Fig. 5

TEM images of Asian dust particles acquired at 200 kV using a JEOL JEM 2010 and at 80 kV using a JEOL JEM ARM 200F instruments. EDS spectra were acquired using an Oxford X-MAX detector. Asian dust was collected in Korea, 18 Mar 2014. Inset in top image of each panel is the SEM image of the dust particle obtained just before FIB work. Bottom image of each panel was magnified from the rectangular boxes in top image. EDS patterns were acquired from the circled areas. a ISCM-rich particle with goethite (Gth) inclusions. Magnified image shows compact, straight packets (CSPs, illite) of mottled strong contrast scattered through thin loose, curving packets (LCPs, smectite, interstratified illite–smectite) of weak contrast. b ISCM-rich particle with circular pore and submicron inclusions of quartz, K-feldspar, chlorite, apatite, barite, and iron oxide. Magnified image shows CSPs scattered through fine LCP matrix. c Quartz (highlighted with dashed line) coated with clays. d Alkali feldspars (perthite, intergrowth of K-feldspar and albite) coated with ISCM-rich clay. e Complex composite particle of clay and nonclay minerals. f Composite particle of clay and nonclay minerals. Ab = albite, Afs = alkali feldspars (perthite), Brt = barite, Bt = biotite, Chl = chlorite, Gth = goethite, Ilt = illite, Fo = iron oxide, Kfs = K-feldspar, OM = organic matter, Pl = plagioclase, Qz = quartz. Cc = carbon coating, Gc = gold coating, Ss = substrate (conductive carbon tape)