Data from the Paleomagnetism .col format can be imported to the statistics portal. Each selected file and group will be associated with a new selectable collection. An alternative example of the default input file can be found here.
Figures showing the selected collections and their geomagnetic directions & distribution of virtual geomagnetic poles. The right figure does not show actual VGP positions. The table lists standard Fisher parameters for this set of directions. When multiple collections are selected, its components will be combined before a cutoff is applied. Press 8 and 5 to switch between coordinate frames and confidence ellipses respectively. Below you'll find an inclination-only statistics table.
Note: The illustrated VGP distribution and cutoff is relative to the mean and does not show true VGP positions. All directions are assumed to come from the same geographic location.
Inclination-Only statistics
Paleomagnetic directions record declinations and inclinations. In some cases, due to structural problems or lost azimuths in drill cores, only the inclinations are reliable. The arithmetic mean for inclination-only data is biased towards shallow inclinations In this table you can check the differences between the arithmetic mean and inverse variance and the Arason and Levi, 2010 Maximum Likelihood Method that estimates κ and α95.
Figures showing the mean direction of the mean of all selected collections seperately. Press 8 and 5 to switch between coordinate frames and confidence ellipses respectively. The selected cutoff is applied to each collection.
Select two collections and click initialize to begin the bootstrap. (A) Tauxe et al., 2010 CTMD test. Overlapping distributions indicidate that two collections are the same within confidence limits. (B) CMDT from Heslop et al., 2023, showing the histogram of λ(b)min. If CMTD value is less than the critical value directions are not different.
This module allows the user to do a classical foldtest (Tauxe & Watson, 1994) and an inclination only tilt test (Enkin & Watson, 1996) on one or multiple collections. No cutoff will be applied. Select any number of collections and click initialize to start.
Bootstrap Foldtest
Bootrstrap Inclination-Only foldtest
Pick between Inverse variance and Arason-Levi's κ
The inclination shallowing module unflattens observed inclinations in sediments to fit with the TK03.GAD Field Model (Tauxe et al., 2008) based on the relationship between the expected elongation (E) (τ2/τ3) and inclination. The flattening function of (King, 1955) is applied. A single collection can be selected and a cutoff will be applied. A minimum of 80 directions are required. The procedure can be bootstrapped 1000 times to find its confidence limits.
A pole-cutoff can be selected that will be applied to the polar distribution.
| Cycle Confidence Ellipse (α95, A95) | Cycle Coordinates | Save Selected Collections | Remove Selected Collections | Copy selected collection to clipboard | 5 | 8 | s | q | e |
Note: metadata is applied to all components in collection. To assign more metadata to each component choose an alternative input method.
A new collection can be saved from the currently combined selection. Rejected components can be discarded and all components can be reversed.