All language subtitles for 15 you tube Mathieu Duval - interview Q3 [360p] (2)

so yes adating is a polyodzymetric method

which mean that we look at the effect of uh

natural activity on

on some materials

like fussy teeth

when the teeth are buried so uh

surrounded by sediment

they will naturally receive radiations

from the elements that are inside the sediment

so you will have uranium

sodium potassium

so very different radioactive elements in the sediment

and when the radiations interact with the teeth

actually some electrons will get trapped

in the crystallatis of the

of the enamel

and this will give a rise to a signal

that you can measure with ESR

so that's how we measure it

we try to estimate to those

the radiation

those that has been absorbed by fossil tooth

since the organism died and was buried

so we in years of dating

we try to estimate the total dose of radiation

that has been absorbed by a sample over time

and at the same time

we go to the field

and we estimate the radioactivity of the sediment

of the sedimentary

and sedimentary environment

so which mean that if you

if you know the dose

that has been absorbed by your sample over time

and the amount of rejectivity

that your sample is receiving every year

you can estimate

for how long your sample has been exposed

to this natural activity

which is the age that we obtain

if we are not able to model

the evolution of the radio activity of our time

then we cannot obtain an accurate age

so this is one of the

of the limitations of the esidating method

that you need information not only about the sample

it said but about this surrounding environment

and if the rejectivity has change over time

and you are not able to model this change

then you cannot date the sample