mirror:  Static.icr.org

1. 46a.

   Section Abstract:  “Only low-abundance microfossils are known below the unconformity, whereas undisputed animal fossils occur only above the Sixtymile Formation, and there in great abundance (PD). We believe, therefore, that the Sixtymile Formation is the oldest preserved Flood deposit in Grand Canyon of Arizona.” ↩ ↩

2. 46b.

   Section Conclusion and discussion:  “It has been common to assign the pre-Flood/Flood boundary to the Precambrian/Cambrian boundary. In the eastern Mojave, where the Precambrian/Cambrian boundary is gradational and unassociated with an unconformity, these definitions fail to produce an unambiguous pre-Flood/Flood boundary.” ↩

Snelling, Andrew A.  “The Geology of Israel within the Biblical Creation-Flood Framework of History: 2. The Flood Rocks.”  Answers Research Journal 3:267–309.  2010.  Snelling's study of the Flood-deposited rocks of Israel, which places the end of the Flood there in the Oligocene.

1. 47a.

   Pages 304–305:  “it seems more reasonable to place the Flood/post-Flood boundary in the geologic record of Israel in the Oligocene, or at the end of it.” ↩

Snelling, Andrew A.  “Locating the Flood/post-Flood Boundary Using the Relative Dating of the Weathering of Ore Deposits.”  Proceedings of the Eighth International Conference on Creationism, 553–566.  Creation Science Fellowship.  Edited by J. H. Whitmore.  2018.  A conference paper using the order of weathering minerals in ore deposits to argue for a Flood/post-Flood boundary at the Cretaceous/Paleogene line.

1. 48a.

   Page 560:  “The relative ages of supergene minerals thus favor a placement at the K-Pg boundary with a relative age of 66 Ma, the Flood/post-Flood boundary favored by many Flood geologists.” ↩

Snelling, Andrew A.  “The Petrology of the Tapeats Sandstone, Tonto Group, Grand Canyon, Arizona.”  Answers Research Journal 14:159–254.  2021.  A 96-page petrology study of the Cambrian sandstone at the base of the Grand Canyon's Paleozoic rocks by a geologist at Answers in Genesis, read in a Flood framework.

1. 49a.

   Page 240:  “However, before the Tapeats Sandstone was deposited there had to be a prolonged period (days or more) in which there was a significant amount of continental-scale erosion to bevel the Precambrian (pre-Flood) land surface to produce the Great Unconformity.” ↩ ↩

Whitmore, John H., and Paul Garner.  “Using Suites of Criteria to Recognize Pre-Flood, Flood, and Post-Flood Strata in the Rock Record with Application to Wyoming (USA).”  Proceedings of the Sixth International Conference on Creationism, 425–448.  Edited by A. A. Snelling.  2008.  A paper by two young-earth geologists proposing 27 criteria for telling pre-Flood, Flood and post-Flood rock apart, applied to a section in Wyoming.

1. 50a.

   Page 436:  “We conclude, therefore, that in our Wyoming section, the Flood/post-Flood boundary falls approximately during Lance to Fort Union Time (the Cretaceous/Tertiary boundary occurs after the Lance).” ↩

Ross, Marcus R.  “Evaluating potential post-Flood boundaries with biostratigraphy: the Pliocene/Pleistocene boundary.”  Journal of Creation 26(2):82–87.  2012.  A paper in the creationist Journal of Creation.  It takes 303 North American mammal genera from 28 terrestrial mammal families, as recorded in the Paleobiology Database, and asks how many have fossils on both sides of the Pliocene/Pleistocene line.  It finds that 23% of genera cross that line, and nearly every family does, and it argues that the boundary should lie lower, at a sharper biostratigraphic break.  The article uses it as the first quantitative test of the fossil objection to a late-Cenozoic boundary.

1. 51a.

   Page 87:  “At present, the Cretaceous/Paleogene boundary appears to be the stratigraphically highest and most prominent biostratigraphic break (it includes the last in-place stratigraphic appearance of dinosaurs, pterosaurs, and several other bird, mammal, reptile, and amphibian groups), though a similarly thorough analysis must be completed in order to strengthen its claim to the Flood/post-Flood boundary.” ↩

Tomkins, Jeffrey P., and Timothy L. Clarey.  “A Comprehensive Model of the Global Flood Based on Paleontology.”  Proceedings of the Ninth International Conference on Creationism 9:561–587.  2023.  An Institute for Creation Research paper that builds a Flood model from paleontology and places the end of the Flood at the top of the Neogene.

1. 52a.

   Page 581:  “Thus, the end of the global Flood is most likely defined as the upper margin of the Neogene system (just before the Quaternary at the top of the Cenozoic).  It is thus called the N-Q Flood Boundary (Clarey 2020).” ↩

Clarey, Timothy.  “Conventional Science Still Struggling to Exhume the Great Unconformity.”  Creation Science Update, Institute for Creation Research, article 15828.  2026.  A short Institute for Creation Research news piece replying to a 2026 study of the Great Unconformity.  It moves the Flood's onset down to the Great Nonconformity, one surface below the Great Unconformity.

