Dating Methods
absolute dating
age equivalence
allostratigraphy
period - all
mode - a mappable stratiform body of
sedimentary rock defined
and identified on the basis of bounding
discontinuities
measures - alluvial and lacustrine deposits
in a graben, physical
records of glaciations, discontinuous
terrace deposits
aluminum-26
mode - cosmogenic in situ exposure
accumulation
measures - desert glass histories of
exposure, growth rate of
manganese nodule, faulting slip rates
alunite
method - alunite accumulation on the cave's
walls
measures - rainfall histories, tectonic
uplift , age of cavities
amino acid racemization
period -
asparagine - 0-25000 bp
isoleucine - 5000-2 m. bp
mode - when the organism dies, control
ceases, and the ratio of
D/L moves slowly toward equilibrium
(racemic)
measure - desert varnish, proteins,
tissues, age, bones, shells,
sediments, authenticity
synonyms - ostrich eggshell dating,
L-amino/D-amino ratio
annually laminated sediments
- see varve chronology
aragonite/calcite ratios
measures - relative accuracy of the
hydrograph
archaeology
period - 0-50000 bp
archaeomagnetic dating - see
paleomagnetic dating
archaeometry
Argon-37
mode - produced from decay of calcium-40,
half-life is 35 days
measures - atmospheric circulation
Argon-39
period -
mode - atmospheric 39Ar is produced by
cosmic ray activity,
half-life falls between that of 3H and
14C
measures - isolation ages of deep and
bottom waters, ice coring
applications, ground water dating,
hydrologic studies, ocean
water circulation and mixing
argon-40/argon-39
period - 2000 - 3400 m. bp
mode - irradiated potassium-40 changes to
argon-39 allowing exact
ratio of potassium-40 to argon-40 which
is related to time
passed since formation
measures - volcanic rock, lunar highland
meteorite impact melt
clasts, landscape evolution, uplift
history, tephra, marine
sequences, pumice, tuff, sanidine,
trap activity, muscovite,
orogenic development, exhumation,
K-feldspar, metamorphic
rocks, thermal history,
morphotectonics, lavas, basalts,
tektites, andesites, mica, feldspar,
hornblende, boninitic
pillows, pyroxenes, biotite,
plagioclase, adularia, gabbro,
sericite, celadonite, meteorites, batholiths,
dykes, schists,
tourmaline, amphibole
synonyms - thermochronometry, Ar
thermochronometry,
40Ar/39Ar thermochronology,
geothermometry
40Ar/39Ar geochronology - see geochronology
40Ar/39Ar thermochronology -
see argon-40/argon-39
Ar thermochronometry - see
argon-40/argon-39
artifact time marker
mode - an artifact type that was made by a
particular culture
during a limited time period, an
indication of at least the
relative time of the occupation
synonyms - index types
astrochronology
astronomical dating
period - 0 - 4000
mode - astronomical consistencies change
over time, compares
current to past changes in the angle of
the ecliptic, heliacal rising
of Sirius, last sighting of the Lunar
crescent each month
measures - astronomical artifacts,
Astronomical Polarity Time
Scale - see cyclostratigraphy,
paleomagnetic dating
Astronomical time scale (ATS)
10Be/9Be
period -
0 – 50000 bp
mode - cosmogenic 10 Be production,
10Be/9Be ratio
measures - sediments, ice/rainwater, desert
glass histories of
exposure, temporal variations in ice,
deposition rates, growth
rate of manganese nodule, faulting slip
rates
synonyms - beryllium dating
beryllium dating - see
10Be/9Be
biostratigraphy
period - recent to Cambrian
mode - dating by association with index
fossils, provides a relative
age, and sometimes a first
approximation to a numerical age, a
body of rock defined and characterized
by its fossil content,
species change,
measures - sediments, terrestrial and
marine palaeoenvironmental
records, tephra, crustal dynamics,
ancient environments of
deposition
synonyms - fossil reconstruction, index
fossil
Calcium 40
mode - potassium-40 decays into the gas
argon-40 and
calcium-40 at a known rate
Calcium 41 dating
mode - AMS of 41Ca
measures - bone
synonyms - radiocalcium dating, 41Ca,
calcium isotope dating
calcium/potassium leaching
Carbon 14 dating - see
radiocarbon dating
carbon isotope
measures - water
cation ratio dating
mode - rock varnish of rock carvings vs
uncarved
measures - rock carvings, petroglyphs
Cesium137
period -
0 - 10000 bp
mode - short-lived isotope
measures - sediment accumulation rates and
patterns, soil
erosion, radioactive fallout, deposit age
chemical isotope dating - see
isotope analysis
chemical transformations
mode - molecular changes over time
measures - food residue, chemical residues
Chlorine 36
measures - polar ice, nuclear industry
pollution, hydrogeology,
ice, groundwater
synonyms - radiochlorine, 36Cl , chlorine
isotope dating
Chlorine 39
chronometric dating
chronostratigraphy
period - recent to Cambrian
mode - provides a means of organizing
strata into units based on
their age relations. A
chronostratigraphic unit is a body of rock
established to serve as the material
reference for all rocks
formed during the same span of time.
