Flood geology
Flood geology is a pseudoscientific attempt to interpret and reconcile geological features of the Earth in accordance with a literal belief in the Genesis flood narrative, the flood myth in the Hebrew Bible. In the early 19th century, diluvial geologists hypothesized that specific surface features provided evidence of a worldwide flood which had followed earlier geological eras; after further investigation they agreed that these features resulted from local floods or from glaciers. In the 20th century, young-Earth creationists revived flood geology as an overarching concept in their opposition to evolution, assuming a recent six-day Creation and cataclysmic geological changes during the biblical flood, and incorporating creationist explanations of the sequences of rock strata.
In the early stages of development of the science of geology, fossils were interpreted as evidence of past flooding. The "theories of the Earth" of the 17th century proposed mechanisms based on natural laws, within a timescale set by the Ussher chronology. As modern geology developed, geologists found evidence of an ancient Earth and evidence inconsistent with the notion that the Earth had developed in a series of cataclysms, like the Genesis flood. In early 19th-century Britain, "diluvialism" attributed landforms and surface features to the destructive effects of this supposed global deluge, but by 1830 geologists increasingly found that the evidence supported only relatively local floods. So-called scriptural geologists attempted to give primacy to literal biblical explanations, but they lacked a background in geology and were marginalised by the scientific community, as well as having little influence in the churches.
Creationist flood geology was only supported by a minority of the 20th century anti-evolution movement, mainly in the Seventh-day Adventist Church, until the 1961 publication of The Genesis Flood by Morris and Whitcomb. Around 1970, proponents adopted the terms "scientific creationism" and creation science.
Proponents of flood geology hold to a literal reading of Genesis 6–9 and view its passages as historically accurate; they use the Bible's internal chronology to place the Genesis flood and the story of Noah's Ark within the last 5,000 years.
Scientific analysis has refuted the key tenets of flood geology. Flood geology contradicts the scientific consensus in geology, stratigraphy, geophysics, physics, paleontology, biology, anthropology, and archaeology. Modern geology, its sub-disciplines and other scientific disciplines use the scientific method. In contrast, flood geology does not adhere to the scientific method, making it a pseudoscience.
History of theories
In pre-Christian times, fossils found on land were thought by Greek philosophers—including Xenophanes, Xanthus and Aristotle—to be evidence that the sea had in past ages covered the land. Their concept of vast time periods in an eternal cosmos was rejected by early Christian writers as incompatible with their belief in Creation by God. Among the church fathers, Tertullian spoke of fossils demonstrating that mountains had been overrun by water without explicitly saying when. Chrysostom and Augustine believed that fossils were the remains of animals that were killed and buried during the brief duration of the Genesis flood, and later Martin Luther viewed fossils as having resulted from the flood. The earliest documentation of the famous fossil fishes of the Sannine Formation comes from Eusebius, who cites them as being evidence of the Biblical flood.Other scholars, including Avicenna, thought fossils were produced in the rock by "petrifying virtue" acting on "seeds" of plants and animals. In 1580, Bernard Palissy speculated that fossils had formed in lakes, and natural historians subsequently disputed the alternatives. Robert Hooke made empirical investigations and doubted that the numbers of fossil shells or depth of shell beds could have formed in the one year of Noah's flood. In 1616, Nicolas Steno showed how chemical processes changed organic remains into stone fossils. His fundamental principles of stratigraphy published in 1669 established that rock strata formed horizontally and were later broken and tilted, though he assumed these processes would occur within 6,000 years including a worldwide flood.
Theories of the Earth
In his influential Principles of Philosophy of 1644, René Descartes applied his mechanical physical laws to envisage swirling particles forming the Earth as a layered sphere. This natural philosophy was recast in biblical terms by the theologian Thomas Burnet, whose Sacred Theory of the Earth published in the 1680s proposed complex explanations based on natural laws, and explicitly rejected the simpler approach of invoking miracles as incompatible with the methodology of natural philosophy. Burnet maintained that less than 6,000 years ago the Earth had emerged from chaos as a perfect sphere, with paradise on land over a watery abyss. This crust had dried out and cracked, and its collapse caused the biblical deluge, forming mountains as well as caverns where the water retreated. He made no mention of fossils but inspired other diluvial theories that did.In 1695, John Woodward's An Essay Toward a Natural History of the Earth viewed the Genesis flood as dissolving rocks and soil into a thick slurry that caught up all living things, which, when the waters settled, formed strata according to the relative density of these materials, including fossils of the organisms. When it was pointed out that lower layers were often less dense and forces that shattered rock would destroy organic remains, he resorted to the explanation that a divine miracle had temporarily suspended gravity.
