Table A2. Closest matches to mean composition of volcanic glass from Blind Slough sample AB-4-29-98-1(1) T408-3.

Sample Lab No. Field Number Date SiO2 Al2O3 Fe2O3 MgO MnO CaO TiO2 Na2O K2O Total,R Sim. Co  
1
 4438 AB-4-29-98-1(1) T408-3 5/30/1999 74.65 14.32 1.76 0.30 0.04 1.66 0.21 4.76 2.31 100.01 1.0000 Blind Slough, OR - A. Bordeau
2
 420 WnSH, T5-5 not reported 74.85 14.18 1.76 0.29 0.04 1.69 0.20 4.65 2.33 99.99 0.9821 Mount St. Helens, WA type
3
 4595 CL4-11/18/98-2(1)A T437-4 3/2/2000 75.10 14.11 1.76 0.31 0.04 1.65 0.20 4.58 2.26 100.01 0.9792 Wapato, WA - Port. Main mode. A. Bordeau
4
 419 Wn-7-10-72-10 not reported 74.72 14.42 1.74 0.29 0.06 1.56 0.21 4.56 2.43 99.99 0.9745 Mount St. Helens, WA - type
5
 417 Wn2SH, T8-14 not reported 74.81 14.72 1.63 0.31 0.03 1.58 0.21 4.38 2.33 100.00 0.9660 Mount St. Helens, WA - type (middle)
6
 418 Wn3SH, T8-15 not reported 74.68 14.68 1.64 0.29 0.05 1.55 0.20 4.58 2.33 100.00 0.9642 Mount St. Helens, WA, type (top)
7
 416 Wn1SH, T8-13 not reported 75.47 14.26 1.76 0.31 0.02 1.63 0.19 4.07 2.28 99.99 0.9602 Mount St. Helens, WA - type (base)
8
 3076 ST HELENS Wn T5-5 8/5/1993 75.19 14.49 1.70 0.31 0.03 1.62 0.19 4.17 2.30 100.00 0.9584 Mount St. Helens, WA - type
9
 4554 JEO_5-14-98-1(1) T432-2 not reported 74.58 14.36 1.77 0.34 0.04 1.60 0.25 4.80 2.27 100.01 0.9564  
10
 2688 RM-RC-3 T243-3 11/13/1991 74.79 14.08 1.75 0.28 0.04 1.62 0.26 4.90 2.27 99.99 0.9558  
11
 4451 JEO_10-1-98-2(1) T410-4 6/22/1999 74.87 13.85 1.76 0.31 0.05 1.54 0.24 4.87 2.50 99.99 0.9545 Mt. Jefferson, OR - pumice, ~80 ka(?)
12
 1009 SD 1490-1 T74-3 5/30/1984 74.85 14.08 1.79 0.32 0.05 1.54 0.24 4.68 2.44 99.99 0.9542 Mt. Jefferson, OR - pumice, type ~80 ka(?)
13
 510 CL-0437(200-325), T63-10 9/7/1983 75.38 13.89 1.66 0.29 0.05 1.39 0.22 4.84 2.28 100.00 0.9541  
14
 4870 JEO6/6/1(1) HiCa T474-7 1/30/2002 75.85 13.81 1.38 0.30 0.02 1.56 0.21 4.54 2.32 99.99 0.9527  
15
 4566 45CL1_SPEC1_#33,006 T434-1 1/25/2000 75.18 14.26 1.73 0.30 0.05 1.56 0.18 4.29 2.44 99.99 0.9521  
16
 4575 45CL1 spec1#33,006 T434-1 Feb-00 75.18 14.26 1.73 0.30 0.05 1.56 0.18 4.29 2.44 99.99 0.9521  
17
 4439 AB-5-15-98-2(5) T408-4 5/30/1999 74.30 14.64 1.55 0.26 0.04 1.78 0.21 4.86 2.35 99.99 0.9520  
18
 1645 AA-20a JOD 9/12/1986 75.01 13.96 1.69 0.31 0.05 1.48 0.24 4.88 2.37 99.99 0.9518  
19
 4440 AB-828-98-2(2) T408-5 5/30/1999 74.82 14.03 1.65 0.33 0.04 1.68 0.25 4.79 2.40 99.99 0.9510  
20
 4367 970911-2 T398-7 10/21/1998 74.88 13.78 1.87 0.34 0.04 1.60 0.23 4.82 2.45 100.01 0.9488  
21
 509 CL-0437(100-200), T60-6 8/16/1983 75.12 14.01 1.67 0.31 0.05 1.37 0.23 4.90 2.34 100.00 0.9482  
