The Age of the Earth
Leibnitz reworked Descartes’s cosmogony. Protogea was published much later in An essay toward a Natural History of the Earth. Woodward came down fairly strongly for the view that the flood was an act of God that could not be accounted for by normal physical processes. He also postulated hydrological sorting to account for the ordering of fossils. Whiston added comets to Burnet’s cosmogony as the source of the waters of the flood. Lectures and Discourse of Earthquakes and Subterranean Eruptions. Hooke believed that the fossils were the remains of extinct species and could not be accounted for by the Flood.
The Age of the Earth
Can science prove the age of the earth? No scientific method can prove the age of the earth and the universe, and that includes the ones we have listed here. Further, it has to be assumed that the clock was never disturbed. There is no independent natural clock against which those assumptions can be tested.
How radiometric dating works in general: Radioactive elements decay gradually into other elements. The original element is called the parent, and the result of the decay process is .
This age is obtained from radiometric dating and is assumed by evolutionists to provide a sufficiently long time-frame for Darwinian evolution. And OE Christians theistic evolutionists see no problem with this dating whilst still accepting biblical creation, see Radiometric Dating – A Christian Perspective. This is the crucial point: Some claim Genesis in particular, and the Bible in general looks mythical from this standpoint.
A full discussion of the topic must therefore include the current scientific challenge to the OE concept. This challenge is mainly headed by Creationism which teaches a young-earth YE theory. A young earth is considered to be typically just 6, years old since this fits the creation account and some dating deductions from Genesis.
The crucial point here is: Accepted Dating Methods Here we outline some dating methods , both absolute and relative, that are widely accepted and used by the scientific community. Absolute dating supplies a numerical date whilst relative dating places events in time-sequence; both are scientifically useful. Radiometric Dating This is based upon the spontaneous breakdown or decay of atomic nuclei.
Radioactive parent P atoms decay to stable daughter D atoms e. The time required for half the original number of parent atoms to decay is called the half life.
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The Radiometric Dating Game Radiometric dating methods estimate the age of rocks using calculations based on the decay rates of radioactive elements such as uranium, strontium, and potassium. On the surface, radiometric dating methods appear to give powerful support to the statement that life has existed on the earth for hundreds of millions, even billions, of years. We are told that these methods are accurate to a few percent, and that there are many different methods. We are told that of all the radiometric dates that are measured, only a few percent are anomalous.
In dating: Fission-track dating during the spontaneous fission of uranium In this unique type of radioactive decay, the nucleus of a single parent uranium atom splits into two fragments of similar mass with such force that a trail of crystal damage is left in the mineral.
Roman poet Lucretius, intellectual heir to the Greek atomists, believed its formation must have been relatively recent, given that there were no records going back beyond the Trojan War. The Talmudic rabbis, Martin Luther and others used the biblical account to extrapolate back from known history and came up with rather similar estimates for when the earth came into being. Within decades observation began overtaking such thinking. In the s Nicolas Steno formulated our modern concepts of deposition of horizontal strata.
He inferred that where the layers are not horizontal, they must have been tilted since their deposition and noted that different strata contain different kinds of fossil. This position came to be known as uniformitarianism, but within it we must distinguish between uniformity of natural law which nearly all of us would accept and the increasingly questionable assumptions of uniformity of process, uniformity of rate and uniformity of outcome.
That is the background to the intellectual drama being played out in this series of papers. It is a drama consisting of a prologue and three acts, complex characters, and no clear heroes or villains. We, of course, know the final outcome, but we should not let that influence our appreciation of the story as it unfolds. Even less should we let that knowledge influence our judgment of the players, acting as they did in their own time, constrained by the concepts and data then available.
Changing Views of the History of the Earth
Relative dating Studies of strata , the layering of rocks and earth, gave naturalists an appreciation that Earth may have been through many changes during its existence. These layers often contained fossilized remains of unknown creatures, leading some to interpret a progression of organisms from layer to layer. Lomonosov’s ideas were mostly speculative. In the Comte du Buffon tried to obtain a value for the age of Earth using an experiment:
Carbon dating is used to determine the age of biological artifacts up to 50, years old. This technique is widely used on recent artifacts, but educators and students alike should note that this technique will not work on older fossils (like those of the dinosaurs alleged to be millions of years old).
