. 2016 Sep 21;11(9):e0160123. doi: 10.1371/journal.pone.0160123

Table 3. Dose rate data, equivalent doses and OSL ages for sediment samples from Riwi.

Sample	SU	Depth (cm)	Water (%)^#	Environmental dose rate (Gy/ka)				D_e value (Gy)^$	Number of grains^*	Overdispersion (%)^&	Age (ka)^{^}	P-value
				Beta	Gamma	Cosmic	Total
Riwi-4	2	13	1.8	1.06 ± 0.05	0.63 ± 0.03	0.05 ± 0.01	1.77 ± 0.06	13.0 ± 0.1	268 (214)	28 ± 1	7.3 ± 0.3 (0.2)
Riwi-5	2	17	4.3	0.93 ± 0.05	0.65 ± 0.03	0.05 ± 0.01	1.66 ± 0.06	11.7 ± 0.2	234 (191)	31 ± 2	7.1 ± 0.3 (0.2)
									*Weighted mean =*		7.2 ± 0.3	0.21
Riwi-2	?	20	3.8	1.11 ± 0.05	0.64 ± 0.03	0.05 ± 0.01	1.83 ± 0.06	49.9 ± 1.7 (53%)15.3 ± 0.8 (27%)	186	118 ± 6	27.3 ± 1.4 (1.0)8.4 ± 0.5 (0.5)
Riwi-6	?	20	1.5	1.13 ± 0.06	0.63 ± 0.03	0.05 ± 0.01	1.84 ± 0.06	46.1 ± 0.8 (59%)12.7 ± 0.3 (41%)	217	71 ± 4	25.1 ± 1.1 (1.0)6.9 ± 0.3
Riwi-1	6	22	7.9	0.92 ± 0.05	0.67 ± 0.03	0.05 ± 0.01	1.67 ± 0.06	57.8 ± 1.0	227 (198)	32 ± 2	34.6 ± 1.5 (0.9)
Riwi-7	7	23	1.5	1.09 ± 0.05	0.63 ± 0.03	0.05 ± 0.01	1.79 ± 0.06	63.3 ± 1.2	211 (179)	33 ± 2	35.3 ± 1.5 (0.9)
Riwi-3	7	24	3.2	1.02 ± 0.05	0.64 ± 0.03	0.05 ± 0.01	1.73 ± 0.06	57.4 ± 1.4	179 (146)	64 ± 4	33.1 ± 1.5 (1.1)
Riwi-8	7	26	3.0	1.06 ± 0.05	0.64 ± 0.03	0.05 ± 0.01	1.77 ± 0.06	67.0 ± 1.1	212 (164)	30 ± 2	37.8 ± 1.6 (0.9)
									*Weighted mean =*		35.6 ± 1.3	0.13
Riwi-9	8	29	2.4	0.98 ± 0.05	0.63 ± 0.03	0.05 ± 0.01	1.69 ± 0.06	64.1 ± 1.4	185 (159)	34 ± 2	38.0 ± 1.7 (1.1)
Riwi-10	8	31.5	5.0	0.97 ± 0.05	0.65 ± 0.03	0.05 ± 0.01	1.70 ± 0.06	69.3 ± 1.4	183 (155)	30 ± 2	40.8 ± 1.8 (1.1)
Riwi-11	8	34	1.8	0.98 ± 0.05	0.63 ± 0.03	0.05 ± 0.01	1.69 ± 0.06	68.0 ± 1.4	207 (185)	27 ± 2	40.2 ± 1.8 (1.1)
									*Weighted mean =*		39.6 ± 1.5	0.49
Riwi-12	9	36.5	0.6	1.04 ± 0.05	0.65 ± 0.03	0.05 ± 0.01	1.77 ± 0.06	68.9 ± 1.3	203 (167)	29 ± 2	39.0 ± 1.7 (1.0)
Riwi-13	10	39	2.4	1.09 ± 0.05	0.65 ± 0.03	0.05 ± 0.01	1.82 ± 0.06	72.9 ± 1.9	198 (175)	36 ± 2	40.1 ± 1.9 (1.3)
Riwi-14	10	42	4.4	1.02 ± 0.05	0.65 ± 0.03	0.04 ± 0.01	1.74 ± 0.06	71.4 ± 1.2	221 (177)	35 ± 2	40.9 ± 1.8 (1.0)
Riwi-15	10	44.5	2.2	0.99 ± 0.05	0.65 ± 0.03	0.04 ± 0.01	1.72 ± 0.06	68.6 ± 1.6	186 (158)	34 ± 2	40.0 ± 1.8 (1.2)
Riwi-16	10	47	1.3	1.05 ± 0.05	0.65 ± 0.03	0.04 ± 0.01	1.78 ± 0.06	68.2 ± 1.3	184 (149)	29 ± 2	38.4 ± 1.7 (1.0)
Riwi-17	10	50	1.7	1.04 ± 0.05	0.63 ± 0.03	0.04 ± 0.01	1.75 ± 0.06	77.4 ± 1.8	173 (144)	33 ± 2	44.3 ± 2.0 (1.3)
Riwi-18	10	52	1.7	0.99 ± 0.05	0.63 ± 0.03	0.04 ± 0.01	1.69 ± 0.06	70.9 ± 1.5	185 (161)	30 ± 2	41.9 ± 1.9 (1.2)
Riwi-19	10	55	1.7	0.99 ± 0.05	0.63 ± 0.03	0.04 ± 0.01	1.69 ± 0.06	72.3 ± 1.5	214 (189)	30 ± 2	42.9 ± 1.9 (1.2)
Riwi-20	10	60	2.0	0.98 ± 0.05	0.63 ± 0.03	0.04 ± 0.01	1.68 ± 0.06	69.2 ± 1.4	203 (182)	31 ± 2	41.1 ± 1.8 (1.1)
									*Weighted mean =*		41.1 ± 1.6	0.43
Riwi-21	11	63	1.9	1.00 ± 0.05	0.63 ± 0.03	0.04 ± 0.01	1.70 ± 0.06	73.0 ± 2.2	174 (137)	35 ± 2	43.0 ± 2.1 (1.3)
