rock magnetism
Quick Summary
Rock magnetism is the study of the magnetic properties of rocks, which arise from the magnetic properties of their constituent mineral grains. Typically, only a small fraction of a rock contains magnetic minerals, but this portion dictates the rock's overall magnetic characteristics.12
Key aspects include:
* Types of Magnetization: Rocks exhibit various magnetic behaviors, such as diamagnetism, paramagnetism, ferromagnetism, antiferromagnetism, ferrimagnetism, and superparamagnetism.2
* Remanent Magnetism: This is the permanent magnetism in rocks, formed by the Earth's magnetic field orientation during rock formation. It's crucial for paleomagnetic studies, helping reconstruct past continental movements.3
* Applications: Understanding rock magnetism aids in prospecting for natural resources, dating rocks, and reconstructing Earth's geological history, including continental drift and seafloor spreading. It also has applications in materials science for creating magnetic devices.1
Ask Britannica AI about this topic
Britannica doesn't have a full article on this topic, so we've curated a list of our relevant coverage.
geomagnetic fieldReversals of the main field…component is captured in cooling rocks. Rocks formed at the magnetic equator, for example, contain a horizontal magnetization. Similarly, rocks formed at higher magnetic latitudes contain a field pointing up or down at an inclination that depends on latitude. The declination of the magnetization further reveals the direction to the…
Read More…component is captured in cooling rocks. Rocks formed at the magnetic equator, for example, contain a horizontal magnetization. Similarly, rocks formed at higher magnetic latitudes contain a field pointing up or down at an inclination that depends on latitude. The declination of the magnetization further reveals the direction to the…
Read More
Tertiary PeriodCorrelation of Tertiary strata…pick up and retain the magnetic orientation of the field at the time they are formed through either sedimentary or igneous processes. With the development of techniques for measuring the rock’s original orientation of magnetization, a sequence of polarity reversals has been dated for the late Neogene. In addition, a…
Read More…pick up and retain the magnetic orientation of the field at the time they are formed through either sedimentary or igneous processes. With the development of techniques for measuring the rock’s original orientation of magnetization, a sequence of polarity reversals has been dated for the late Neogene. In addition, a…
Read More