William Whiston's New Theory of the Earth of 1696 combined scripture with Newtonian physics to propose that the original chaos was the atmosphere of a comet with the days of creation each taking a year, and the Genesis flood had resulted from a second comet. His explanation of how the flood caused mountains and the fossil sequence was similar to Woodward's. Johann Jakob Scheuchzer wrote in support of Woodward's ideas in 1708, describing some fossil vertebrae as bones of sinners who had perished in the flood. A skeleton found in a quarry was described by him in 1726 as Homo diluvii testis, a giant human testifying to the flood. This was accepted for some time, but in 1812 it was shown to be a prehistoric salamander.
Beginnings of modern geology
The modern science of geology developed in the 18th century; the term "geology" was popularised by the Encyclopédie of 1751. Steno's categorisation of strata was expanded by several geologists, including Johann Gottlob Lehmann who believed that the oldest mountains had formed early in the Creation, and categorised as Flötz-Gebürge stratified mountains with few ore deposits but with thin layers containing fossils, overlain by a third category of superficial deposits. In his 1756 publication he identified 30 different layers in this category which he attributed to the action of the Genesis deluge, possibly including debris from the older mountains. Others including Giovanni Arduino attributed secondary strata to natural causes: Georg Christian Füchsel said that geologists had to take as standard the processes in which nature currently produces solids, "we know no other way", and only the most recent deposits could be attributed to a great flood.Lehman's classification was developed by Abraham Gottlob Werner who thought that rock strata had been deposited from a primeval global ocean rather than by Noah's flood, a doctrine called Neptunism. The idea of a young Earth was further undermined in 1774 by Nicolas Desmarest, whose studies of a succession of extinct volcanoes in Europe showed layers which would have taken long ages to build up. The fact that these layers were still intact indicated that any later flood had been local rather than universal. Against Neptunism, James Hutton proposed an indefinitely old cycle of eroded rocks being deposited in the sea, consolidated and heaved up by volcanic forces into mountains which in turn eroded, all in natural processes which continue to operate.
Catastrophism and diluvialism
The first professional geological society, the Geological Society of London, was founded in 1807. By this time, geologists were convinced that an immense time had been needed to build up the huge thickness of rock strata visible in quarries and cliffs, implying extensive pre-human periods. Most accepted a basic time scale classifying rocks as primitive, transition, secondary, or tertiary. Several researchers independently found that strata could be identified by characteristic fossils: secondary strata in southern England were mapped by William Smith from 1799 to 1815.Cuvier and Jameson
, working with Alexandre Brongniart, examined tertiary strata in the region around Paris. Cuvier found that fossils identified rock formations as alternating between marine and terrestrial deposits, indicating "repeated irruptions and retreats of the sea" which he identified with a long series of sudden catastrophes which had caused extinctions. In his 1812 Discours préliminaire to his Recherches sur les ossemens fossiles de quadrupeds put forward a synthesis of this research into the long prehistoric period, and a historical approach to the most recent catastrophe. His historical approach tested empirical claims in the biblical text of Genesis against other ancient writings to pick out the "real facts" from "interested fictions". In his assessment, Moses had written the account around 3,300 years ago, long after the events described. Cuvier only discussed the Genesis flood in general terms, as the most recent example of "an event of an universal catastrophe, occasioned by an irruption of the waters" not set "much further back than five or six thousand years ago". The historical texts could be loosely related to evidence such as overturned strata and "heaps of debris and rounded pebbles". An English translation was published in 1813 with a preface and notes by Robert Jameson, Regius Professor of Natural history at the University of Edinburgh. He began the preface with a sentence which ignored Cuvier's historical approach and instead deferred to revelation:This sentence was removed after the second edition, and Jameson's position changed as shown by his notes in successive editions, but it influenced British views of Cuvier's concept. In 1819, George Bellas Greenough, first president of The Geological Society, issued A Critical Examination of the First Principles of Geology stating that unless erratic boulders deposited hundreds of miles from their original sources had been moved by seas, rivers, or collapsing lakes, "the only remaining cause, to which these effects can be ascribed, is a Debacle or Deluge."