measures - eonothem, erathem, system,
series, stage, and
chronozone,
synonyms - Standard Global
Chronostratigraphic Scale
climatic time series - see
cyclostratigraphy
climatostratigraphy
measures - glacial events
content comparison - see
image dating
contextual placement - see
image dating
coral dating
mode - annual coral rings or bands
measures - climate change
cosmochronology - see
cosmological time scale
cosmogenic dating
mode - dating how long the surface of a rock
has been exposed
to cosmic rays coming in through the earth’s
atmosphere
measures - surface exposure age, model
erosion rates, meteorites,
terrestrial rocks, plagioclase, uplift
rates, exhumation rates, lava
flows and dams, olivine crystals within
basalt, denudation
synonyms - cosmogenic 3He dating,
cosmogenic isotope analysis
cosmogenic 3He dating - see
cosmogenic dating, 4He/3He
Thermochronometry
cosmogenic isotope analysis -
see cosmogenic dating
cosmological time scale
synonyms - cosmochronology
cross-dating
cultural affiliation dating
cyclicity - see
cyclostratigraphy
cyclostratigraphy
period - 0-500 m. bp
mode - spectral analysis measures
periodicities of precession,
obliquity and eccentricity, changes in
climate induced by the
astronomical variations of the Earth's
orbit
measures - sediments, clays
synonyms - cyclicity, orbital forcing,
climatic time series,
Astronomical Polarity Time Scale
Dansgaard-Oeschger Events
mode - 10-15 kyr long bundles of rapid (ca.
1 kyr long) warm-cold
oscillations
measures - stadials and cold rebounds
deglaciation chronology
measures - uplift rates, glaciers and sea
level fluctuations
dendrochronology
period - 0-12000 bp, floating sequences
back as far
as the Cretaceous Period
mode - annual rings are produced in the
xylem of trees grown in
latitudes where extremes in
temperature occur
measure - wood, rainfall, drought, heat
waves, cold spells, climate,
ecosystem health, pollution of air,
soil, or water, volcanic and
meteoric impact events, forest
histories, solar sunspot activity,
authenticity
synonyms - tree ring analysis, tree ring
dating
denudation chronology - see
geochronology
derivative dating
desert varnish
mode - the condition of extreme dryness
and intense solar
radiation affecting artifacts
measures - artifacts, rock art
Detrital thermochronometry -
see thermochronometry
diatom dating
measures - palaeoenvironmental
reconstructions,
palaeoecologies
differential weathering
mode - relative weathering indicates age
or priority
measures - rock art
DNA analysis
period - 0-300,000 bp
measures - tissue samples, insects
preserved in amber, ostrich
eggshells, bones, Neanderthal, teeth,
collagen, hair, bacteria,
fungi, yeasts, mummification
processes, effects of diets,
origins and spread of agriculture,
domestication, migrations,
lineages, genealogical structure,
population size, mutation
rates, gene mapping
eggshell dating - see ostrich
eggshell dating
electron spin resonance
period - 500 - 500 million bp
mode - background radiation causes electrons
to dislodge
from their normal positions in atoms and
become trapped in
the crystalline lattice of the material,
subjected to
electromagnetic radiation in a magnetic
field causes
electrons to resonate and absorb
electromagnetic power. The
strength of resonance reflects the
number of electrons that
have become trapped since the crystals
were formed.
measures - dates mineralization,
sedimentation, last heating
of minerals, coral, bones, teeth,
shell, calcium carbonate in
limestone, quartz, flint, meteorite
strikes, earthquake activity,
calcite, tooth enamel, volcanic ash,
feldspar, pumice
synonyms - ESR
erosive change
synonyms - microwear analysis
ESR - see electron spin
resonance
event stratigraphy
measures - flood, tephra deposits, lake and
loess sediments, local,
regional and global climate conditions
synonyms - natural catastrophe stratigraphy
excess (226)Ra - see
238U-230Th-226Ra
fission track dating
period - 20 to 6 b. bp
mode - damage trails produced by
spontanaeous splitting of a
radioactive atom in glassy materials,
reflects the time passed
since last exposed to high
temperatures
measure - apatite, zircon, sphene,
titanite, biotite, mica, barite,
epidote, garnet, natural glasses
including obsidian,
pitchstone, tephras, man-made
ceramics, temperature
history, last firing, rates of uplift
and exhumation, sediment
sourcing, meteorites, sea floor
spreading rates, volcanic arc
motion
synonyms - fission track thermochronology
fission track geochronology -
see geochronology
fission track thermochronology
- see fission track dating,
thermochronometry
fluorine analysis - see
U-Fl-N dating
fluorine, uranium and
nitrogen test - see U-Fl-N dating
foraminifera
period - recent to eocene
mode - profiles
measures - sediments, tuffaceous sediments
forensics
measures - ceramics and cores of cast
metalwork, wooden
artifact, time of death, age estimation,
forgeries, authenticity
fossil reconstruction - see
biostratigraphy
gene mapping
geochemical dating
geochronologic scales - see
geochronology
geochronology
period - recent to Precambrian
mode - A geochronologic unit is a division
of time distinguished
on the basis of the rock record
preserved in a
chronostratigraphic unit. the science
of determining the age of
rocks, fossils, and sediments
measures - advance and retreat of glaciers,
sea level fluctuations,
land-uplift, denudation, tephra,
fossil zonations,
radioactive-decay rates, eon, era,
period, epoch,
age, and chron, plate reconstructions,
lava flows
synonyms - land-uplift chronology, fission
track geochronology,
denudation chronology, geochronologic
scales, 40Ar/39Ar
geochronology, K–Ar geochronology, U–Pb geochronology,
plutonic geochronology, geologic time
scale
geochronometry
period - all
mode - A geochronometric (or chronometric)
unit is an
isochronous direct division of geologic
time expressed in
years (Article 96). It has no material
referent.
