Cosmogenic ¹⁰Be exposure ages of glacial erratics, Ford Ranges, Marie Byrd Land

Please cite:

Stone J.O., Balco G., Sugden D.E., Caffee M.W., Sass L.C. III, Cowdery S.G. and Siddoway C. (2003) Late Holocene deglaciation of Marie Byrd Land, West Antarctica Science 299, 99-102, in reference to these data.

Sample	Latitude	Longitude	Altitude	Scaling factor^1	Scaling factor^1	Thickness correction	Horizon correction	^10Be production rate^2	[^10Be]^3	Exposure age^4
	(° S)	(° W)	(m)	(spallation)	(muons)			(atom/g/yr)	(10^4 atom/g)	(yr)
Migmatite Ridge - Eastern Fosdick Mtns
99-MBL-011-MGM	76.532	144.462	1042	3.381	1.866	0.948	1.000	16.1 ± 1	7.58 ± 0.34	4720 ± 350
99-MBL-008-MGM	76.539	144.500	991	3.235	1.822	0.935	1.000	15.2 ± 0.9	6.27 ± 0.21	4140 ± 280
99-MBL-009-MGM	76.539	144.500	991	3.235	1.822	0.956	1.000	15.5 ± 0.9	6.42 ± 0.21	4150 ± 280
99-MBL-019-MGM	76.558	144.446	817	2.774	1.676	0.948	1.000	13.2 ± 0.8	2.9 ± 0.2	2200 ± 200
99-MBL-021-MGM	76.558	144.446	817	2.774	1.676	0.931	1.000	13.0 ± 0.8	3.16 ± 0.14	2440 ± 180
Mt Passel - Denfeld Range
99-MBL-038-PAS	76.884	144.942	726	2.555	1.604	0.952	1.000	12.2 ± 0.7	4.33 ± 0.26	3550 ± 300
99-MBL-043-PAS	76.868	145.077	569	2.209	1.484	0.952	1.000	10.6 ± 0.6	1.92 ± 0.08	1820 ± 130
99-MBL-044-PAS	76.884	144.958	443	1.958	1.393	0.948	0.991	9.3 ± 0.5	1.61 ± 0.29	1750 ± 330
Mt Van Valkenberg - Clark Mtns
01-MBL-002-VVB	77.310	142.112	1127	3.636	1.941	0.944	0.996	17.1 ± 1	10.9 ± 0.25	6370 ± 410
01-MBL-005-VVB	77.311	142.111	1125	3.630	1.940	0.915	0.997	16.6 ± 1	10.21 ± 0.24	6160 ± 390
01-MBL-007-VVB	77.313	142.114	1071	3.467	1.891	0.931	1.000	16.2 ± 1	6.25 ± 0.23	3860 ± 270
01-MBL-008-VVB	77.313	142.105	1052	3.411	1.875	0.956	0.998	16.3 ± 1	5.4 ± 0.17	3310 ± 220
Mt Darling / Mt Spencer - Allegheny Mtns
01-MBL-055-DAR	77.261	143.339	1076	3.482	1.896	0.956	0.999	16.7 ± 1	15.52 ± 0.42	9320 ± 610
01-MBL-058-DAR	77.262	143.340	1075	3.479	1.895	0.940	1.000	16.4 ± 1	15.11 ± 0.43	9240 ± 610
01-MBL-064-DAR	77.265	143.328	988	3.227	1.819	0.948	0.995	15.3 ± 0.9	10.56 ± 0.25	6930 ± 440
01-MBL-070-DAR	77.268	143.323	884	2.945	1.731	0.952	0.996	14.0 ± 0.8	6.41 ± 0.17	4580 ± 300
01-MBL-073-DAR	77.269	143.323	849	2.855	1.702	0.965	0.988	13.7 ± 0.8	5.24 ± 0.14	3840 ± 250
01-MBL-039-SPC	77.290	143.339	751	2.614	1.624	0.931	0.998	12.2 ± 0.7	20.3 ± 0.48	16700 ± 1070
01-MBL-041-SPC	77.291	143.349	694	2.481	1.579	0.935	0.999	11.6 ± 0.7	13.35 ± 0.4	11500 ± 770
Fleming Peaks - Eastern Sarnoff Mtns
01-MBL-083-FLM	77.254	144.435	691	2.474	1.577	0.965	1.000	12.0 ± 0.7	5.92 ± 0.15	4940 ± 320
01-MBL-088-FLM	77.255	144.444	660	2.404	1.553	0.935	1.000	11.3 ± 0.7	4.83 ± 0.17	4270 ± 290
Mt Blades - Western Sarnoff Mtns
99-MBL-069-BLD	77.161	145.329	632	2.343	1.531	0.948	0.997	11.1 ± 0.7	7.56 ± 0.23	6810 ± 450
99-MBL-073-BLD	77.161	145.318	506	2.080	1.438	0.952	0.990	9.9 ± 0.6	3.61 ± 0.15	3660 ± 260
99-MBL-076-BLD	77.163	145.308	482	2.033	1.421	0.948	0.986	9.6 ± 0.6	2.87 ± 0.32	3010 ± 380