22
 3810 JEO 10/09/96-2 (1-D) T351-10 Dec-96 75.10 13.76 1.72 0.32 0.04 1.53 0.24 4.74 2.54 99.99 0.9465  
23
 1590 JOD SL 20 9/11/1986 75.24 13.84 1.67 0.31 0.07 1.46 0.25 4.80 2.35 99.99 0.9462  
24
 1644 AA-20 JOD 9/12/1986 75.24 13.84 1.67 0.31 0.07 1.46 0.25 4.80 2.35 99.99 0.9462  
25
 1470 ARCO A2-8 T117-1 3/6/1986 74.98 13.78 1.79 0.31 0.05 1.54 0.26 4.77 2.52 100.00 0.9449  
26
 4363 SD-1490-2(1,2,3) T398-2 10/21/1998 74.92 13.74 1.84 0.32 0.06 1.55 0.25 4.90 2.42 100.00 0.9437  
27
 4763 SL-AS7-2iii T467-2 7/23/2001 74.82 14.05 1.71 0.32 0.06 1.47 0.26 4.97 2.34 100.00 0.9408  
28
 4458 JEO_716-98-2(2)_POP2 T411-2 6/22/1999 74.59 14.06 1.86 0.32 0.06 1.48 0.25 5.02 2.37 100.01 0.9399  
29
 2689 RM-RC-4 T243-4 11/13/1991 75.15 13.85 1.73 0.26 0.04 1.62 0.28 4.79 2.28 100.00 0.9396  
30
 4453 JEO_10-1-982(2) T410-6 6/22/1999 74.56 13.93 1.81 0.31 0.05 1.55 0.26 5.01 2.53 100.01 0.9395  
31
 1646 AA-20b JOD 9/12/1986 75.21 13.81 1.65 0.29 0.06 1.40 0.24 4.98 2.37 100.01 0.9387  
32
 414 WeSH(2), T5-10 not reported 75.31 13.97 1.66 0.24 0.03 1.53 0.22 4.61 2.42 99.99 0.9387 Mount St. Helens, WA - type
33
 4452 JEO_10-1-98-2(3)B T410-5 6/22/1998 74.60 13.89 1.77 0.32 0.06 1.57 0.27 5.02 2.50 100.00 0.9371  
34
 4861 JEO 6/6/1_(1) T474-7 1/30/2002 75.97 13.71 1.38 0.29 0.02 1.51 0.22 4.55 2.35 100.00 0.9367  
35
 4461 JEO_9-30-98-3(1)A T410-8 6/22/1999 74.44 14.01 2.03 0.33 0.05 1.69 0.25 5.00 2.20 100.00 0.9348  
36
 4944 JEO10/18/01-2(1) T487-6 10/26/2002 75.97 13.87 1.45 0.34 0.04 1.58 0.21 4.42 2.12 100.00 0.9319  
37
 3011 CARP-1 T279-1 5/26/1993 75.68 13.87 1.40 0.34 0.04 1.47 0.22 4.67 2.32 100.01 0.9312  
38
 45 CARL-2(1), T8-5 not reported 74.41 14.59 1.84 0.28 0.05 1.28 0.24 4.91 2.40 100.00 0.9308  
39
 4456 JEO_10-8-98-1(1) T410-9 6/22/1999 74.82 13.78 1.73 0.30 0.03 1.49 0.28 5.01 2.57 100.01 0.9299  
40
 4106 CDGD-8 t376 1/30/1998 73.93 14.27 2.02 0.33 0.06 1.56 0.25 5.18 2.39 99.99 0.9291  
41
 4926 PLW8/01/01D2 T483-10 10/26/2002 74.56 14.59 1.75 0.33 0.04 1.74 0.16 4.31 2.51 99.99 0.9282  
42
 1648 AA-20d JOD 9/12/1986 75.39 13.64 1.58 0.29 0.05 1.40 0.24 4.91 2.49 99.99 0.9278  
43
 1749 RD-2 T141-15 5/27/1987 74.84 14.13 1.85 0.28 0.08 1.31 0.26 4.92 2.34 100.01 0.9275  
44
 501 CARL-2(3), T63-5 not reported 75.07 13.96 1.84 0.26 0.09 1.27 0.23 4.90 2.37 99.99 0.9271  
45
 2690 RM-RC-5 T243-5 11/13/1991 75.30 13.80 1.60 0.23 0.03 1.60 0.25 4.87 2.32 100.00 0.9260  

Data from the U.S. Geological Survey tephrochronology project in Menlo Park, California.
Correlations by Andrei M. Sarna-Wojcicki