geologic chronology - see
geologic time scale
geologic time scale
mode - vertical succession of sedimentary
rocks and structures
were used to date geologic units and
events relatively.
synonyms - geochronology, geologic
chronology,
geomagnetic polarity time
scale - see geomagnetic reversal time
scale, paleomagnetic dating
geomagnetic reversal time
scale
synonyms - geomagnetic polarity time scale,
GRTS
geomorphology
measures - paleoclimates, glaciations,
soils, tectonics, landforms,
settlement responses, environmental
changes, periglacial
and fluvial landforms and deposits
geothermometry - see
argon-40/argon-39
GISP2 ice core - see ice core
dating
GISP2 isotope record - see
ice core dating
glacial geomorphology
synonyms - glacial geology
global climatic event
measures - traps emissions,
Dansgaard-Oeschger cycles, Heinrich
events
GRIP ice core - see ice core
dating
growth change
synonyms - age/maturity analysis
GRTS - see geomagnetic
reversal time scale, paleomagnetic dating
3H dating - see tritium
analysis
hafnium-tungsten dating
4He/3He thermochronometry
mode - buildup of 3He indicates amount of time that the rocks
have been exposed.
measures - olivine crystals within basalt,
fault motion
synonyms - thermochronometry, cosmogenic
3He dating,
radiogenic helium
Heinrich events
period - quaternary
mode - massive discharges of icebergs
measures - stadials and cold rebounds,
sediment, moraine
sequences, climatic events
helium-lead dating
measures - detrital zircon,
thermochronology,
hydration profiles
mode - newly exposed surfaces of rock
bearing silicates will take
up water from the atmosphere. The amount
of hydrogen is
directly proportional to the amount of
water in the micro layers
of the rock surface.
synonyms - hydrogen depth profile, obsidian
hydration dating,
quartz hydration dating
hydrogen depth profile - see
hydration profiles
hydrogen isotope
measures - hydrothermal alteration, ore
deposition, water
hydrograph
mode - represents lake levels
ice core dating
period - 0 - 110000 bp
mode - annually laminated coring and
analysis
measures - paleoclimate, 18O/16O, isotopic
events, stadials, cold
rebounds, Dansgaard-Oeschger cycles,
Heinrich events,
solar activity, cosmic-ray flux, CO2
cycle, tephras, sediments,
environmental changes, oxygen
isotopes, palaeotemperatures,
chemical traces of eruptions,
volcanism, prevailing wind
patterns, climatic forcing, meltwater
spikes, cryptotephra,
ice-flow models, local climate record,
volcanic activity,
interstadial correlations,
synonyms - GISP2 ice core, GRIP ice core,
GISP2 isotope record
ice flow models
period - 0- 7500 bp
measures - tephra layers, ice
image dating
mode - comparisons to datable material
measures - images
synonyms - content comparison, contextual
placement, style,
superimposition
immunological
measures - proteins associated with
carbonate or phosphate
minerals, proteins adsorbed to siliceous
minerals
incremental dating
index fossil
mode - association with a species that is
known to have lived only
during a specific time period
synonyms - biostratigraphy
index types - see artifact
time marker
infrared stimulated
luminescence
mode - based on the release of electrons
trapped in crystal defects
measure - quartz, polymineral fine grains,
palaeolimnological
record, catchment disturbance,
lake-sediment records, sands,
deposition bleaching characteristics,
aeolian sand, alluvial fan
deposits, desert sands, potassium
feldspars, alluvial sediments,
loess, sediments, dune sands, sediment
cores, earthquake
recurrence, fault movements, feldspar,
waterlain sediments,
high arctic marine sediments,
plagioclase, organic-rich
sediments, reworked silty sediments,
fault-related sediments,
detrital feldspars, sodium feldspars,
synonyms - luminescence
inter-site patterning
measures - rock art
Iodine-129
measures - hydrogeologic
iodine-xenon dating
mode - neutron-irradiated
measures - meteorites
ionoluminescence - see
luminescence
isotope analysis
mode - variation in common isotopes due to
temperature variation
measures - carbonate, shell, clams,
bivalves, fresh water flow,
water salinity, tephra, uplift,
hotspot, terrace deposits,
continental collisions, geological
processes,
synonyms - isotopic analysis, chemical
isotope dating, isotopic
geochemistry, isotope geology
isotope geology - see isotope
analysis
isotopic geochemistry - see
isotope analysis
isotopic time scale
isotopic stratigraphy
measures - tephra, traps, carbonates,
climatic response to traps
emissions, cooling effect of aerosols,
warming effect of
volcanic C02, global climatic events
40K
measures - authenticity, soils
K-Ar dating - see
potassium-argon dating
K–Ar geochronology - see
geochronology
81Kr
measures - atmospheric abundance
85Kr
measures - hydrology, oceanography,
atmospherics,
environmental studies
L-amino/D-amino ratio - see
amino acid racemization
lake sediment successions -
see varve chronology
laminated sediments - see
varve chronology
land-uplift chronology - see
geochronology
lead-lead dating - see U/Pb
dating
lichen growth analysis - see
lichenometry
lichenometry
period - 10 - 3000 bp
mode - lichen growth depth and extent,
thallus grows
systematically in proportion to age
measures - snow-avalanche activity, time of
surface stabilization,
moraines, glaciation, glacier
fluctuations, glacier advances
synonyms - lichen growth analysis
