Table 1. 40Ar/39Ar Step Heating Data – 01-524 K-feldspar
											
Temp
(C)	40Ar/39Ar
	38Ar/39Ar
(10-2)	37Ar/39Ar
(10-4)	36Ar/39Ar
(10-3)	39Ar (mol)
(10-15)	Cumulative
39Ar (%)	40Ar*
(%)	40Ar*/39Ar	Calculated Age
(Ma) ± 1 	Cl/K
10-5	
01-524 (HE01IRS001)  K-feldspar, 2.00 mg, J = 0.0089150
	
450	625.7	26.59	24.97	89.65	0.6920	0.2	95.8	599.3	3333 ± 10	2140	
450	66.25	12.99	13.68	41.06	0.4199	0.3	81.6	54.09	710.0 ± 7.8	332	
500	87.63	12.68	9.871	14.80	1.085	0.6	95.0	83.25	1002 ± 5.7	358	
500	35.32	10.80	7.734	7.196	1.066	0.9	93.9	33.15	467.1 ± 3.5	108	
550	77.00	11.47	5.438	6.627	2.330	1.5	97.4	75.00	923.6 ± 2.2	207	
550	29.71	10.70	13.57	4.004	2.347	2.1	95.9	28.51	408.5 ± 1.8	104	
600	84.72	11.93	8.614	6.371	3.037	2.9	97.7	82.81	997.5 ± 1.5	273	
600	31.10	10.60	17.83	3.246	2.594	3.5	96.8	30.11	429.0 ± 1.6	91	
650	68.88	11.18	12.77	5.718	2.966	4.3	97.5	67.18	846.7 ± 3.3	167	
650	39.44	10.07	8.086	2.393	2.581	5.0	98.1	38.70	534.8 ± 1.6	18	
700	58.29	10.84	9.623	3.438	2.733	5.7	98.2	57.22	743.6 ± 2.6	125	
700	52.69	10.56	13.87	2.126	2.915	6.4	98.8	52.02	687.4 ± 2.7	88	
750	64.37	10.49	6.131	2.137	3.138	7.3	99.0	63.70	811.4 ± 1.3	78	
750	62.77	10.10	4.561	1.959	3.521	8.2	99.0	62.18	795.6 ± 2.6	23	
800	68.49	10.55	11.43	2.564	3.304	9.0	98.9	67.70	851.9 ± 1.1	86	
800	69.96	10.27	5.922	2.834	3.276	9.9	98.8	69.08	865.7 ± 3.7	44	
850	71.82	10.49	4.837	2.854	3.918	10.9	98.8	70.96	884.3 ± 2.5	77	
850	70.19	9.979	8.074	1.713	5.618	12.4	99.2	69.66	871.5 ± 2.8	7	
900	72.51	10.13	6.136	1.532	5.787	13.9	99.3	72.04	894.9 ± 2.3	28	
900	73.61	10.29	10.81	1.958	7.571	15.8	99.2	73.01	904.4 ± 1.7	50	
950	73.06	10.37	10.62	2.142	7.156	17.7	99.1	72.39	898.3 ± 2.3	61	
950	72.74	10.19	0.6219	0.9381	9.911	20.3	99.6	72.43	898.7 ± 1.4	40	
950	74.41	10.34	6.400	1.870	13.12	23.7	99.2	73.84	912.5 ± 1.9	58	
1000	74.88	10.63	5.249	3.025	7.966	25.8	98.8	73.95	913.6 ± 2.3	96	
1000	77.78	10.63	3.250	1.663	12.18	28.9	99.3	77.27	945.4 ± 3.0	100	
1050	77.89	10.77	8.381	2.538	12.54	32.2	99.0	77.09	943.7 ± 2.0	116	
1050	80.19	10.72	4.190	1.975	17.01	36.6	99.2	79.56	967.1 ± 1.5	112	
1050	82.06	10.61	6.539	2.069	22.19	42.4	99.2	81.43	984.6 ± 2.9	97	
1100	81.98	10.78	11.47	3.872	13.10	45.8	98.6	80.78	978.6 ± 3.4	115	
1100	84.72	10.61	7.292	3.093	20.68	51.2	98.9	83.79	1007 ± 1.6	94	
1100	86.73	10.69	6.430	3.029	28.40	58.5	98.9	85.80	1025 ± 3.2	105	
1100	89.48	10.79	6.574	3.252	26.53	65.4	98.9	88.48	1049 ± 1.1	119	
1100	91.38	10.45	12.30	3.962	18.10	70.1	98.7	90.19	1064 ± 2.6	69	
1100	93.28	10.75	6.540	4.459	17.86	74.8	98.6	91.94	1080 ± 1.8	109	
1100	94.35	10.79	1.722	5.250	15.58	78.8	98.3	92.74	1087 ± 4.1	112	
1100	94.52	10.44	7.267	7.139	19.54	83.9	97.7	92.39	1084 ± 3.7	58	
1200	91.91	10.73	13.71	4.364	10.40	86.6	98.6	90.56	1068 ± 2.2	107	
1230	92.37	10.46	6.448	2.758	11.92	89.7	99.1	91.50	1076 ± 2.0	72	
1260	91.80	10.55	4.321	2.838	12.07	92.9	99.1	90.91	1071 ± 1.4	86	
1290	86.24	10.70	4.459	3.922	13.37	96.3	98.6	85.05	1018 ± 1.4	103	
1320	86.00	10.41	7.360	3.988	9.043	98.7	98.6	84.79	1016 ± 1.0	62	
1350	96.27	10.89	13.36	4.474	2.172	99.2	98.6	94.94	1106 ± 2.8	129	
1450	96.70	11.21	17.26	15.24	2.910	100.0	95.3	92.17	1082 ± 3.5	147	
											
Totals					384.7			82.46	994.2 ± 2.3		
								
e = 5.543 x 10-10 a-1	Fluence monitor, GA1550 Biotite, 40Ar*/39ArK = 6.3137