The Erosion of Continents as a Creationist Clock

By Kevin Mellem

Creationists and scientists have been debating for years about the age of the Earth and the universe. In this debate, the apparent decay of the Earth's magnetic field has been used by young-Earth creationists as evidence that the world is only thousands of years old, while scientists maintain that the cyclic nature of the magnetic field renders any age produced by magnetic field decay theory to be invalid. Careful analysis of both the creationist's and scientist's theories can provide a clearer picture of who is correct in this long-running debate.

The creationist argument is based on a theory that was proposed by Dr. Thomas Barnes in 1971 (Humphreys 1993). Using data obtained by Keith McDonald and Robert Gunst in 1967, Dr. Barnes asserted that Earth's magnetic field has been decaying in a non-cyclic manner at an exponential rate since the beginning of creation (Matson 2002). Barnes used the data of McDonald and Gunst to plot an exponential curve and, by extrapolating the observed data backward into time using his exponential decay equation, Barnes claimed that the magnetic field was approximately 40 percent stronger in 1000 A.D. than it is today (Sarfati 1998). Continuing this extrapolation, Barnes stated that the Earth must not be older than 10,000 years, or else the strength of the magnetic field would have been so large that it would have melted the Earth (Sarfati 1998).

Unfortunately for Dr. Barnes, observed scientific evidence has shown that Earth's magnetic field has not been decaying constantly since the dawn of creation. In fact, the magnetic field has fluctuated and reversed in polarity over time, proven by evidence of periods of increasing and decreasing field energy (Sarfati 1998). Due to this cyclic fluctuation, scientists have argued that the strength of the magnetic field cannot be used to determine an age for the earth, since it is a reversible, cyclic process (Stassin 2005). However, creationists have offered a solution to this potential problem. Dr. Russell Humphreys, a nuclear physicist, looks to the Genesis flood as the cause of the fluctuations in the magnetic field. Utilizing a creationist theory that the Genesis Flood was caused by the plunging of tectonic plates toward the Earth's core, Dr. Humphreys claims that the tectonic plates would have caused a sudden cooling of the outer parts of the Earth's core (Sarfati 1998). This sudden cooling would cause convection currents to flow within the core, which would generate numerous reversals of the magnetic field over the course of thousands of years (Humphreys 1993). These field reversals would have happened rapidly at the time of the Flood, according to Humphreys, leading to an increase in the intensity (strength and direction) of the magnetic field until it reached a maximum at the time of Jesus Christ. As shown in Fig. 1 below, Humphreys believes the intensity of the field has been decreasing since the time of Christ.

graph of the decreasing intensity of Earth's magnetic field

This graph raises as many questions as it answers. For instance, what was the state of the magnetic field before the flood? Humphreys himself provides no scientific answers to this specific question, instead focusing on his data and theories relating to the time of the Flood, which he denotes as the third millennium before Christ (Humphreys 1993).

Humphreys does, however, outline his theory of constant magnetic field decay, the dynamic-decay theory. According to this theory, Earth's magnetic field has been constantly losing about half its energy every 700 years (Humphreys 1993). Using assumptions that he himself has made about the maximum energy [it is important to note that energy is not the same concept as intensity] of the magnetic field at the time of creation, Humphreys produces the following figure, which shows an age vs. energy curve for both the dynamic-decay theory and a free decay theory similar to that of Barnes (Humphreys 1993).

energy-age graph

Based upon his assumptions that the energy of the magnetic field has been in a state of constant decay, and taking into account his theory that the Flood caused an accelerated rate of decay that led to a massive energy drop over a relatively short period of time, Humphreys concludes that the earth must only be about 6,000 years old (Humphreys 1993).

The scientific community has been quick to respond to the age data presented by creationists, and they have provided several counters to the claims of Barnes. Any flaws found in Barnes' work also discredit the work of Humphreys, since Humphreys' work is based upon that of Barnes. The first point made by scientists is that Barnes used an outdated model in his analysis of the Earth's interior (Matson 2002). By using an outdated model, any assumptions Barnes made become invalid. Second, by using McDonald's and Gunst's data, Barnes only analyzed the dipole component of the magnetic field, which is not an accurate measurement of the overall strength of the Earth's magnetic field (Matson 2002). Third, scientists show that the data used by Barnes more easily fits a linear curve than an exponential one, and Barnes chose an exponential curve based on incorrect assumptions (Thompson 1997).

The scientific answer for the apparent decay of the magnetic field was given by Dr. Walter Elsasser, a physicist at the University of Utah. According to Dr. Elsasser, Earth's magnetic field is generated by a dynamo within the Earth's core (Matson 2002). This dynamo is driven by an unknown energy source, but the subsequent fluid movement within the core generates the magnetic field around the Earth (Matson 2002). Creationists are quick to call this theory into question, because they see the fact that the energy source of the dynamo is unknown as evidence that the theory may be incorrect.

It is evident that the debate between creationists and scientists will continue for some time, as both sides are bent on proving themselves right. We can clearly see, however, that creationists are using a flawed argument. By using outdated models, their theories are rendered irrelevant. If they are to prove that Earth is indeed only thousands of years old, they will need to analyze the fluctuations of the magnetic field from a new perspective. Likewise, scientists will need to continue their research of the dynamo model until the mysterious energy source is identified. If they can discern the source, they will move one step closer to verifying their model; if they cannot identify it, they will need to turn to other models for answers. The answers for both parties lie in continued research - only then will we be able to determine if we are able to date the Earth using its magnetic field as a clock.

  1. Humphreys, Russell. 1993. "The Earth's Magnetic Field is Young." Impact. Accessed: Oct 15, 2005.
  2. Matson, Dave. 2002. "Young-earth "proof" #11: Since the earth's magnetic field is decaying at an exponential rate, its strength would have been unrealistically high 25,000 years ago. Thus, Earth is less than 25,000 years old." /youngearth/specific_arguments/magnetic_field.html. Accessed: Oct. 15, 2005.
  3. Sarfati, Jonathan. 1998. "The earth's magnetic field: evidence that the earth is young" Answers in Genesis. Accessed: Oct 15, 2005.
  4. Stassin, Chris. 2005. "The Age of the Earth." The Talk.Origins Archive. Accessed: Oct. 31, 2005.
  5. Thompson, Tim. 1997. "On Creation Science and the Alleged Decay of the Earth's Magnetic Field" Talk Origins. Accessed: Oct 15, 2005.