limnology - see
paleolimnology
lithodemic unit
period - recent to Precambrian
mode - defined body of predominantly
intrusive, highly deformed,
and/or highly metamorphosed rock,
distinguished and delimited
on the basis of rock characteristics,
generally does not conform
to the Law of Superposition, with
mappability
measures - intrusive, highly deformed,
and/or highly
metamorphosed rock, terranes in which
rocks generally lack
primary stratification, lithology, local
and regional structure,
economic resources, and geologic
history, gneiss, diorite,
granite, intrusion, dike, syenite,
volcanic complex, gabbro,
schist, plutonics, extrusives, their
weathering products,
granodiorite, sills,
lithostratigraphy
period - recent to Precambrian
mode - layered rocks and sequences that
obey the Law of
Superposition, unit is a stratum or
body of strata, generally but
not invariably layered, generally but
not invariably tabular,
which conforms to the Law of
Superposition and is
distinguished and delimited on the
basis of lithic characteristics
and stratigraphic position.
measures - sedimentary, extrusive igneous,
metasedimentary, or
metavolcanic strata, clay, gravel,
till, and other unconsolidated
deposits, supergroups, groups,
formations, members, beds, and
flows
loess-chronometry
mode - tephra sandwiched between two master
tephras is afforded
its age by interpolating the thicknesses
of loess between them
measures - tephra
low-temperature
thermochronometry - see (U-Th)/He dating,
thermochronometry
luminescence - see infrared
stimulated luminescence,
ionoluminescence, optical dating,
optically stimulated
luminescence, OSL, pulsed photostimulated
luminescence, PTTL, radioluminescence,
thermoluminescence,
TL
magnetic anomaly time scale
period - 0 - 71 m. bp
measures - tectonic evolution, basalt,
sediments,
synonyms - paleomagnetic dating
magneto(cyclo)stratigraphy
period - 0-500 m. bp
measures - marine and continental
sequences, marine-continental
correlations
synonyms - paleomagnetic dating
magneto-stratigraphy
measures - coastal plain, sediments,
terrestrial and marine
palaeoenvironmental records, traps,
tephra, exhumation,
synonyms - paleomagnetic dating
marine isotope stage (MIS) -
see oxygen isotope
microwear analysis - see
erosive change
migration analysis
measures - settlement, resettlement,
expansions, arrivals
morphostratigraphy
nannofossil stratigraphy
measures - tephra, traps, bentonite,
sediments
natural catastrophe
stratigraphy - see event stratigraphy
Ne-21
mode - cosmogenic
measures - denudation
nitrogen
mode - nitrogen decreases through the decay
of bone protein
measures - bone, recent intrusions
noble-gas thermochronology -
see thermochronometry
18O
period - 0 - 500000 bp
measures - climatic response to traps
emissions, cooling effect of
aerosols, warming effect of volcanic
C02, plankton
synonyms
- radio-oxygen, oxygen isotope, marine isotope stage
(MIS)
18O/16O - see oxygen isotope
obsidian diffusion dating -
see obsidian hydration
obsidian hydration dating
period - 500 - 10000 bp
mode - when obsidian is newly exposed to
the atmosphere, its
surface begins to absorb water from the
air, which gradually
seeps into the interior of the stone,
thickness of this hydration
layer is directly proportional to the
amount of time since the
rock was formed or since a fresh
surface was exposed
measures - obsidian artifacts, flakes,
seismic history, volcanic
glass, glass, temperature, humidity,
glasses used for encasing
waste, industrial glasses, environment,
basaltic glass, silicic
glass
synonyms - obsidian diffusion dating,
hydration dating
optical dating - see luminescence,
optically stimulated luminescence
optically stimulated
luminescence
period - 100 - 500000 bp
mode - light causes electrons of the
mineral atoms to be
progressively dislodged, exposing it
to lasers, which releases
the electrons from the defects,
measures the last time an object
was exposed to sunlight,
measures - human occupation, colonisation,
quartz, alkali
feldspars, sediments, zircon,
feldspars, coversands, aeolian
sediments, dune sands, sedimentary
quartz, shoreline deposits,
silty or sandy water deposited
sediments, unheated sediments,
mineral crystals, fired ceramics,
soils, authenticity, pottery,
clays, art objects, sherds, quartz and
feldspar rich sediments,
burnt flints, sediments from
archaeological sites, calcite,
fimic anthrosol, dune migration,
lateral migration rate of a
meander, sand deposition, agricultural
activity, fluvial deposits,
Al2O3:C, annealed quartz, retrospective
dosimetry, potassium
feldspars, tephra glass, bricks,
micas, mixed silicates, granite,
tsunami-laid sands, glaciofluvial
sediments, buried podsols,
organic-rich sediments, flood deposits,
porcelain, flint,
loess, soil erosion, colluvia,
cultural activities, stone surface,
rhyolites, time of construction and
destruction of a building,
silt
synonyms - optical dating, OSL, pulsed
photostimulated
luminescence
orbital forcing - see
cyclostratigraphy
orbital time scale
OSL - see optically
stimulated luminescence
ostracode assemblages
measures - hydrograph, lake level,
paleoclimate
ostrich eggshell dating - see
amino acid racemization, eggshell
dating
oxidizable carbon ratio
period - 1 - 35000 bp
mode - site-specific rate of biodegradation
of carbonized organic
matter, such as soil humic material or
charcoal found in soil.