Mt Rea / The Billboard - Western Sarnoff Mtns
01-MBL-133-BBD	77.074	145.698	779.6	2.682	1.646	0.931	0.999	12.5 ± 0.7	49.29 ± 1.12	39700 ± 2540
99-MBL-055-BBD	77.073	145.692	740	2.588	1.615	0.940	0.997	12.2 ± 0.7	122.71 ± 1.5	103000 ± 6400
01-MBL-135-BBD	77.073	145.692	740	2.588	1.615	0.944	0.997	12.2 ± 0.7	133.65 ± 3.04	112000 ± 7300
01-MBL-140-REA	77.078	145.584	717.2	2.534	1.597	0.899	0.994	11.4 ± 0.7	36.79 ± 0.71	32500 ± 2000
99-MBL-056-BBD	77.072	145.688	715	2.529	1.595	0.969	0.997	12.3 ± 0.7	12.72 ± 0.34	10400 ± 680
99-MBL-059-BBD	77.073	145.686	712	2.522	1.593	0.961	0.997	12.1 ± 0.7	35.29 ± 0.82	29300 ± 1900
01-MBL-138-BBD	77.073	145.686	702	2.499	1.585	0.931	0.997	11.7 ± 0.7	107.75 ± 1.82	94400 ± 6000
01-MBL-143-REA	77.077	145.587	685	2.460	1.572	0.956	0.998	11.8 ± 0.7	21.88 ± 0.63	18600 ± 1200
01-MBL-146-REA	77.071	145.595	616	2.308	1.519	0.956	0.997	11.1 ± 0.7	20.71 ± 0.48	18800 ± 1200
01-MBL-149-REA	77.071	145.595	610	2.295	1.515	0.948	0.997	10.9 ± 0.6	29.06 ± 0.66	26800 ± 1700
99-MBL-061-REA	77.068	145.574	489	2.047	1.426	0.940	0.998	9.7 ± 0.6	3.01 ± 0.19	3120 ± 270
99-MBL-062-REA	77.068	145.574	489	2.047	1.426	0.969	0.998	10.0 ± 0.6	3.37 ± 0.11	3390 ± 230
01-MBL-151-REA	77.068	145.565	433	1.939	1.386	0.948	0.998	9.2 ± 0.5	3.1 ± 0.12	3360 ± 240
01-MBL-153-REA	77.068	145.565	404	1.885	1.366	0.935	0.996	8.8 ± 0.5	2.43 ± 0.1	2750 ± 200
99-MBL-066-REA	77.068	145.548	287	1.679	1.286	0.944	0.990	7.9 ± 0.5	2.16 ± 0.07	2740 ± 190
01-MBL-161A-REA	77.061	145.570	172	1.492	1.211	0.952	0.992	7.1 ± 0.4	1.85 ± 0.12	2600 ± 220
01-MBL-163-REA	77.060	145.569	162	1.477	1.205	0.931	0.993	6.9 ± 0.4	1.64 ± 0.11	2380 ± 210
Mt Rea / Mt Dolber col
99-MBL-080-GAP	77.084	145.558	352	1.791	1.330	0.952	0.995	8.5 ± 0.5	2.02 ± 0.16	2370 ± 230
99-MBL-081-GAP	77.084	145.558	350	1.788	1.328	0.952	0.994	8.5 ± 0.5	2.11 ± 0.12	2480 ± 200
99-MBL-083/3-GAP	77.082	145.546	245	1.609	1.258	0.961	0.987	7.7 ± 0.5	1.49 ± 0.08	1940 ± 160
99-MBL-084-GAP	77.082	145.545	237	1.596	1.253	0.940	0.987	7.5 ± 0.4	0.44 ± 0.05	590 ± 70
01-MBL-157/3-GAP	77.081	145.544	226	1.578	1.246	0.944	0.971	7.3 ± 0.4	0.22 ± 0.07	300 ± 90

¹ Correction factor relative to 1013.25 mbar and latitude > 60°, based on estimated mean annual air pressure, as described by Stone (2000).

² Assumed ¹⁰Be production rates: spallation: 4.95 ± 0.30 atom/g SiO₂/yr, negative muon capture: 0.11 ± 0.02 atom/g SiO₂/yr, at 1013.25 mbar and latitude > 60° (Stone, 2000).

³ Measured relative to LLNL working ¹⁰Be/⁹Be standards, traceable to ICN ¹⁰Be standard. Uncertainties propagated at ±1s level including all known sources of analytical error.

⁴ Calculated simple exposure ages. If pre-exposed samples are old erratics that were overrun and buried during previous glaciations, these are lower limits to the cumulative exposure time. Uncertainties are ±1s (68% confidence) including ¹⁰Be measurement uncertainties (see above) and assumed ±6% error in ¹⁰Be production rate.