It is ductile, malleable , and capable of taking a high polish. In air the metal tarnishes and when finely divided breaks into flames. It is a relatively poor conductor of electricity. The formulation of the periodic system by Russian chemist Dmitry Mendeleyev in focused attention on uranium as the heaviest chemical element, a position that it held until the discovery of the first transuranium element neptunium in In the French physicist Henri Becquerel discovered in uranium the phenomenon of radioactivity , a term first used in by French physicists Marie and Pierre Curie.
This property was later found in many other elements. It is now known that uranium, radioactive in all its isotopes , consists naturally of a mixture of uranium Uranium is the parent and uranium one of the daughters in the radioactive uranium decay series ; uranium is the parent of the actinium decay series. See also actinoid element. The element uranium became the subject of intense study and broad interest after German chemists Otto Hahn and Fritz Strassmann discovered in late the phenomenon of nuclear fission in uranium bombarded by slow neutrons.
Italian-born American physicist Enrico Fermi suggested early that neutrons might be among the fission products and could thus continue the fission as a chain reaction. Those discoveries led to the first self-sustaining nuclear chain reaction December 2, , the first atomic bomb test July 16, , the first atomic bomb dropped in warfare August 6, , the first atomic-powered submarine , and the first full-scale nuclear-powered electrical generator Fission occurs with slow neutrons in the relatively rare isotope uranium the only naturally occurring fissile material , which must be separated from the plentiful isotope uranium for its various uses.
Uranium , however, after absorbing neutrons and undergoing negative beta decay , is transmuted into the synthetic element plutonium , which is fissile with slow neutrons.
Age of the earth
Carbon , Radiometric Dating and Index Fossils Carbon dating is used to determine the age of biological artifacts up to 50, years old. This technique is widely used on recent artifacts, but educators and students alike should note that this technique will not work on older fossils like those of the dinosaurs alleged to be millions of years old. This technique is not restricted to bones; it can also be used on cloth, wood and plant fibers.
Carbon dating has been used successfully on the Dead Sea Scrolls, Minoan ruins and tombs of the pharaohs among other things. Carbon is a radioactive isotope of carbon. The half-life of carbon is approximately 5, years.
The pre-scientific period before AD In the pre-scientific era the Biblical account and the speculations of the Greek philosophers were accepted without great question.
Reference to a case where the given method did not work This is perhaps the most common objection of all. Creationists point to instances where a given method produced a result that is clearly wrong, and then argue that therefore all such dates may be ignored. Such an argument fails on two counts: First, an instance where a method fails to work does not imply that it does not ever work.
The question is not whether there are “undatable” objects, but rather whether or not all objects cannot be dated by a given method. The fact that one wristwatch has failed to keep time properly cannot be used as a justification for discarding all watches. How many creationists would see the same time on five different clocks and then feel free to ignore it?
Yet, when five radiometric dating methods agree on the age of one of the Earth’s oldest rock formations Dalrymple , p.
How Science Figured Out the Age of Earth
The Oldest Living Thing: The oldest living thing on earth is either an Irish Oak or a Bristlecone pine. If we assume a growth rate of one tree ring per year, then the oldest trees are between 4, and 4, years old. Also, with regard to fossil tree rings, the author has been unable to find any documented instances of fossil trees having more than about rings.
This is significant since we are told that God literally made the Earth, and all that is in it, only about years before the Noachian Flood described in the Book of Genesis.
The age of the Earth is ± billion years ( × 10 9 years ± 1%). This age may represent the age of the Earth’s accretion, of core formation, or of the material from which the Earth formed. This dating is based on evidence from radiometric age-dating of meteorite material and is consistent with the radiometric ages of the oldest-known terrestrial and lunar samples.
Paleovalley-related uranium resources include sandstone-, lignite- and calcrete-style deposits that are developed within the host sediments deposited in paleovalleys. The critical features of paleovalley-related uranium deposits include sediment and uranium sources, geological setting, depositional environment, age and relative timing of mineralization, aquifer characteristics, availability and distribution of reductants, and preservation potential of the uranium mineral system.
