Slowly and painstakingly, geologists have assembled this record into the generalized geologic time scale shown in Figure 1. This was done by observing the relative age sequence of rock units in a given area and determining, from stratigraphic relations, which rock units are younger, which are older, and what assemblages of fossils are contained in each unit. Using fossils to correlate from area to area, geologists have been able to work out a relative worldwide order of rock formations and to divide the rock record and geologic time into the eras, periods, and epochs shown in Figure 1. The last modification to the geologic time scale of Figure 1 was in the s, before radiometric dating was fully developed, when the Oligocene Epoch was inserted between the Eocene and the Miocene. Although early stratigraphers could determine the relative order of rock units and fossils, they could only estimate the lengths of time involved by observing the rates of present geologic processes and comparing the rocks produced by those processes with those preserved in the stratigraphic record. With the development of modern radiometric dating methods in the late s and s, it was possible for the first time not only to measure the lengths of the eras, periods, and epochs but also to check the relative order of these geologic time units. Radiometric dating verified that the relative time scale determined by stratigraphers and paleontologists Figure 1 is absolutely correct, a result that could only have been obtained if both the relative time scale and radiometric dating methods were correct. Nonetheless, stratigraphy and radiometric dating of Precambrian rocks have clearly demonstrated that the history of the Earth extends billions of years into the past. Radiometric dating has not been applied to just a few selected rocks from the geologic record. Literally many tens of thousands of radiometric age measurements are documented in the scientific literature.
Welcome to Understanding Geologic Time
What is the age of the earth? How old is the earth? On some topics, the Bible is extremely clear. For example, our moral obligations toward God and the method of salvation are discussed in detail. Reading the Scriptures carefully, one finds that the more critical a topic is, the more directly the Bible addresses it. There are several ways of attempting to determine the age of the earth.
Question: “What is the age of the earth? How old is the earth?” Answer: On some topics, the Bible is extremely clear. For example, our moral obligations toward God and the method of salvation are discussed in detail. On other topics, however, the Bible doesn’t provide nearly as much information.
Shop Now Scientists use a technique called radiometric dating to estimate the ages of rocks, fossils, and the earth. Many people have been led to believe that radiometric dating methods have proved the earth to be billions of years old. With our focus on one particular form of radiometric dating—carbon dating—we will see that carbon dating strongly supports a young earth.
Note that, contrary to a popular misconception, carbon dating is not used to date rocks at millions of years old. Basics Before we get into the details of how radiometric dating methods are used, we need to review some preliminary concepts from chemistry. Recall that atoms are the basic building blocks of matter. Atoms are made up of much smaller particles called protons, neutrons, and electrons. Protons and neutrons make up the center nucleus of the atom, and electrons form shells around the nucleus.
The number of protons in the nucleus of an atom determines the element. For example, all carbon atoms have 6 protons, all atoms of nitrogen have 7 protons, and all oxygen atoms have 8 protons. The number of neutrons in the nucleus can vary in any given type of atom.
What is the age of the earth How old is the earth
Early history[ edit ] In Ancient Greece , Aristotle BCE observed that fossils of seashells in rocks resembled those found on beaches — he inferred that the fossils in rocks were formed by living animals, and he reasoned that the positions of land and sea had changed over long periods of time. Leonardo da Vinci — concurred with Aristotle’s interpretation that fossils represented the remains of ancient life.
Steno argued that rock layers or strata were laid down in succession, and that each represents a “slice” of time. He also formulated the law of superposition, which states that any given stratum is probably older than those above it and younger than those below it. While Steno’s principles were simple, applying them proved challenging.
Archaeologists use the exponential, radioactive decay of carbon 14 to estimate the death dates of organic material. The stable form of carbon is carbon 12 and the radioactive isotope carbon 14 decays over time into nitrogen 14 and other particles.
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.
The claim that the methods produce bad results essentially at random does not explain why these “bad results” are so consistently in line with mainstream science. Claims that the assumptions of a method may be violated Certain requirements are involved with all radiometric dating methods. These generally include constancy of decay rate and lack of contamination gain or loss of parent or daughter isotope.
The Age of the Earth: G. Brent Dalrymple: : Books
What is radiocarbon dating? This isotope lets scientists learn the ages of once-living things. Radiocarbon dating is a technique used by scientists to learn the ages of biological specimens — for example, wooden archaeological artifacts or ancient human remains — from the distant past. It can be used on objects as old as about 62, years. What is an isotope?
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.
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.
Carbon 14 Dating
How Can We Know? Can we determine the age of the earth, and if so, how? Scientists generally agree that the answer to the riddle of the age of the earth is carefully concealed within the earth’s crust. Thus, the geologic timescale and radiometric dating have been developed in an effort to determine the age of the earth. The older of the two dating methods, the geologic timescale, is actually a circular argument and is therefore considered by many scholars to be weak.
Nevertheless, the geologic timescale was thought to have been redeemed and refined with the advent of radiometric dating.
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.
