MagNetZ with Dave Heslop (2021/08/11) - Simple Uncertainty Propagation For Paleomagnetic Data
Channel: MagNetZ
Date: 2021-08-11

Simple Uncertainty Propagation For New And Legacy Paleomagnetic Data 

The video is also available for download at: https://earthref.org/ERDA/2480/
and can be referenced with the doi: 10.7288/V4/ERDA/2480

Title: Simple Uncertainty Propagation For New And Legacy Paleomagnetic Data
Author: Dave Heslop from the Australian National University, Australia
Author Website: https://earthsciences.anu.edu.au/people/academics/dr-david-heslop

Estimation of paleomagnetic directions plays a crucial role in archeomagnetism, magnetostratigaphy, paleogeographic reconstruction, and constraining past geomagnetic field behavior. While analysis and aggregation of paleomagnetic directional data is performed in a hierarchical fashion, the standard statistical framework employed by paleomagnetists does not consider uncertainty propagation through each level of the hierarchy (i.e., uncertainty of specimen-level principal component analysis, site mean, pole, etc.). With this limitation, inferences drawn from paleomagnetic data will be affected by underestimated uncertainties. I will present an approximate directional uncertainty propagation scheme that applies to Fisher distributions and, thus, to a number of paleomagnetic data processing tasks. The uncertainty propagation scheme is a straightforward addition to the existing statistical framework used to aggregate paleomagnetic directions. Importantly, this scheme can be applied readily to legacy data, even when sample-level demagnetization records are not available. Using illustrative case studies, I will show how uncertainties can be propagated through different stages of the paleomagnetic data processing chain. Finally, I will discuss the limitations of assuming that paleomagnetic directions are Fisher distributed.