geochronology

41130 rows


Description

This table stores geochronologic data. Geochronologic measurements are from geochronologic samples, which are from Analysis Units, which may have a depth and thickness. Geochronologic measurements may be from the same or different Analysis Units as fossils. In the case of faunal excavations, geochronologic samples are typically from the same Analysis Units as the fossils, and there may be multiple geochronologic samples from a single Analysis Unit. In the case of cores used for microfossil analysis, geochronologic samples are often from separate Analysis Units; dated core sections are often thicker than microfossil Analysis Units.

Columns

Column Type Size Nulls Auto Default Children Parents Comments
geochronid serial 10 √ nextval('ndb.seq_geochronology_geochronid'::regclass)
geochroncontrols.geochronid fk_geochroncontrols_geochronologyR
geochronpublications.geochronid fk_geochronpublications_geochronologyC
radiocarbon.geochronid fk_geochrons_geochronidR
specimendates.geochronid sd_gcidR

An arbitrary Geochronologic identification number.
sampleid int4 10 null
samples.sampleid fk_geochronology_samplesC

Sample identification number. Field links to Samples table.
geochrontypeid int4 10 null
geochrontypes.geochrontypeid fk_geochronology_geochrontypesC

Identification number for the type of Geochronologic analysis, e.g. «Carbon-14», «Thermoluminescence». Field links to the GeochronTypes table.
agetypeid int4 10 null
agetypes.agetypeid fk_geochronology_agetypesR

Identification number for the age units, e.g. «Radiocarbon years BP», «Calibrated radiocarbon years BP».
age float8 17,17 √ null

Reported age value of the geochronologic measurement.
errorolder float8 17,17 √ null

The older error limit of the age value. For a date reported with ±1 SD or σ, the ErrorOlder and ErrorYounger values are this value.
erroryounger float8 17,17 √ null

The younger error limit of the age value.
infinite bool 1 null

Is «True» for and infinite or “greater than” geochronologic measurement, otherwise is «False».
delta13c float8 17,17 √ null

The measured or assumed δ13C value for radiocarbon dates, if provided. Radiocarbon dates are assumed to be normalized to δ13C, and if uncorrected and normalized ages are reported, the normalized age should be entered in the database.
labnumber varchar 40 √ null

Lab number for the geochronologic measurement.
materialdated varchar 255 √ null

Material analyzed for a geochronologic measurement.
notes text 2147483647 √ null

Free form notes or comments about the geochronologic measurement.
recdatecreated timestamp 22 timezone('UTC'::text, now())
recdatemodified timestamp 22 null

Indexes

Constraint Name Type Sort Column(s)
geochronology_pkey Primary key Asc geochronid
geoage_idx Performance Asc age
ix_sampleid_geochronology Performance Asc sampleid

Relationships

Close relationships within degrees of separation