aggregatechronologies

4 rows


Description

This table stores metadata for Aggregate Chronologies. An Aggregate Chronology refers to an explicit chronology assigned to a sample Aggregate. The individual Aggregate Samples have ages assigned in the AggregateSampleAges table. An Aggregate Chronology would be used, for example, for a set of packrat middens assigned to an AggregateDataset. The Aggregate Chronology is analogous to the Chronology assigned to samples from a single Collection Unit.
An Aggregate may have more than one Aggregate Chronology, for example one in radiocarbon years and another in calibrated radiocarbon years. One Aggregate Chronology per Age Type may be designated the default, which is the Aggregate Chronology currently preferred by the database stewards.

Columns

Column Type Size Nulls Auto Default Children Parents Comments
aggregatechronid serial 10 nextval('ndb.seq_aggregatechronologies_aggregatechronid'::regclass)
aggregatesampleages.aggregatechronid fk_aggregatesampleages_aggregatechronologiesR

PK: An arbitrary Aggregate Chronology identification number

aggregatedatasetid int4 10 null
aggregatedatasets.aggregatedatasetid fk_aggregatechronologies_aggregatedatasetsC

Dataset to which the Aggregate Chronology applies. Field links to the AggregateDatasets table.

agetypeid int4 10 null
agetypes.agetypeid fk_aggregatechronologies_agetypesC

Age type or units. Field links to the AgeTypes table.

isdefault bool 1 null

Indicates whether the Aggregate Chronology is a default or not. Default status is determined by a Neotoma data steward. Aggregate Datasets may have more than one default Aggregate Chronology, but may have only one default Aggregate Chronology per Age Type.

chronologyname varchar 80 null

Optional name for the Chronology.

ageboundyounger int4 10 null

The younger reliable age bound for the Aggregate Chronology. Younger ages may be assigned to samples, but are not regarded as reliable. If the entire Chronology is considered reliable, AgeBoundYounger is assigned the youngest sample age rounded down to the nearest 10. Thus, for 72 BP, AgeBoundYounger = 70 BP; for -45 BP, AgeBoundYounger = -50 BP.

ageboundolder int4 10 null

The older reliable age bound for the Aggregate Chronology. Ages older than AgeOlderBound may be assigned to samples, but are not regarded as reliable. This situation is particularly true for ages extrapolated beyond the oldest Chron Control. If the entire Chronology is considered reliable, AgeBoundOlder is assigned the oldest sample age rounded up to the nearest 10. Thus, for 12564 BP, AgeBoundOlder is 12570.

notes text 2147483647 null

Free form notes or comments about the Aggregate Chronology.

recdatecreated timestamp 22 timezone('UTC'::text, now())
recdatemodified timestamp 22 null

Indexes

Constraint Name Type Sort Column(s)
aggregatechronologies_pkey Primary key Asc aggregatechronid

Relationships