SHRIMP II v2 SW v2.13 ACQUISITION DATA PRINTOUT
analyst GSWA, mount G14-21-1,
OGC-4.1, 2014-08-14, 20:36:16, set 1 of 1
6 scans, 25 nano seconds dead time, RATIO TO SBM ON, SBM zero 23557, autocenter ON, trim mass offset disabled
data reduction Zircon, BR266, spot x=7985, y=1859, z=2772
primary beam = -1.8nA
QT1 Y defl = -1729 bits; QT1 Z defl = 400 bits
runtable 2014-08-14 GSWA 0955
duration: 15min 28sec (928sec)


RUN TABLE
# Name AMU AMU Offset Time s Delay s Coll Focus Centering Ref Cent Detector CUP Mode setting
1 Zr2O 195.82440 0.00000 2.0 8.0 12 YES 3.0 REF ALW COUNTER R 1.0E-12
2 Pb204 203.98240 0.00000 10.0 3.0 11 NO 10.0 NONE ALW COUNTER  
3 Bkgrnd 204.02740 0.00000 10.0 5.0 11 NO 0.5 BAC ALW COUNTER  
4 Pb206 205.98818 0.00000 10.0 4.0 11 YES 6.0 REF ALW COUNTER R 1.0E-12
5 Pb207 206.99319 0.00000 30.0 2.0 11 NO 5.0 NONE ALW COUNTER FS+10mV=1Mcps=FIXED As
6 Pb208 207.99619 0.00000 10.0 2.0 11 NO 4.0 NONE ALW COUNTER  
7 U238 238.07372 0.00000 5.0 3.0 10 YES 3.0 REF ALW COUNTER  
8 ThO248 248.04951 0.00000 5.0 3.0 9 YES 3.0 NONE ALW COUNTER  
9 UO254 254.05629 0.00000 2.0 3.0 9 YES 2.0 REF ALW COUNTER  
AMU-B calibration field offset -0.076 G.

DATA
Zr2O 19371   19844   20476   20701   21230   22021  
Pb204 1   2   3   1   1   1  
Bkgrnd 0   0   0   0   2   3  
Pb206 25604   25025   24581   24591   24051 R 24226 R
Pb207 22405   22393   22247   21850   21978   21819  
Pb208 6926   6843   6829   6801   6634   6754  
U238 7340   7457   7548   7554   7834   7753  
ThO248 49786   49440   49724   50530   50506   51199  
UO254 20418   20072   20608   20737   20612   20701  
I - insufficient counts to center; C - fail to center; R - failed F test, passed by rejection F - failed F test, accepts all counts, S - re-measured

LINEAR REGRESSION (reject at 2 x cnt stat)
  Zr2O Pb204 Bkgrnd Pb206 Pb207 Pb208 U238 ThO248 UO254
F 1.0 0.4 0.0 2.2 0.6 0.6 0.7 2.1 2.0
slope 3.3 -0.0 0.0 -1.8 -0.8 -0.3 0.6 2.1 0.6
interc 1.9E+4 1.9E+0 -8.5E-1 2.6E+4 2.3E+4 6.9E+3 7.3E+3 4.9E+4 2.0E+4
cps 1.0E+4 1.5E-1 9.1E-2 2.5E+3 7.4E+2 6.8E+2 1.5E+3 1.0E+4 1.0E+4
rej1                  
rej2                  

RATIOS
  204/206 207/206 208/206 196/238 206/238 248/238 254/238
error +- 0.000022 0.298912 0.275920 6.881442 1.636414 6.634366 6.786066
ratio 0.000021 0.001423 0.001737 0.037742 0.009968 0.035777 0.042058

CALIBRATION
CALIBRATION Zr20/U=1.3034 Pb/U=0.2257 UO/U=6.9737 (Pb/U=0.03554(UO/U)^2)

REDUCED DATA
  rad cor +- age Ma +-  
uncorrected          
Pb206/U238 0.6935 0.0096 3395.8028 36.4  
Pb207/Pb206 0.2989 0.0014 3464.5929 7.4  
Pb207/U235 28.5802 0.4333 3439.2104 14.8  
Pb208/Th232 0.1776 0.0031 3304.6739 52.5  
204 corrected          
Pb206/U238 0.6932 0.0096 3394.8524 36.4  
Pb207/Pb206 0.2987 0.0015 3463.3548 7.6  
Pb207/U235 28.5471 0.4346 3438.0734 14.8  
Pb208/Pb206 0.2752 0.0019      
Pb208/Th232 0.1771 0.0031 3295.8080 53.1  
207 corrected          
Pb206/U238 0.6800 0.0095 3344.3604 36.4  
Pb208/Pb206 0.2373 0.0051      
Pb208/Th232 0.1498 0.0040 2821.0044 71.0  
208 corrected          
Pb206/U238 0.6964 0.0097 3407.0160 36.7  
Pb207/Pb206 0.3017 0.0021 3479.0661 10.6  
Pb207/U235 28.9712 0.4707 3452.5433 15.8  

CONCENTRATIONS
CONCENTRATIONS U:168.0 ppm Th:181.0 ppm Th/U:1.077 ±0.0 Pb204:2.2 ppb sens 16.6