This set of information provides a basis to establish the uranium mineralization model, which can then be used to assist with generating targets for uranium exploration and prospectivity analysis of a region. With respect to Sino-Australian examples, paleovalley-related uranium deposits form mostly around the margins of sedimentary basins and the mineralization is commonly hosted within channel fills contained within paleovalleys developed upon, or proximal to, Precambrian crystalline rocks that contain primary uranium sources.
The deposits that have been well studied show remarkably similar factors that controlled the formation of paleovalley-related uranium deposits. In these regions, extensive fluvial systems developed particularly during Mesozoic and Cenozoic times, uranium from the bedrock was first dispersed into the sediments, and then concentrated to form deposits through successive chemical remobilization, precipitation and concentration. The mineralization is developed where oxidizing fluids carrying dissolved U reacted with reductants in the sediments.
Geological, geophysical and geochemical features of the paleovalleys and related uranium deposits are used to construct models to understand host sediment distribution, fluid flow and ore genesis that can assist exploration for paleovalley-hosted uranium deposits.
At the time that Darwin’s On the Origin of Species was published, the earth was “scientifically” determined to be million years old. By , it was found to be 1. In , science firmly established that the earth was 3. Finally in , it was discovered that the earth is “really” 4. In these early studies the order of sedimentary rocks and structures were used to date geologic time periods and events in a relative way.
Uranium–lead dating, abbreviated U–Pb dating, is one of the oldest and most refined of the radiometric dating schemes. It can be used to date rocks that formed and crystallised from about 1 million years to over billion years ago with routine precisions in the –1 percent range.. The dating method is usually performed on the mineral zircon.
Decay routes[ edit ] The above uranium to lead decay routes occur via a series of alpha and beta decays, in which U with daughter nuclides undergo total eight alpha and six beta decays whereas U with daughters only experience seven alpha and four beta decays. The term U—Pb dating normally implies the coupled use of both decay schemes in the ‘concordia diagram’ see below. However, use of a single decay scheme usually U to Pb leads to the U—Pb isochron dating method, analogous to the rubidium—strontium dating method.
Finally, ages can also be determined from the U—Pb system by analysis of Pb isotope ratios alone. This is termed the lead—lead dating method. Clair Cameron Patterson , an American geochemist who pioneered studies of uranium—lead radiometric dating methods, is famous for having used it to obtain one of the earliest estimates of the age of the Earth. Mineralogy[ edit ] Although zircon ZrSiO4 is most commonly used, other minerals such as monazite see: Where crystals such as zircon with uranium and thorium inclusions do not occur, a better, more inclusive, model of the data must be applied.
These types of minerals often produce lower precision ages than igneous and metamorphic minerals traditionally used for age dating, but are more common in the geologic record.
Age of the Earth
Tabular[ edit ] Tabular deposits consist of irregular tabular or elongate lenticular zones of uranium mineralisation within selectively reduced sediments. The mineralised zones are oriented parallel to the direction of groundwater flow, but on a small scale the ore zones may cut across sedimentary features of the host sandstone. Tabular sandstone uranium deposits contains many of the highest grades of the sandstone class, however the average deposit size is very small.
Roll front[ edit ] Structures interpreted as Palaeo-rollfronts in South Australia Roll-front uranium deposits are generally hosted within permeable and porous sandstones or conglomerates. The mechanism for deposit formation is dissolution of uranium from the formation or nearby strata and the transport of this soluble uranium into the host unit.
How Science Figured Out the Age of Earth. For centuries scholars sought to determine Earth’s age, but the answer had to wait for careful geologic observation, isotopic analyses of the elements.
View images by clicking on link or reduced image: Each image opens into a new window. These primitive, medium sized apes lived in rain forests between 18 and 22 million years ago. This species and others such as Dryopithecus existed before the hominid line diverged on the path to humans. This lineage ancestral gibbons is believed to have diverged from the great ape and human lineages between 17 and 25 Mya Avers, Oreopithecus ‘s hand closely matches the pattern of early hominids, with a grasping capability including firm pad-to-pad precision gripping that apes are unable to perform presumably as a response to similar functional demands to hominids Moya-Sola et al, Bipedal activities made up a significant part of the positional behavior of this primate Kohler and Moya-Sola, Gorilla and human DNA only differs by 2.