This table is used to provide more information for age dates of geologic materials referenced in various other feature classes. If need be, these dates could be linked to a more comprehensive geochronology data model that contains analytical data and discussion.
| Field Name | Field Alias | Length (text fields) |
Field Type | Field Value | Default | Allow Nulls? | Attributes / Examples | Description / Notes |
|---|---|---|---|---|---|---|---|---|
| SampleID | " | 50 | String | variable | undefined | TRUE | ER-09-123 | ID of sample dated |
| GeoID | " | 20 | String | variable | [null] | TRUE | Tb | ID of rock unit sampled (related to lithology detail) |
| IsoAge | IsotopicAge | Double | variable | [null] | TRUE | 23.245 | Isotopic age | |
| AgeError | " | Double | variable | [null] | TRUE | 0.0123 | Isotopic age error | |
| TimeUnits | " | 20 | String | variable | [null] | TRUE | Ma, Ga, ka, yr BP, C-14 years | Units of time |
| DateMethod | " | 50 | String | variable | [null] | TRUE | Ar-Ar, U-Pb, U-series, Rb-Sr, C-14, cosmogenic, paleontology, etc. | Method of dating |
| Material | " | 255 | String | variable | [null] | TRUE | sanadine, K-spar, zircon, muscovite, monazite, Calcite, etc. | Material dated |
| Technique | " | 255 | String | variable | [null] | TRUE | single crystal, total fusion, whole rock, U-Pb isochron, U-series, etc. | Technique of dating |
| RockType | " | 128 | String | variable | CVD | TRUE | plutonic, volcanic, sedimentary, metamorphic | Rock type of sample |
| RockDesc | " | 255 | String | variable | [null] | TRUE | Brief description of the rock | Description of sample |
| Interp | Interpretation | 255 | String | variable | [null] | TRUE | cooling age, crystallization age, etc. | What the age means with respect to the sample. |
| NumSamples | " | Short Integer | variable | [null] | TRUE | number of independent analyses used to compute date | Number of samples | |
| ProvnclAge | ProvincialAge | 255 | String | variable | [null] | TRUE | Blancan, Osagean, Santonian | Provincial age |
| SourceID | " | 128 | String | variable | [null] | unknown; unspecified; Smith, 2006b [variable] | Feature level metadata (who mapped this); related to bibliographic detail | |
| Report | " | 128 | String | variable | [null] | TRUE | link to analytic data (e.g. internal reports) | Report ID |
| ReportDate | " | date | variable | [null] | TRUE | Date report/reference was released/published | Report date | |
| Comments | " | 255 | String | variable | [null] | TRUE | Comments about this particular date. |