For example, back in , Lord Kelvin calculated how long Earth might have taken to cool from its original molten state. He concluded that Earth was born 20 to million years ago. Their message proved difficult to decipher. How old is Earth? However, from working with layer upon layer of rock laid down on Earth over long time spans, early 20th century scientists came to believe Earth not millions of years old — but billions of years old. Modern radiometric dating methods came into prominence in the late s and s.
These methods focus on the decay of atoms of one chemical element into another. They led to the discovery that certain very heavy elements could decay into lighter elements — such as uranium decaying into lead. This work gave rise to a process known as radiometric dating. This technique is based on a comparison between the measured amount of a naturally occurring radioactive element and its decay products, assuming a constant rate of decay — known as a half-life.
Over the decades of the 20th century, scientists documented tens of thousands of radiometric age measurements. Likewise, scientists use radiometric dating to determine the ages of moon rocks, obtained by astronauts.
Age of the Earth: strengths and weaknesses of dating methods
The first Sumerian king Alulim , at Eridu , is described as reigning for 28, years, followed by several later kings of similar periods. In total these antediluvian kings ruled for , years from the time when “the kingship was lowered from heaven” to the time when “the flood” swept over the land. A layer of riverine sediments, radiocarbon dated to ca. Polychrome pottery from the Jemdet Nasr period — BC was discovered immediately below the Shuruppak flood stratum. The “flood” described in the Sumerian King List, is believed to have a historical basis, and has been dated BC.
Instead they believed that these figures were either fabrications, or were based on not literal solar years
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 .
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. This gives us the impression that all but a small percentage of the dates computed by radiometric methods agree with the assumed ages of the rocks in which they are found, and that all of these various methods almost always give ages that agree with each other to within a few percentage points. Since there doesn’t seem to be any systematic error that could cause so many methods to agree with each other so often, it seems that there is no other rational conclusion than to accept these dates as accurate.
However, this causes a problem for those who believe based on the Bible that life has only existed on the earth for a few thousand years, since fossils are found in rocks that are dated to be over million years old by radiometric methods, and some fossils are found in rocks that are dated to be billions of years old. If these dates are correct, this calls the Biblical account of a recent creation of life into question.
After study and discussion of this question, I now believe that the claimed accuracy of radiometric dating methods is a result of a great misunderstanding of the data, and that the various methods hardly ever agree with each other, and often do not agree with the assumed ages of the rocks in which they are found. I believe that there is a great need for this information to be made known, so I am making this article available in the hopes that it will enlighten others who are considering these questions.
How Old is the Earth: Scientific Age of the 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.
The question of the age of the earth has produced heated discussions on Internet debate boards, TV, radio, in classrooms, and in many churches, Christian colleges, and seminaries. The primary sides are Young-earth proponents (biblical age of the earth and universe of about 6, years)1 Old-earth.
As Creation magazine has been continuously published since , we are publishing some of the articles from the archives for historical interest, such as this. For teaching and sharing purposes, readers are advised to supplement these historic articles with more up-to-date ones suggested in the Related Articles and Further Reading below. The radiometric evidence for a 4. The basic theory of radiometric dating is briefly reviewed. Since the estimate for the age of the Earth has been based on the assumption that certain meteorite lead isotope ratios are equivalent to the primordial lead isotope ratios on Earth.
In this assumption was shown to be highly questionable. Despite this, the momentum gained in the two decades prior to has made 4. Some evidence is also presented to show that radiometric results that are in agreement with the accepted geological time scale are selectively published in preference to those results that are not in agreement. Basics The geological time scale and an age for the Earth of 4.
Unreliability of Radiometric Dating and Old Age of the Earth
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.
G. Dalrymple has done a wonderful job in writing such a technical work on the history and direct data for the current estimate of the age of the Earth being Billion years old and the Universe being 7 – .
The stable form of carbon is carbon 12 and the radioactive isotope carbon 14 decays over time into nitrogen 14 and other particles. Carbon is naturally in all living organisms and is replenished in the tissues by eating other organisms or by breathing air that contains carbon. At any particular time all living organisms have approximately the same ratio of carbon 12 to carbon 14 in their tissues.
When an organism dies it ceases to replenish carbon in its tissues and the decay of carbon 14 to nitrogen 14 changes the ratio of carbon 12 to carbon Experts can compare the ratio of carbon 12 to carbon 14 in dead material to the ratio when the organism was alive to estimate the date of its death. Radiocarbon dating can be used on samples of bone, cloth, wood and plant fibers. The half-life of a radioactive isotope describes the amount of time that it takes half of the isotope in a sample to decay.
In the case of radiocarbon dating, the half-life of carbon 14 is 5, years. This half life is a relatively small number, which means that carbon 14 dating is not particularly helpful for very recent deaths and deaths more than 50, years ago. After 5, years, the amount of carbon 14 left in the body is half of the original amount. If the amount of carbon 14 is halved every 5, years, it will not take very long to reach an amount that is too small to analyze. When finding the age of an organic organism we need to consider the half-life of carbon 14 as well as the rate of decay, which is —0.
How old is the fossil? We can use a formula for carbon 14 dating to find the answer.