ratio of total carbon to readily
oxidizable carbon
measures - soil, cultural features,
abandonment, carbonized
organic matter, soil humic material or
charcoal, biodegredation
of organic carbon, readily oxidizable
carbon, total carbon,
active pedogenic, nonpedogenic
sediments, formerly pedogenic
buried soils (paleosols), aerobic
conditions only, stratified
fluvial deposits, desert pavements,
vessicular soils, glacial
deposits, earthworks, geoglyphs,
middens, pit features,
stratified riverbanks, open-air
surfaces, sub-plowzone sites,
mounds
oxygen isotope
measures - hydrothermal alteration, ore
deposition, water, large
foraminifera, paleoceanography,
sediments, marine terraces and
coastal landforms, sea level, deposits,
breakup of an ice sheet,
high sea level deposits, intervals of
warm temperature, ice cores,
ice volume, lunar highlands meteorite,
shelly material, global
temperatures, ice ages, deep sea
sediments, skeletal material,
climatic variation, tephras,
palaeoenvironmental records,
meltwater spikes, stadials and cold
rebounds, Dansgaard-
Oeschger cycles, petrogenesis, arc
magmas, biogenic silica,
faunas, sedimentary cores, volcanic rocks,
K-feldspar
overgrowths (adularia), volume of the
ocean, thermal history of
shales, arkose, formation depth,
temperature, and salinity
synonyms - marine isotope, 18O, 18O/16O ,
planktic stable
isotope
231Pa/230Th
measures - basalts, marine phosphorites,
ocean sediments
paleobiogeography
paleoceanography
paleogeography
measures - human occupation history,
environmental change,
water basin dynamics, climatic change,
population migration
paleolimnology
period - 300-3 m. bp
measures - fresh-water rather than marine
deposits, environmental
change, catchment disturbance,
lake-sediment
synonyms - limnology
paleomagnetic dating
period -
polar wander path - 0 - 100000 bp
geomagnetic pole reversals - 690000 -
500 m. bp
apparent polar wander paths - back to
Precambrian times
mode - based on comparison between the
current magnetic field
and rock remanent magnetic directions
and intensity
measure - lavas, settled volcanic ash,
loess (wind blown
sediments), detrital sediments in
still ponds and lakes
strongly heated samples found near
igneous events, fireplaces,
kilns, and structural fires
synonyms - archaeomagnetic dating,
magneto-stratigraphy,
magneto(cyclo)stratigraphy, magnetic
anomaly time scale,
GRTS, geomagnetic reversal time
scale, geomagnetic polarity
time scale, Astronomical Polarity
Time Scale
paleontology
Paleontological Time Scale
paleothermometry
period - 0-70,000 bp
mode - reconstructing regional and local
climatic responses to
changing atmospheric conditions
measures - paleotemperatures,
glacial-interglacial cycles, fossil
assemblages collected from loess
sediments, gastropod shells
from loess deposits,
palynology
period - 0 - 400 m. bp
mode - study of vegetation history using
the microfossils (pollen
grain and spores of size 15-50 um)
measures - lake basins, sediments, past
environments, people's
lifestyles, vegetational, floristic and
climatic changes, sea levels,
condition of the forest, wind
direction, vegetation identification
of surrounding areas, pollen traveling
distance, lake
sedimentation, turn-over rate of the
lake ecosystem,
reconstructing ancient climates and
dating soil strata, peat,
gyttja, warm/cold current migrations,
human occupation history,
carbon accumulation rates, mire
ecosystems, deforestation,
upper continental slope, continental
shelf, and coastal plain,
landscape change, peat-bogs,
temperature and rainfall, raised
montane bog, mean temperature of the
coldest month, annual
temperature sum above 5 °C, ratio of
actual to potential
evapotranspiration, relative sea-level
synonyms - pollen profiles
patination
mode - determine the age of artifacts,
relative to others, by
comparing the thickness of the patina
on them
measures - rock art, flint artifact,
bronze, glass, stone artifacts,
synonyms
- relative patination
210Pb
period - 0 - 150 bp
mode - lead isotope produced in the
atmosphere by the
decay of 222Rn
measures - lake and loess sediments, local,
regional and global
climate conditions, aquatic and peat
deposits, sediment
accumulation and soil erosion, marine
sediment, time of
sediment deposition, glacial ice
Pb-alpha activity - see U/Pb
dating
Pb-I
Pb-Pb - see U/Pb dating,
lead-lead dating
pedostratigraphy
period - recent to Precambrian
mode - a body of rock that consists of one
or more pedologic
horizons developed in one or more
lithic units now buried by a
formally defined lithostratigraphic, or
allostratigraphic unit or
units.
