Characterization of Modern and Fossil Mineral Dust Transported to High Altitude in the Western Alps: Saharan Sources and Transport Patterns

Table 1

Sample depth (meter water equivalent, m weq.) for the Colle Gnifetti (CG) ice-core samples (upper part), sample name for the Jungfraujoch (JFJ) samples (lower part), age of sample, ⁸⁷Sr/⁸⁶Sr and ¹⁴³Nd/¹⁴⁴Nd isotopic compositions with 2σ (2 standard errors of the mean), and Nd isotopic ratios expressed as epsilon units.

Sample depth (m weq.)	Apparent age^a	^87Sr/^86Sr FC^b	2σ Sr× 10^−6	^143Nd/^144Nd FC^c	2σ Nd × 10^−6	𝜀Nd (0)^d
10.93–10.47	1974-1975	0.719775	2	0.511998	21	−12.5
11.82–10.93	1971–1974	0.713703	14	0.512335	199	−5.9
12.25–11.82	1970-1971	0.709416	12	0.511623	262	−19.8
12.71–12.25	1968–1970	0.717248	13	0.512081	68	−10.9
13.16–12.71	1967-1968	0.714732	15	0.511865	203	−15.1
17.05–15.52	1952–1958	0.716986	5	0.511993	19	−12.6
18.03–17.05	1948–1952	0.712315	25	0.511908	74	−14.2
20.09–18.03	1939–1948	0.712284	26	0.512069	197	−11.1
21.12–20.09	1934–1939	0.718733	14	0.511986	25	−12.7
22.74–21.12	1926–1934	0.712936	51	0.511722	139	−17.9
23.92–22.74	1919–1926	0.720629	3	0.511957	51	−13.3
24.52–23.92	1916–1919	0.716637	20	0.512135	103	−9.8
26.18–24.52	1906–1916	0.709494	42	—	—	—
27.14–26.18	1900–1906	0.723513	7	0.511929	18	−13.8
28.38–27.14	1893–1900	0.713982	20	0.512110	40	−10.3
29.61–28.38	1884–1893	0.715272	12	0.511999	53	−12.5
30.89–29.61	1874–1884	0.719117	2	0.512011	11	−12.2
31.50–30.89	1869–1874	0.714151	21	0.511907	108	−14.3
34.04–31.50	1847–1869	0.711404	18	0.512005	55	−12.4
36.55–34.04	1821–1847	0.713235	9	0.512090	17	−10.7
38.43–36.55	1798–1821	0.711326	10	0.511911	44	−14.2
39.10–38.43	1789–1798	0.716228	15	0.511956	25	−13.3
39.62–39.26	1782–1787	0.726190	4	0.511967	8	−13.1
41.57–39.62	1751–1782	0.711900	15	0.511968	72	−13.1
42.81–41.57	1729–1751	0.712842	6	0.512382	28	−5.0
43.43–42.81	1717–1729	0.712277	20	—	—	—
44.06–43.43	1704–1717	0.710148	23	0.511809	118	−16.2
44.70–44.06	1690–1704	0.711321	16	0.511950	43	−13.4
45.33–44.70	1675–1690	0.712921	63	0.511975	53	−12.9
45.93–45.33	1660–1675	0.716865	34	0.512066	46	−11.2
46.59–45.93	1642–1660	0.715511	10	0.511990	31	−12.6
47.20–46.59	1624–1642	0.709537	15	0.512169	99	−9.1
47.81–47.20	1605–1624	0.712651	20	0.511995	66	−12.6
48.42–47.81	1585–1605	0.712811	30	0.511856	62	−15.2
49.04–48.42	1563–1585	0.715854	11	0.511964	57	−13.2
50.20–49.04	1514–1563	0.712714	37	0.512184	245	−8.9
50.62–50.20	1495–1514	0.714821	169	0.511771	43	−16.9
51.91–50.62	1427–1495	0.715864	5	0.511949	35	−13.4
54.92–53.73	1187–1300	0.717380	1	0.512051	14	−11.5
A	25.06.2008	0.710311	2	0.511958	22	−13.3
B	07.08.2008	0.713474	24	0.512088	75	−10.7
C	09.09.2008	0.710946	5	0.512012	10	−12.2
D	10.09.2008	0.710859	1	0.512042	4	−11.6
E	12.10.2009	0.710600	5	0.512063	19	−11.2
F	14.10.2009	0.710728	5	0.512008	9	−12.3
G	13.05.2009	0.710740	2	0.512088	27	−10.7
H	24.05.2009	0.710430	1	0.512064	33	−11.2
I	28.05.2008	0.709737	8	0.512040	8	−11.7
J	01.06.2008	0.710570	4	0.512057	21	−11.3
K	11.09.2008	0.711140	3	0.512018	6	−12.1
L	13.10.2008	0.712981	5	0.512036	20	−11.7

^aThe apparent age is calculated by the age model and used to plot the results. Difference between absolute and apparent ages is discussed in the text, based on ice core absolute date (e.g., Laki volcanic layer) and radiocarbon dating.
^bAll values corrected for internal mass fractionation by normalizing to ⁸⁶Sr/⁸⁸Sr = 0.1194 and for external fractionation by normalizing the measured SRM987 values to a SRM987 nominal value of 0.710248.
^cAll values corrected for internal mass fractionation by normalizing to ¹⁴⁶Nd/¹⁴⁴Nd = 0.7219 and for external fractionation by normalizing the measured Jndi-1 values to a Jndi-1 value of 0.512115 [18].
^dCalculated for a present-day CHUR value of ¹⁴³Nd/¹⁴⁴Nd = 0.512638 [19].