Riwi-22	11	66	4.9	0.97 ± 0.05	0.65 ± 0.03	0.04 ± 0.01	1.69 ± 0.06	76.2 ± 1.9	178 (164)	35 ± 2	45.0 ± 2.1 (1.4)
Riwi-23	11	71	5.5	0.98 ± 0.05	0.65 ± 0.03	0.04 ± 0.01	1.70 ± 0.06	73.4 ± 1.8	208 (180)	32 ± 2	43.1 ± 2.0 (1.2)
Riwi-24	11	74	4.0	0.97 ± 0.05	0.64 ± 0.03	0.04 ± 0.01	1.68 ± 0.06	67.7 ± 1.2	258 (221)	34 ± 2	40.2 ± 1.7 (1.0)
Riwi-25	11	77	3.4	0.95 ± 0.05	0.64 ± 0.03	0.04 ± 0.01	1.66 ± 0.06	72.9 ± 1.2	217 (183)	28 ± 2	44.0 ± 1.9 (1.1)
									*Weighted mean =*		42.8 ± 1.6	0.58
Riwi-26	12	80	1.7	0.87 ± 0.04	0.63 ± 0.03	0.04 ± 0.01	1.56 ± 0.05	66.2 ± 1.3	135 (117)	29 ± 2	42.4 ± 1.9 (1.2)
Riwi-27	12	83	3.0	0.90 ± 0.05	0.64 ± 0.03	0.04 ± 0.01	1.61 ± 0.05	68.2 ± 1.5	142 (125)	27 ± 2	42.4 ± 1.9 (1.2)
Riwi-28	12	85.5	4.5	0.94 ± 0.05	0.65 ± 0.03	0.04 ± 0.01	1.65 ± 0.06	71.6 ± 1.8	141 (126)	35 ± 2	43.3 ± 2.0 (1.4)
Riwi-29	12	88	4.8	0.93 ± 0.05	0.65 ± 0.03	0.04 ± 0.01	1.65 ± 0.06	76.8 ± 2.1	130 (113)	37 ± 3	46.5 ± 2.2 (1.6)
Riwi-30	12	91	4.2	0.92 ± 0.05	0.65 ± 0.03	0.04 ± 0.01	1.63 ± 0.06	74.0 ± 1.5	158 (129)	29 ± 2	45.3 ± 2.0 (1.2)
Riwi-31	12	93	0.3	0.89 ± 0.05	0.62 ± 0.03	0.04 ± 0.01	1.57 ± 0.05	76.6 ± 1.6	160 (135)	32 ± 2	48.8 ± 2.2 (1.4)
Riwi-32	12	96	1.9	0.93 ± 0.05	0.63 ± 0.03	0.04 ± 0.01	1.62 ± 0.06	73.3 ± 1.5	156 (135)	24 ± 2	45.2 ± 2.0 (1.2)
Riwi-33	12	99	1.9	0.93 ± 0.05	0.63 ± 0.03	0.03 ± 0.01	1.62 ± 0.06	78.5 ± 1.9	136 (132)	34 ± 3	48.4 ± 2.2 (1.5)
Riwi-34	12	102	2.9	0.90 ± 0.05	0.64 ± 0.03	0.03 ± 0.01	1.60 ± 0.05	69.4 ± 1.9	140 (116)	42 ± 3	43.5 ± 2.1 (1.5)
Riwi-35	12	105	2.4	0.94 ± 0.05	0.63 ± 0.03	0.03 ± 0.01	1.63 ± 0.06	75.8 ± 2.3	117 (110)	29 ± 2	46.4 ± 2.3 (1.7)
Riwi-36	12	108	1.9	0.95 ± 0.05	0.63 ± 0.03	0.03 ± 0.01	1.65 ± 0.06	84.6 ± 1.8	130 (105)	29 ± 2	51.3 ± 2.3 (1.4)
Riwi-37	12	110	3.4	0.94 ± 0.05	0.64 ± 0.03	0.03 ± 0.01	1.64 ± 0.06	80.2 ± 2.3	128 (114)	38 ± 3	48.9 ± 2.4 (1.7)
									*Weighted mean =*		46.7 ± 1.7	0.075

^#Represent the current measured water content of the sediment. A relative uncertainty of ±40% (at 1σ) was assigned to each estimate of water content. A water content of 5 ± 2% was used for all samples in calculations of dose rate.

^$D_e values for all samples were obtained using the central age model (CAM), except for Riwi-2 and Riwi-6 where the finite mixture model (FMM) was used. The D_e values are those for the two components that represent the highest number of grains and the proportions are indicated in brackets.

*Numbers in brackets represent the number of grains included in the CAM D_e value after identification and rejection of outlier (nMAD) grains.

^&The OD values are for the D_e distributions that include all D_e values, including those identified as outliers. The OD values for the samples where the outliers were rejected are provided in S1 Table.

^Numbers in brackets represent the random-only error on the age.