measures - buried soils, geosols,
Phanerozoic Time Scale
physical anthropology
measures - DNA patterns, movement of
groups,
pigment dating
mode - known availability
measures - rock paintings, paintings
planktic stable isotope - see
oxygen isotope
plutonic geochronology - see
geochronology
pollen profiles - see
palynology
potassium-argon dating
period - 20000-4.6 b. bp
mode - Potassium-40 undergoes radioactive
decay by electron
capture to Argon-40 which is trapped
in mineral
measure - sea floor spreading rates,
andesite, basalt, biotite,
muscovite, hornblende, volcanic
feldspar, micas, plagioclase,
clays, volcanic glass, igneous rocks,
meteorites, heat treated
projectile point, pottery,
synonyms
- K-Ar dating
prehistoric gene mapping
Prehistoric Time Scale
Protactinium - see U/Th
dating
PTTL
measures - fluorite, quartz
synonyms - luminescence
pulsed photostimulated
luminescence - see optically stimulated
luminescence
quartz hydration dating
period - 1600-25000 bp
mode - water diffusion into quartz leading
to the formation of a
hydration layer, thickness of the
hydration layer grown on a
fresh surface created in manufacturing
a quartz artifact is a
measure of the time elapsed since that
event
measures - quartz artifacts, art
authentication
synonyms
- hydration dating
226Ra/230Th - see
238U-230Th-226Ra
radioactive dating - see
radio-isotopic dating
radiocalcium dating - see
calcium41 dating
radiocarbon dating
period - 0-50000 bp
mode - incorporation of modern 14C stops
when the lifeform dies,
the water goes underground, the iron is
smelted, or air vesicles
in lava close, then through beta
particle emission reverts to
nitrogen, carbon-14 content decrease
relates to age
measure - ice cores, water, soils and
sediments, micro- and
macro-fossils, charcoal and wood, humic
acids, speleothems,
caliche, lime, marl, travertine, and
tufa, pollen, tree rings,
plant and animal tissues, iron,
carbonate deposits
synonyms
- carbon 14 dating, 14C dating
radiochlorine - see Chlorine
36
radiogenic Helium - see
4He/3He Thermochronometry
radiogenic nitrogen
mode - 14C decay product analysis
radio-isotopic dating
period - 0-4600 m. bp
mode - a radioactive 'parent' element
decays into a stable
'daughter' element at a constant rate,
the isotope must be
reasonably abundant and produce
daughter isotopes at a good
rate
measures - igneous material, hominid
evolution, orogenic belts,
rocks and minerals, metamorphic rocks,
whole rock or a single
mineral grain
synonyms
- radioactive dating, radioisotopic analysis
radioisotopic time scale
radiolarian analysis
measures - volcanogenic-siliceous slices
and blocks, boninitic
pillow rim, interpillow sediments
radioluminescence
period - 0-120000 bp
measures - zircon, potassic feldspar,
sediments
synonyms - luminescence
radiometric dating
period - 0-6 b. bp
mode - chronometric dating based on known
half-lives of
particular isotopes or the rate of
other cumulative changes in
atoms resulting from radioactivity
radiometric time scale
radio-oxygen - see 18O dating
Rb-Sr dating
period - 60 m. - 4.5 b. bp
measures - mica, cooling ages, uplift and
cooling history, rocks,
igneous rock, sedimentary rock source
of the mineral grains or
authigenic phases, biotite, muscovite,
or hornblende, heating
events, metamorphism, granite,
nepheline syenite, chrondite
meteorites, amphiboles, limestones
which also contain
abundant strontium
synonyms
- rubidium/strontium
Re-Os
measures - igneous rocks, iron meteorites,
molybdenite
relative dating
mode - gives the time of an event with
reference to another event
that is not worldwide in scale
relative patination - see
patination
rubidium/strontium - see
Rb-Sr dating
Samarium-Neodymium - see
Sm-Nd dating
sapropel chonology
measures - marine sediment, tephra
synonyms
- sapropel markers
scientific dating
mode - relative dating methods and absolute
dating methods
sea level variation
mode - global
seismostratigraphy
mode - subsurface units
sedimentation rate chronology
measures - lake sediment, marsh deposits,
past environments,
climate and erosion in a watershed,
regional vegetation patterns
and fire frequencies, sea bed deposits
sediment deposition
mode - establish a cave's minimum age
sequence dating
mode - place assemblages of artifacts into
relative order
measures - pottery
seriation
mode - artifact lenticular change,
artifact's popularity rises to a
high point and then trails off
measures - ceramics, points, material
cultural remains
Sm-Nd dating
mode - decay of 147Sm to 143Nd,
measures - volcanic deposits, komatiites,
time of eruption,
scheelite and tourmaline, gold
deposits, Sn-polymetallic ore
deposit, very old igneous and
metamorphic rocks, meteorites,
garnet
synonyms
- Samarium-Neodymium
soil geomorphology
spectroscopic dating
measures - wood, authenticity
speleothem deposition
mode - rough depositional necessary time
Sr, O
measures - volcanic rocks
stable isotope analysis
