Before Present (BP) is a year numbering system, used for the far past times, relating dates to the year 1950. For example, 12,000 BP means 12,000 years before 1950. This is a commonly-used year numbering system in carbon-14 dating. ==Why 1950?== Scientists established 1950 as the benchmark date for the BP system because it is the year in which calibration curves for carbon-14 dating were established. 1950 also predates atmospheric testing of nuclear weapons, which altered the global balance of carbon-12 to carbon-14, which in turn altered the calibration curves for carbon-14 dating. ==See also== *bya *mya (unit) ==References== #[http://vcourseware.calstatela.edu/VirtualDating/files/RC_3.html AD or BC? Questions at California State University, Los Angeles] Units of time
What is special about 1950?? User:Georgia guy 22:34, 14 Apr 2005 (UTC) :I'm looking into this for an answer. --User:Viriditas | User_talk:Viriditas 06:25, 18 May 2005 (UTC) ::Found it. Adding... --User:Jemiller226 18:10, 21 May 2005 (UTC)
See other meanings of words starting from letter:
Words begining with Before_Present:
Before_Present
Before_Present
Before Present
Before Present (BP) is a year numbering system, used for the far past times, relating dates to the year 1950. For example, 12,000 BP means 12,000 years before 1950. This is a commonly-used year numbering system in carbon-14 dating. ==Why 1950?== Scientists established 1950 as the benchmark date for the BP system because it is the year in which calibration curves for carbon-14 dating were established. 1950 also predates atmospheric testing of nuclear weapons, which altered the global balance of carbon-12 to carbon-14, which in turn altered the calibration curves for carbon-14 dating. ==See also== *bya *mya (unit) ==References== #[http://vcourseware.calstatela.edu/VirtualDating/files/RC_3.html AD or BC? Questions at California State University, Los Angeles] Units of time
Before Present
What is special about 1950?? User:Georgia guy 22:34, 14 Apr 2005 (UTC) :I'm looking into this for an answer. --User:Viriditas | User_talk:Viriditas 06:25, 18 May 2005 (UTC) ::Found it. Adding... --User:Jemiller226 18:10, 21 May 2005 (UTC)
See other meanings of words starting from letter:
B
BA | BC | BD | BE | BF | BG | BH | BI | BJ | BK | BL | BM | BN | BO | BP | BR | BS | BT | BU | BW | BX | BY | BZ |Words begining with Before_Present:
Before_Present
Before_Present
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