al_be_erosion_many.m

Syntax:

retstr = al_be_erosion_many(ins)

This function is essentially the same as al_be_erosion_one.m, with the exception that the input structure has only one field, the text string which the user pasted into the text input block in the multiple-sample input form. Thus, the input data checking and parsing routines are slightly different.

The formatting rules for entering a text block containing data for multiple samples are as follows:

1. Enter plain ASCII text only.
2. Each sample should occupy its own line.
3. Each line should have twelve elements, as described below.
4. Elements should be separated from each other by white space (spaces or tabs).
5. Something other than white space must be entered for each element. For example, if you have no $^{26}$Al measurements for a sample, you must enter `0' in the $^{26}$Al concentration and $^{26}$Al uncertainty positions.

In most cases, pasting directly from an Excel spreadsheet should satisfy the rules. An example of an acceptable input text block appears below. The thirteen elements are as follows. These are the same as the input parameters on the single-sample form.

1. Sample name. Any text string not exceeding 24 characters. Sample names may not contain white space or any characters that could be interpreted as delimiters or escape characters, e.g., slashes of both directions, commas, quotes, colons, etc. Stick to letters, numbers, and dashes.
2. Latitude. Decimal degrees.
3. Longitude. Decimal degrees.
4. Elevation/pressure. Meters or hPa, respectively, depending on selection below.
5. Elevation/pressure flag. Specifies how to treat the elevation/pressure value. This is a three-letter text string. If you have supplied elevations in meters and the standard atmosphere is applicable at your site (locations outside Antarctica), enter `std' here. If you have supplied elevations in meters and your site is in Antarctica, enter `ant' here. If you have entered pressure in hPa, enter `pre' here. Any text other than these three options will be rejected.
6. Sample thickness. Centimeters.
7. Sample density. g $\cdot$ cm$^{-3}$.
8. Shielding correction. Samples with no topographic shielding, enter 1. For shielded sites, enter a number between 0 and 1. The shielding correction can be calculated using skyline.m.
9. $^{10}$Be concentration. Atoms $\cdot$ g$^{-1}$. Standard or scientific notation.
10. Uncertainty in $^{10}$Be concentration. Atoms $\cdot$ g$^{-1}$. Standard or scientific notation.
11. $^{26}$Al concentration. Atoms $\cdot$ g$^{-1}$. Standard or scientific notation.
12. Uncertainty in $^{26}$Al concentration. Atoms $\cdot$ g$^{-1}$. Standard or scientific notation.

Here is an example of an acceptable input text block:

FV-TOP-1 38.6139 -109.1878 2527 std 2 2.5 1 4.59e5 1.3e4 2.69e6 8.80e4
FV-TOP-2 38.6136 -109.1955 2580 std 2 2.5 1 202000 8000 1100000 49000
FV-TOP-3 38.6204 -109.2062 2592 std 2 2.5 1 1.02e6 2.60e4 6.05e6 1.31e5
O4-AV-PIT9-NEW -77.8282 160.9762 1300 ant 2 1.9 0.973 6710000 116000 0 0

As with al_be_erosion_one.m, the only calculation that takes place inside this function is the calculation of the uncertainty in the $^{26}$Al $^{10}$Be ratio. Denote the $^{26}$Al/$^{10}$Be ratio by $R_{26/10}$ and its $1\sigma$ uncertainty by $\sigma R_{26/10}$. Assuming linear, uncorrelated uncertainties:

$$\left( \sigma R_{26/10} \right) ^{2} = \left(\frac{\sigma N_{26}}{N_{10}} \right)^{2} + \sigma N_{10}^2 \left( \frac{-N_{26}}{N_{10}^2} \right)^{2}$$ (4)

where $N_{i}$ is the concentration of nuclide $i$ and $\sigma N_{i}$ is its $1\sigma$ analytical uncertainty.