mode - stable isotopes of carbon, nitrogen
and oxygen
measures - hydrograph accuracy, water,
sedimentary organic
matter, carbonates, history of
discharge, bivalve shells,
climate history, land snail shells,
eggshells, diet
stalactite deposition
mode - establish a cave's minimum age from
the ages of
deposits
measures - stalactites
Standard Global Chronostratigraphic
Scale - see chronostratigraphy
stratigraphy
period - 0-4.5 b. bp
mode - based on the principle of
superposition, if there are layers
of deposits, those laid down first
will be on the bottom and
those laid down last will be on the
top
measure - geological strata, artifacts,
fossils
strontium/oxygen dating - see
Sr, O
style
measures - art, architecture
superimposition
mode - later image cut into earlier
measures - rock art
tectonic geomorphology
tectonostratigraphy
measures - island arcs, peninsulas,
highlands
Temporal Stream I
period - 0-2000 bp
Temporal Stream II
period - 0-250000 bp
tephrochronology
period - 0-5 m. bp
mode - tephra layers' physical, chemical,
spatial, and temporal
characteristics
measure - paleoclimate reconstruction,
paleoenvironmental
reconstruction, landscape
reconstruction, vulcanology
230Th/232Th - see
uranium/thorium dating
230Th/234U dating - see
uranium/thorium dating
230Th-234U-238U dating - see
uranium/thorium dating
thermochronology - see
thermochronometry
thermochronometry
period - 0-6 b. bp
mode - temperature-dependent systems that
record the time that
they passed through their specific
closure temperature
measures - apatite, monazite,
polymetamorphic terranes,
exhumation of surface rock,
metamorphism of sediments,
arc-continent collision zone, denudational history, cooling
history, mountain-building, exhumation,
subduction, faults,
tectonic hazards, landscape
development, tectonic
geomorphology, dating processes of
mountain building,
hydrocarbon exploration, sedimentary
burial history,
shallow-crustal and earth- and
planetary-surface processes,
timing and rates of development of
topographic relief, the
architecture and dynamics of orogenic
wedges, and feedbacks
between erosion, uplift, and climate at
a variety of scales,
weathering episodes, wildfires, and
extended time-temperature
histories, K-feldspar, zircon, crustal
thermal processes,
sedimentary basins, meteorites, erosion
and
paleotopographic histories,
low-temperature (<300°C) thermal
histories in upper crustal rocks,
titanite, provenance, landscape
evolution of mountain belts, tectonics,
continental margins,
cooling and uplift of blocks, episodic
rapid uplift, geodynamics
of orogenic belts, thermotectonic
evolution of cratons,
pegmatites, mylonitic rocks,
hornblende, alkali feldspars,
plate tectonics, biotite, granite,
convergent settings,
extensional settings, transpressional
settings, economic
mineralization, muscovite, titanite,
imaging of continents, quartz
synonyms - low-temperature
thermochronology, noble-gas
thermochronology, fission track
thermochronology, zircon
(U-Th)/He dating, 4He/3He
thermochronometry,
Time-temperature models, Detrital
thermochronometry,
U-Pb, noble-gas thermochronology,
argon-40/argon-39
Helium-lead dating
thermoluminescence
period - 30-1 m. bp
mode - uranium and thorium radiation dose
stored, released
by heating or the use of a laser beam
measure - rocks, minerals, pottery,
authenticity, quartz, feldspar,
diamond, calcite, hearths, fire-cracked
and fire treated rocks,
sediment, fired clay, terracotta,
bricks, tiles, obsidian, slag,
granite, rhyolite, stoneware,
porcelain, calcrete, shell, stalagmite,
zircon, Iceland spar, apatite,
meteorites, tephra, loess, sands,
silt
synonyms - TL, luminescence
thorium-230 dating - see
uranium/thorium dating
Th/Pb - see U/Pb dating
230Th/232Th - see
uranium/thorium dating
thorium-uranium
disequilibrium - see uranium/thorium dating
time scale
Astronomical Polarity Time Scale
Astronomical time scale (ATS)
cosmological time scale
geologic time scale
geomagnetic reversal time scale
isotopic time scale
magnetic anomaly time scale
orbital time scale
Paleontological Time Scale
Phanerozoic Time Scale
Prehistoric Time Scale
radiometric time scale
radioisotopic time scale
Temporal Stream I
Temporal Stream II
Time-temperature models - see
thermochronometry
TL - see thermoluminescence
total carbonate
tree ring dating - see
dendrochronology
tritium analysis
measures - hydrologics, groundwater flow
and recharge rates,
aquifers, tree rings, surface water
synonyms
- H3, 3H dating
tusk ring analysis
mode - seasonal growth layers
measures - famine records, birthing
reductions, elephants
typology
mode - seeks to identify and analyse
changes that will allow
artifacts to be placed into time
sequences
measures - artifacts, pottery, projectile
points
synonyms - type-series, typological studies
234U excess dating
period - 10000-2 m. bp
measures - groundwater, aquifer,
synonyms - 234U/238U dating
U-Fl-N dating
