Geology U Th Disequilibrium Age Calculator
U–Th disequilibrium inversion of independently solved matching initialU234/detritalTh/decay closed-system candidate activity curve, all roots retained; no secular-equilibrium shortcut. Caller independently establishes matching units, evidence, method edition and applicability; output is not compliance, diagnosis, work-safety approval, geological identity or validated hazard prediction.
Description
An activity-ratio age interpretation depends on a specified uranium–thorium evolution curve.
An activity-ratio age interpretation depends on a specified uranium–thorium evolution curve.1
A measured ratio may intersect that curve at several ages, so retaining all intersections is more informative than assuming a unique date. Use this tool to calculate u th disequilibrium age from the supplied measurements and assumptions.
When to use Geology U Th Disequilibrium Age Calculator
Use this tool to calculate u th disequilibrium age from the supplied measurements and assumptions. Establish the measurement units, sampled interval, calibration or model edition and geological assumptions before entering data.
How to use Geology U Th Disequilibrium Age Calculator and understand its results
- Establish the measurement units, sampled interval, calibration or model edition and geological assumptions before entering data.
- Enter callerClosedSystemCandidateAges, callerMatchedTh230U238Activities, observedTh230U238Activity, using the field meanings and rules below, then run the tool.
- Read matchingClosedSystemAges. Interpret the fields using their units, signs and evidence conventions below.
- If input validation fails, correct the reported field and run again. Before applying the result, check reference scope, model assumptions and any missing evidence or placeholder values.
| Input field | Meaning | Value type | Requirement |
|---|---|---|---|
| callerClosedSystemCandidateAges | Caller closed system candidate ages | list of number | Required |
| callerMatchedTh230U238Activities | Caller matched th230 u238 activities | list of number | Required |
| observedTh230U238Activity | Observed th230 u238 activity | number | Required |
Enter at least two aligned finite reference ages and responses, with strictly increasing ages. Compare each response with the observed target. Include exact-equality knots, and interpolate every strict sign-change segment linearly; suppress consecutive duplicate coordinates. Return all matches in age order, including no matches when appropriate. For a flat segment exactly at the target the helper returns its sampled endpoints, not every age in the continuous interval. No uncertainty distribution, decay-curve construction or unique-age choice is provided.
matches=exact target knots plus interpolated sign-change coordinates Use the exact units, boundary rules, ordering and missing-evidence conventions above.
| Output field | Meaning | Value type |
|---|---|---|
| matchingClosedSystemAges | Matching Closed System Ages; follow the units, sign, ordering and evidence convention stated above | list of number |
{
"input": {
"callerClosedSystemCandidateAges": [
0,
1,
2
],
"callerMatchedTh230U238Activities": [
0,
0.5,
0.75
],
"observedTh230U238Activity": 0.625
},
"output": {
"matchingClosedSystemAges": [
1.5
]
}
}Limitations and assumptions
A measured ratio may intersect that curve at several ages, so retaining all intersections is more informative than assuming a unique date. Interpretation depends on the units, sampling scope and exact model described above.
All listed fields require explicit values. Unexpected fields, incorrect types, nonfinite numbers and sparse evidence arrays fail validation; the specific bounds and alignment requirements are stated above. Extremely large inputs or outputs can also be rejected. An input error is distinct from a successful result reporting false, no matches or missing evidence.
Alternative or Complementary methods
Use Geology U Pb Discordia Upper Intercept Calculator for this related task: A discordia line summarizes paired uranium–lead ratio observations in a chosen coordinate system.
Use Geology Re Os Isochron Age Calculator when its separate inputs and assumptions fit the question: A rhenium–osmium isochron estimates an initial ratio and age from paired isotope ratios under a shared-system model.
References
Similar or alternative tools
- Geology U Pb Discordia Upper Intercept Calculator
A discordia line summarizes paired uranium–lead ratio observations in a chosen coordinate system.
- Geology Re Os Isochron Age Calculator
A rhenium–osmium isochron estimates an initial ratio and age from paired isotope ratios under a shared-system model.