Rabat – Rocks can tell us stories of events that occurred billions of years ago, giving us insight into the very core of our Earth. It is through rocks that scientists can determine approximately how old our Earth is, explain the movement and shifts of our ancient continents, identify the direction through which Earth moves, and calculate the sheer strength of its magnitude.
The archaic rocks of our Earth often act as a compass for geologists, unravelling layers of information about our Earth.
What is a geological magnetic anomaly?
Our Earth can be divided into three layers: the core, the mantle and the crust. Its core consists of an inner solid core and the outer liquid core. The liquid outer core of the Earth is what generates the Earth’s magnetic field, which is controlled by the north and south poles of the Earth. The core powers the Earth’s magnetic activity, which in turn, affects the entire layout of landmasses — which shift and move.
These shifts and flips in magnetic activity are recorded in rocks and can help scientists determine what this activity looked like millions of years ago; scientists have agree for years that this activity was generally unstable.
Magnetic anomalies, according to the United States Geological Survey (USGS), are deviations in the Earth’s magnetic field caused by variations in the magnetisation of rocks in the subsurface.”
550 million years ago, one of these anomalies was a real head-scratcher for many scientists for so long. The Ediacaran era showed signs of anomalies in rocks, suggesting bizarre and wild magnetic activity at the time. What, exactly, was this anomaly? How did Earth’s ancient land masses shift and move?
Scientists theorized for decades about what might have caused the unusual paleomagnetic footprints. One leading theory is the true polar wander, which suggests that the shift of the two magnetic poles in relation to the Earth’s crust is what might have caused the apparent anomaly.
However, with the help of the Atlas Mountains and new research from Yale, this theory is contradicted.
The Atlas Mountains help solve the anomaly
Through a study led by Yale University in mid-October, researchers collected Ediacaran-era rocks from the High Atlas Mountains of Morocco. The geological excursion initiated by Yale University suggests, through the results of the study of the sampled rocks, that there is “a new model for the Earth’s magnetic field that finds structure in its variability rather than simply dismissing it as randomly chaotic,” says geologist David Evans of Yale University.
The study concluded that the magnetic field at the core of the Earth’s magnetic field would often experience variability during that time — the supposed ‘chaos’ of the Earth’s activity at the time actually had an underlying pattern, although it was a complex one. The researchers called it the “ordered variability,” and used a mathematical formula to find that the Earth’s poles had a consistent, circular pattern rather than sporadic shifts.
The rocks collected in the High Atlas Mountains have helped solve a mystery that many researchers have been working on for decades. The discovery has completely revolutionized the science of geology as it provides more accurate insights into how the Earth’s magnetic field used to operate.
Numerous paleomagnetic studies over the Ediacaran era have been conducted. Due to the variety in the geological prints of the era, the data have been subject to different interpretations by different scientists.
The excavated rocks from the High Atlas Mountains of Morocco provide a fascinating and comprehensive capsule of this era and its magnetic activity. The preserved and stratified rocks allowed scientists to conduct the most comprehensive study yet related to the Ediacaran era.
David Evans, director of the Yale Paleomagnetic Laboratory, has expressed that if their new statistics and data prove to be more accurate, it could represent a new era in Geology and paleontology, as scientists would be able to bridge between the earliest and latest rocks formed in our earth.
