Microanalysis and mineralogy of Asian and Saharan dust

Journal of Analytical Science and Technology

Table 1 Mineral compositions of Asian dust measured by SEM–EDS single-particle and X-ray diffraction analyses (wt%^a)

Sample	Qz^b	PI(Ab)	Kfs	ISCMs	Bt	Chl	Kln	Plg	Amp	Cal	Dol	Gp	Fe	Ti	Total clay minerals^c
Asian dust^d
SEM–EDS
18 Mar 2014 (n = 1096)	18.8	10.7(8.9)^e	3.6	51.0	0.9	2.7	1.1	0.0	0.8	7.8	0.9	0.4	0.5	0.9	55.7
22–23 Feb 2015 (n = 894)^f	18.8	8.9(8.4)	3.2	52.8	3.0	3.0	2.2	0.0	0.4	4.8	0.3	1.8	0.6	0.2	61.0
6–7 Mar 2016 (n = 824)	16.4	7.5(6.5)	2.5	47.6	1.2	5.4	2.3	0.0	0.7	10.3	2.6	2.3	1.0	0.2	56.5
6–7 May 2017 (n = 470)	18.0	10.9(7.4)	3.4	37.5	3.0	6.8	3.3	0.0	0.2	9.3	0.6	2.4	2.8	1.6	50.6
6–7 April 2018 (n = 493)	20.8	9.5(7.6)	4.3	48.5	1.0	4.5	1.5	0.0	1.0	5.4	0.9	1.8	0.3	0.5	55.5
XRD
18 Mar 2014	17.9	12.3	6.1	47.5	–^g	3.8	1.3	0.0	1.9	5.5	0.6	3.0	–	–	52.6
22–23 Feb 2015	19.7	10.4	4.2	51.5	–	3.7	2.6	0.0	0.7	3.8	0.3	2.1	–	–	57.8
6–7 Mar 2016	17.4	9.9	4.5	47.4	–	2.8	2.7	0.0	1.2	6.2	1.5	6.4	–	–	53.0
6–7 May 2017	19.9	10.5	4.0	41.3	–	4.4	2.0	0.0	3.8	8.5	2.4	3.3	–	–	47.7
6–7 April 2018	19.0	10.6	6.1	46.4	–	4.8	1.3	0.0	3.0	3.8	1.3	3.6	–	–	52.5
Avg. 25 Asian dusts	20.6	12.4	5.1	42.1	–	4.0	2.1	0.0	1.9	5.1	1.5	5.0	–	–	48.2
Saharan dust
SEM–EDS
15 July 2005 (n = 1622)^h	10.1	2.7(1.8)	2.1	68.0^j	0.2	1.0	10.9	–	0.1	1.5	0.4	0.7	1.1	1.1	80.1
29 Feb 2008 (n = 612)ⁱ	11.5	1.9(1.7)	1.9	60.6^j	0.3	1.1	7.1	–	0.0	9.2	1.6	4.0	0.3	0.4	69.1
XRD^k
28–31 Dec 2007	8.8	5.3	1.4	53.4	–	4.8	8.1	4.6	0.0	3.9	1.0	6.1	–	–	70.9
18–23 Jan 2008	12.1	5.5	2.0	50.6	-	4.4	11.0	4.2	0.0	3.0	1.0	4.0	–	–	70.2

^aNumber % obtained by SEM single-particle analyses was converted to weight % on the basis of available data of mineral density
^bQz = quartz, Pl = plagioclase, Ab = albite, Kfs = K-feldspar, ISCM = illite–smectite series clay minerals including illite, smectite, and illite–smectite mixed layers, Bt = biotite, Chl = chlorite, Kln = kaolinite, Plg = palygorskite, Amp = amphibole, Cal = calcite, Dol = dolomite, Gp = gypsum, Fe = iron oxides, Ti = titanium oxides. ^cTotal clay minerals: sum of ISCM, biotite, chlorite, and kaolinite
^dData from Jeong et al. (2020) with the addition of biotite, iron oxides, and titanium oxides. ^eAlbite content in parentesis
^fIn Table 2 of Jeong (2020), D18 under title 'Mineral compositions by SEM single-particle analysis' should be repaced by D17
^gNot determined
^hJeong et al. (2016) with the addition of biotite, iron oxides, and titanium oxides. ⁱUnpublished data of the author
^jThe higher contents of ISCM in comparison with XRD data are due to palygorskite-bearing samples counted as ISCMs. ^kJeong and Achterberg (2014). Samples were reanalyzed considering palygorskite content and kaolinite crystallinity