A groundbreaking study, published in Nature Geoscience, has revealed the existence of two massive blobs of superheated rock deep beneath Earth’s surface, influencing the planet’s magnetic field. These enormous structures, encircled by a cooler ring of rock, have been affecting Earth’s internal dynamics for millions of years.
The research, conducted by scientists at the University of Liverpool, examines these large blobs of solid, intensely hot rock located in the Earth’s mantle. Surrounded by cooler rock, the blobs play a crucial role in shaping the movement of material within the planet’s interior. The study offers a fresh perspective on Earth’s magnetic field, which has long been a subject of fascination and mystery for geophysicists.
Hot Blobs: Agents of Earth’s Heat
According to the study, the hot blobs are massive regions of superheated rock deep in the Earth’s mantle, far below the surface. These blobs are significantly larger than previously understood and are surrounded by a layer of cooler rock, creating a unique thermal structure within the planet. Scientists believe these zones are not static, but instead interact with the surrounding mantle, driving the movement of material within the Earth’s interior. This motion is essential for processes such as the generation of Earth’s magnetic field.
Variation of earth’s magnetic field across geological periods. Credit: Nature Geoscience
The blobs’ heat influences the surrounding material, affecting the flow of molten rock beneath the Earth’s crust. The movement of this material plays a key role in tectonic plate dynamics and volcanic activity. As the mantle material flows, it contributes to the shifting of tectonic plates, which are responsible for earthquakes and volcanic eruptions. The blobs are thought to be a primary factor in these processes, adding a new layer of complexity to how scientists understand the planet’s internal heat mechanisms.
The Blobs’ Magnetic Power Unveiled
One of the most significant aspects of this discovery is the impact these hot blobs have on Earth’s magnetic field. The magnetic field, which shields Earth from harmful solar radiation and helps maintain a stable climate, has long been understood to be generated by the movement of molten metal in Earth’s outer core. However, as explained in the research, they in the mantle may also contribute to fluctuations in the magnetic field.
The graphs show magnetic latitude and longitude data for two different periods (THOM1-3 and THOM1-12). Credit: Nature Geoscience
The presence of these superheated regions could explain some of the irregularities in the strength and behavior of the magnetic field. Researchers believe the chunks could cause disturbances in the movement of material in the mantle, which, in turn, affects the movement of molten metal in the core. These changes in the flow of material can have a direct impact on the magnetic field, leading to variations in its strength over time.
The Geological Force You Didn’t Know About!
The blobs are believed to regulate the flow of heat between the Earth’s core and mantle, which affects the cooling rate of the planet’s surface. By controlling this heat flow, the clusters help drive important geological processes that shape the Earth’s surface.
“Gaining such insights into the deep Earth on very long timescales strengthens the case for using records of the ancient magnetic field to understand both the dynamic evolution of the deep Earth and its more stable properties,” said Andy Biggin, Prof. of Geomagnetism at the University of Liverpool.
Scientists suggest that the heat from these blobs could contribute to the creation of such hotspots, which are responsible for some of the most active and explosive volcanoes on Earth. This finding could lead to improved models of volcanic behavior and better predictions of future eruptions.