GISP2 14-C (radiocarbon) measurements (Table 1).

REFERENCES:

Lal, D., A.J.T. Jull, G.S. Burr, and D.J. Donahue. 1997. Measurements of in
situ 14C concentrations in Greenland Ice Sheet Project 2 ice covering a 17
kyr time span: Implications to ice flow dynamics. Journal of Geophysical
Research 102:26505-26510.

DATA DESCRIPTION:

This file contains the radiocarbon (14C) data from Table 1 of Lal and Jull
(1997) (14C concentrations in CO and CO2 for selected depths in the GISP2
ice core). 

Approximate age of ice is based on layer counting and delta 18O data for
trapped air (Grootes et al., 1993; Sowers et al., 1993; Meese et al.,
1994a; Stuiver et al., 1995).  Tube #'s 16-34 are in the firn. Tube # 89
was not measured (see below).  Trapped air concentration was not measured
for tube #'s 16, 18, and 34. 

Typical errors in determination of 14C concentration in recent samples are
~ 50-60 atoms/g, which includes statistical errors and uncertainties in
line blanks.  The larger errors in the case of samples from tubes 18 and
34 arise from multiple extractions, and in samples from depths 100.4 to
1518 from 14C-decay corrections. 

For Tube # 89:  Result of Wilson and Donahue (1992). In this experiment,
CO2 was recovered by sublimation of ice from 90.6 m and 91.4 m depth in
the GISP2 ice core. 

Note:  Value for trapped air in sample for tube #127 is questionable.

999999 = no data.

Columns are as follows:

Tube: ice core tube #
depth top: depth top in meters
depth bottom: depth bottom in meters
age: approximate age in years
mass: mass of sample in kg
Air: volume of trapped air in sample (cm^3 air/liter sample)
14C(CO): decay-corrected 14C concentration (atoms/g) in CO
14C(CO2): decay-corrected 14C concentration (atoms/g) in CO2

DATA:

Tube	depth top (m)	depth bottom (m)	age (yr)	mass (kg)	Air	14C(CO)	+/-	14C(CO2)	+/-		

16	16	17	50	3.1	999999	1280	90	0	30
18	18	19	50	2.9	999999	510	100	1910	150
31	31	32	50	3.4	4.3	460	100	100	100
34	34	35	50	1.7	999999	995	60	1965	200	
88	87.0	87.8	225	3.1	67.6	180	70	1260	60
89	90.6	91.4	225	999999	999999	999999	999999	900	999999	
101	100.4	100.99	275	2.3	66.7	80	70	1113	60
102	100.99	101.2	275	0.58	104.1	655	60	1533	60
126	125.50	126	375	1.5	77.9	120	70	1950	50
127	126.00	126.30	275	0.98	136.5	100	70	1860	60
1519	1518.00	1518.8	9470	2.6	75.1	3860	180	1860	180
1624	1623.00	1623.8	10770	2.5	76.7	940	190	2540	190
1699	1698.13	1698.89	12390	2.8	77.9	50	250	3530	250
1750	1749.00	1749.8	13750	2.7	86.1	915	325	3270	320
1838	1837.00	1837.8	16200	2.8	80.9	2235	470	4060	470