geologic contacts
  SN:   Plane or irregular surface between two types
        or ages of rock; examples are faults, intrusive
        borders, bedding planes separating distinct
        strata, and unconformities. [Glossary of Geology, 4th ed.]
  BT:   stratigraphic sections
  NT:   unconformities
  RT:   stratigraphy
  UF:   contacts (geologic)

geologic history
  SN:   Record (and inferred reconstruction) of the origin
        and development of the Earth since its formation.
  BT:   Earth characteristics
  NT:   biostratigraphy
        Earth history
        lithostratigraphy
  RT:   geologic time scales
        geology
        paleontology
        paleoseismology
        stratigraphy
  UF:   chronostratigraphy
        geohistory

ecological processes
  SN:   Dynamic biogeochemical interactions that occur
        among and between biotic and abiotic components
        of the biosphere.
  BT:   biological and physical processes
  NT:   algal blooms
        bioaccumulation
        biogeochemical cycling
        biological productivity
        contaminant transport
        dispersal (organisms)
        ecological competition
        ecosystem functions
        eutrophication
        extinction and extirpation
        habitat alteration
        migration (organisms)
        pollination
        succession (biological)
  RT:   ecology
        population and community ecology
  UF:   environmental processes
  UF+:  ecological models