period - recent to mesozoic
mode - percolating ground water deposits
create relative
difference as age adds fluorine and
uranium and
removes nitrogen
measure - buried bone, recent intrusions,
teeth, antlers,
chronology for pits and midden
features, changes in pottery
attributes and in subsistence practices
synonyms - fluorine, uranium and nitrogen
tests, fluorine analysis
U/He dating - see (U-Th)/He
dating
U-Pb chronometry - see U/Pb
dating
U/Pb dating
period - 1 m. - 4.5 b. bp
mode - relies on the coupled chronometer
provided by the decay
of 238U to 206Pb, with a half-life of
4.46 billion years and 235U
to 207Pb, with a half-life of 704
million years, lead atoms created
by uranium decay are trapped in the
crystal and build up in
concentration with time
measures - rocks, monazite, fossil bones,
igneous and
metamorphic rocks, powdered whole
rocks, mineral
concentrates (isotope dilution
technique) or single grains,
zircon, baddeleyite, sphene, rutile,
powdered whole rocks,
apatite, titanite, orogenic
development, batholith, sedimentary
source, dykes, moon rocks and
meteorites, zirconolite,
siliciclastic sedimentary rocks,
sedimentary rocks, sandstone,
volcanic ash, volcanic eruptions,
continental movements and
mass extinctions, rhyolite, tuff,
metamorphism, hornblende,
pyrrhotite, tourmaline, gold
mineralization, granites, feldspar
phenocryst, intrusions
synonyms - U-Pb chronometry, zircon dating,
U-Th-Pb method,
thermochronometry, Pb-alpha activity,
Pb-Pb dating,
lead-lead dating, Th/Pb dating
U–Pb geochronology - see
geochronology, U/Pb dating
uranium disequilibrium series
- see uranium/thorium dating
238U-series - see
238U-230Th-226Ra
uranium-series - see
uranium/thorium dating
uranium series disequilibrium
- see uranium/thorium dating
uranium/thorium dating
period - 20 - 1 m. bp
mode - calcium-rich item such as a bone
buried in wet sediment
will absorb the parent uranium isotopes
more readily than it will
absorb the daughter thorium and
protactinium isotopes, the item
will then have an isotopic ratio of
parent to daughter isotopes
different from the surrounding sediments
-- a condition known
as disequilibrium
measures - organic marine sediments, bone,
wood, coral, stone,
and soil from deep water, cave, land
fall areas, speleothem,
interstadial and interglacial lignite,
calcrete, stalagmites,
carbonates, pottery, clays, soils, peat
deposits, weathered
alluvium, fluvial sediments,
ferruginous concretions and rinds,
coastal dunefield, continental
carbonates, travertines, caliches,
molluscs, teeth, lacustrine sediments,
evaporites, phosphorites,
shells (including egg shells),
carbonate sediments, early human
activity in caves, coastal plain,
invertebrate fossils, lake cores,
tephra, annually-laminated sediments,
impure carbonates, rock
art, calcite laminations, carbonate
coatings, calcite cement,
synonyms - 230TH/234U,
238U-234U-230Th-232Th, uranium
disequilibrium series, thorium-uranium
disequilibrium,
uranium-series, uranium series
disequilibrium, thorium-230,
230Th-234U-238U, 238U/230Th dating,
230Th/232Th,
(U-Th)/He dating
period - 1 m. - 0.5 b. bp
mode - with alpha particles (4He helium
nuclei) being emitted
throughout each decay series and
trapped within the lattice of
the host material
measures - zircon, hypersthene chondrites,
uplift and exhumation,
denudation, titanite, apatite,
structural and topographic
evolution
synonyms - (U-Th)/He thermochronometry,
(U-Th)/He
thermochonology, low-temperature
thermochronometry,
U/He dating
(U-Th)/He thermochronology -
see (U-Th)/He dating
(U-Th)/He thermochronometry -
see (U-Th)/He dating
U-Th-Pb method - see U/Pb
dating
238U-230Th-226Ra
measures - andesites and dacites, pumice,
fluvial sands
synonyms - 238U-series, excess (226)Ra,
226Ra/230Th
234U/238U dating - see 234U
excess dating
238U/230Th dating - see
uranium/thorium dating
238U-234U-230Th-232Th dating
- see uranium/thorium dating
varve chronology
period - 0-40000 bp
mode - counting annual silt deposits (i.e.,
varves) in former lakes
resulting from the summer melt of
glaciers, consists of
two layers; a thick light colored layer
of silt and fine sand which
forms in the spring and summer and a
thin dark colored layer of
clay forming in the fall and winter
measure - lake sediments, palaeoclimate,
terrestrial macrofossils,
organic carbon, marine sediments,
clays, rates of change in
climate and various ecosystems, silt,
fine sand, tephra
synonyms - annually laminated sediments, varved
clays, lake
sediment successions, laminated
sediments, annually laminated
lacustrine sediments
varved clays - see varve
chronology
weathering
mode - degree of weathering
measures - rock art
written records
period - to about 5000 BP
X-ray emission analysis
measures - bronze objects
x-ray fluorescence
measures - bronze objects, volcanic glass,
biogenic silica
zircon dating - see U/Pb
dating
zircon (U-Th)/He dating - see
thermochronometry