1. 53a.

   “But the results of this study do support an earlier beginning to the massive erosional event that likely marked the onset of the global Flood.  This earlier erosional surface is known as the Great Nonconformity at Grand Canyon, possibly marking the beginning of the Flood. …  Furthermore, this suggests that many Proterozoic (Precambrian) sediments may have also been part of the Genesis Flood.” ↩ ↩

Oard, Michael J.  “The geological column is a general Flood order with many exceptions.”  Journal of Creation 24(2):78–82.  2010.  A companion paper that classifies the rocks with Tas Walker's biblical geologic model instead of the column, and compares the two.

1. 54a.

   Page 78, section Abstract:  “First, sedimentary rocks labeled Precambrian (if from the Flood), Paleozoic, and Mesozoic strata are early Flood. Second, Cenozoic strata can be early Flood, late Flood, or post-Flood depending upon the location and the particular fossil used to define the Cenozoic.” ↩ ↩

Holt, Roy D.  “Evidence for a Late Cainozoic Flood/post-Flood Boundary.”  CEN Technical Journal 10(1):128–167.  1996.  A paper testing sediment volume, volcanism, sea level, the mountains of Ararat and fossil fuels against possible Flood boundaries, concluding for a boundary in or after the mid-Pleistocene.

1. 55a.

   Page 161:  “Evidences from (1) global sediment and post-Flood erosion, (2) volcanism and climatic impact, (3) changes in the global sea level, (4) formation of the Mountains of Ararat, and (5) the formation of fossil fuels, place the Flood/post-Flood boundary during or after the mid-Pleistocene.” ↩

Walker, Tas.  “A biblical geologic model.”  Proceedings of the Third International Conference on Creationism, 581–592.  Pittsburgh: Creation Science Fellowship.  Edited by R. E. Walsh.  1994.  A proposal by an Australian engineer to classify rocks by biblical history, Creation, Flood and post-Flood, with named stages and phases, instead of by the column.

1. 56a.

   Page 581, section Abstract:  “The paper proposes that the model be tested against real geological sections and eventually used to reclassify geologic reference materials, such as maps, map commentaries, field guides, and handbooks, in terms of a Biblical model.” ↩ ↩

2. 56b.

   Page 586:  “No particular conditions are obvious from the Bible text to suggest distinctive features for each phase. Such criteria will need to be formulated as the model is applied in the field.” ↩ ↩

Garner, Paul et al.  “Flood models.”  TJ 14(3):79–80.  2000.  A letter in which the four authors of the 1996 papers that put the end of the Flood in the Palaeozoic say they are no longer satisfied with that model.

1. 57a.

   “None of us is satisfied with the model that we proposed in 1996.” ↩

Grand Canyon: Monument to Catastrophe.  Institute for Creation Research, Santee, California.  Edited by Steven A. Austin.  1994.  An edited book of chapters on the geology of the Grand Canyon from a young-earth view.

1. 58a.

   Page 57:  “Everywhere in northern Arizona these strata occur, they are bounded above by a very conspicuous planar surface of erosion (the 'Great Unconformity'), believed to represent early erosion and the onset of Noah's Flood.”  Page 67:  He generalises:  “Most creationist geologists regard the Great Unconformity as the feature formed during the tectonic and erosive catastrophe at the onset of Noah's Flood.” ↩

Clarey, Tim.  “Glacier National Park: Flood Sediments, Slides, and Ice Age Sculptures.”  Acts & Facts 55(4).  Jun 30, 2026.  A popular Institute for Creation Research article on the geology of Glacier National Park, Montana, which accepts the Lewis Thrust as a real fault and proposes that it slid on wet Flood sediment.

1. 59a.

   “This is referred to as the Lewis Thrust. Amazingly, it moved along a nearly horizontal fault surface, parallel to bedding, placing Belt rocks on top of much younger rocks.” ↩

Oard, Michael J.  “Fossil time ranges continue to expand up and down.”  Journal of Creation 31(2):3–5.  2017.  A short survey of fossil finds that extend known ranges, part of a series Oard has kept up for decades.

1. 60a.

   Page 3:  “Some range expansions are quite large, such as moving the time boundaries by 50 to 100 Ma or more.”  His examples follow:  eukaryotes, grass in dinosaur dung, Mesozoic mammals and flowering plants. ↩

Sedgwick, Adam.  “Address to the Geological Society, delivered on the evening of the 18th of February 1831, on retiring from the President's Chair.”  Proceedings of the Geological Society of London 1(20):281–316.  1831.  The presidential address in which the Cambridge geologist, an Anglican clergyman who four years later named the Cambrian, publicly withdrew his earlier view that the superficial gravels were laid down by Noah's Flood.

1. 61a.

   Page 313:  “Our errors were, however, natural, and of the same kind which led many excellent observers of a former century to refer all the secondary formations of geology to the Noachian deluge.”  “thus publicly to read my recantation.” ↩