Table 3 Application of dating criteria (Step 1) from11
From: A comprehensive database of quality-rated fossil ages for Sahul’s Quaternary vertebrates
Dating technique | Dated remain/material | m* | m | B | C |
|---|---|---|---|---|---|
radiocarbon (14C) detection limit=55 ka | bone collagen dentin collagen | - collagen preservation checked with C:N ratio and % N and using ultrafiltration, XAD-2, ninhydrin pre-treatments - dating on individual amino acids and using ultrafiltration, XAD-2, ninhydrin pre-treatments | - ABA, AAA or acid-wash pre-treatments - decalcification but no info about collagen presence on bone or dentine - collagen purification difficulties reported | - mixture of multiple bones or teeth | |
wood seeds | - dating of alpha-cellulose isolated from plant remains | ||||
gut contents coprolites | - dating of alpha-cellulose isolated from digestive remains | ||||
corals, shells | - dating of carbonate fraction if outer surfaces removed with mechanical grinding and acid wash, and if X-ray diffraction shows that recrystallization is insignificant | - dating without treatment and x-ray diffraction analysis | |||
eggshells | - dating of carbonate fraction with stringent removal of secondary carbonate with grinding and acid etching | - dating without treatment | - organic fraction | ||
charcoal | - ABOX and chlorate oxidation pre-treatments | - ABA, AAA or acid-wash pre-treatments | |||
Inorganic calcite (speleothem, soil carbonate) bulk soil organics | not acceptable | not acceptable | not acceptable | not acceptable | |
amino acid racemization (AAR) detection limit=1Ma | eggshell otolith | - direct date on the target species - absolute age requires demonstrated closed-system behaviour and multiple analyses replicated within low uncertainties and calibration using independent dating techniques and models describing racemization kinetics | - direct date on the target species - relative age on demonstrated closed-system material and multiple analyses are replicated within low uncertainties within a limited geographic region (mean annual temperature range<±1 °C) | - unknown thermal history - burnt materials - no local calibration | |
bone tooth | not acceptable | not acceptable | not acceptable | not acceptable | |
Uranium-series detection limit=500 ka | tooth | - combined with ESR dating (see Table 5) | - demonstrated closed-system continuous profiles through tooth with laser-ablation ICP-MS, combined with U-uptake modelling - demonstrated closed-system spot sampling with ICP-MS or TIMS, combined with modelling | - ICP-MS or TIMS without modelling | |
bone | - continuous profiles through bone with laser-ablation ICP-MS, combined with uptake modelling - spot sampling with ICP-MS or TIMS, combined with modelling | - ICP-MS or TIMS without modelling | |||
eggshell | - eggshell with stringent removal of secondary carbonate, acid wash, and ICP-MS or TIMS | ||||
closed-system of no body remains (e.g., speleothems, corals | - ICP-MS or TIMS with a detrital correction | ||||
electron spin resonance (ESR) detection limit=1 Ma | tooth enamel | - direct age, combined ESR and closed-system U-series modelling (CSUS-ESR) - ESR ages with low U content in dentine and enamel (model independent); internal dose rate <10% of total dose rate; gamma dose rate measured in situ | - direct age, EU and LU ages that are model dependent with a p-value derived from a U-series estimate (US-ESR) - ESR ages with low U content in dentine and enamel (model independent); internal dose rate <10% of total dose rate; gamma dose rate assumed from sediment attached to tooth | - early U-uptake model (EU) and linear U-uptake model (LU), with no U-series constraint on the possible history of U-uptake - ESR ages with low U content in dentine and enamel (model independent); internal dose rate >10% of total dose rate | |
Luminescence detection limit=1 Ma | sediment | - single-grain OSL ages for well-bleached or partially bleached sediments that can be modelled - single-grain OSL, single-aliquot OSL or multi-aliquot TL ages on demonstrated well-bleached sediments or sediments with high likelihood of being fully bleached at deposition. Resetting of the luminescence signal needs to be demonstrated explicitly | - single-grain OSL ages that cannot be modelled - single-aliquot OSL or multi-aliquot TL ages for mixed or partially-bleached sediments | ||
organic material (e.g., bone) | not acceptable | not acceptable | not acceptable | not acceptable |
