Question

what is the paleo Mars remnant magnetic field?

Answer 1

The existence or record of palaeoenvironments of the magnetic field of the planet (Mars) can be traced by the study of remanent magnetism in the rocks of the planets.

Remanet Magnetism (Magnetization): It is the Magnetism acquired by the rock at the time of the occurrence of the rock on the planet in the direction of the planets magnetic field. The presence of magnetic minerals in the rock (iron, titanium, etc.) are responsible for the presence of magnetism of the rock. This Remanent magnetization is of different types due to their origin of the evolution of rock on the planet's surface. They are:

1). Natural Remanent Magnetization (NRM): is the permanent magnetism in sediments and crystallized magmas

2). Thermal Remanent Magnetization(TRM): magnetism acquired by the rock at the time of colling of lava on the surface

3). Detrital Remanent Magnetization(DRM): magnetism acquired in the sedimentary deposits

4). Chemical Remanent Magnetization(CRM): magnetism acquired due to chemical processes

5). Isothermal Remanent Magnetization(IsRM): remanence magnetism acquired at a fixed temperature

The presence of magnetism in the planet is described using the core dynamo theory.

For Mars, there is no observed magnetic field on the planet today. but some observations i.e. NRM/IsRM ratio tells there might be some significant magnetic field in the past (presence of palaeomagnetism).