Research output per year
Research output per year
The Earth’s magnetic (geomagnetic) field is generated from deep inside the Earth’s core, but we can still see the effects of it on the surface (e.g.- navigating using a compass) and even benefit from it as it provides a barrier to stop harmful energetic charged particles from space entering into Earth’s atmosphere. However, in recent years the magnetic field has been getting weaker, especially around the South Atlantic region, known as the South Atlantic Anomaly. This has started to cause some issues as energetic particles in this region are now able to reach and interfere with objects in low-orbit around the Earth, e.g.- causing damage to satellites.
In order to fully understand the South Atlantic Anomaly, more measurements of the geomagnetic field are needed to reconstruct how it has evolved through time. Before satellite measurements and historical records (which are available for the past four centuries), it is still possible to get geomagnetic field measurements from signals recorded by the magnetic minerals in archaeological artefacts and volcanic rocks. However, our current databases lack records in the Southern Hemisphere, and also lack older measurements from time periods before 0 AD. This project has collected additional geomagnetic field data over archaeological times from the Southern Hemisphere, from both southern Africa and New Zealand. Additionally, the first geomagnetic field strength measurements for the Neolithic period in the United Kingdom (which occurred between 6000 to 4000 years ago) have been determined.
In addition to providing information about geomagnetic field evolution, geomagnetic field models constructed using sufficient measurement data can also be used to date archaeological artefacts and volcanic rocks of unknown age. The magnetic field recording extracted experimentally from the object under investigation can be matched to an appropriate model in order to tell us the age of said object. This project has shown it is possible to refine an object’s age, even in areas where there are very few geomagnetic field measurements, thus providing valuable information, especially to archaeological excavations in the Southern Hemisphere.
|Effective start/end date
|2017/01/09 → 2023/05/26
Research output: Thesis › Doctoral Thesis (compilation)
Research output: Contribution to journal › Article › peer-review