Table T2. Regression
equations for carbonate content estimation, Leg 172.
Site
Unit/Subunit
N
Adjusted
r2RMSE
(%)
Prediction
equation - CaCO3
(wt%)*
1054
I
63
0.994
4.99
= 380.59D465
- 9488.62(D455)2 + 494.79D435 + 844.46D655
+ 18760.06(D695)2 + 940.74D455
1055
I
91
0.990
4.02
= 1.204R490 +
384.973D445
1056
I
594
0.983
5.32
= 1.104R580
+ 418.649D445 + 3733.452(D675)2
1057
I
127
0.977
4.74
= 0.062(R610)2
- 10.930R400 + 9.994R470
1058
I
434
0.949
6.10
= 347.94D465 +
5681.51(D465)2 + 0.03(R630)2 +
304.52D575 + 15680.56(D675)2 - 22767.19(D575)2
1059
I
518
0.932
6.17
= 42.745D465
+ 0.058(R550)2 + 7417.036(D455)2
1060
I
618
0.941
4.27
= -0.043(R550)2
+ 9367.365(D435)2 + 0.093(R500)2
1061
I
421
0.950
4.32
= 0.042(R530)2
+ 13009.538(D435)2 -11604.8(D485)2
+ 199.2D405
1062
I
353
0.933
6.30
= 5965.94(D485)2
+ 0.032(R640)2 - 15748.5(D605)2
+ 7737.974(D415)2 + 192.354D405
1063
IA
629
0.944
5.27
= 5517.618(D455)2
+ 679.051D405 + 311.074D595 + 0.087(R530)2
-1.504R400 -7836.977(D405)2
All
I
3862
0.934
7.09
= 603.751D465 +
0.056(R540)2 -0.873R420
All
II
165
0.949
6.70
= 343.692D465 +
8676.303(D415)2 +766.342D515 - 6092.993(D485)2
- 2296.044(D565)2
All
III
103
0.940
6.31
= 809.884D465
- 26491.2(D585)2 + 10140.34D655
All
All
4141
0.935
7.07
= 620.267D465 +
0.0536(R540)2- - 0.855R420
Notes: N = number of samples. Adjusted r2 = adjusted correlation coefficient. RMSE = root-mean-square error. * = the following abbreviations are used for the regression terms: Rxxx = percent reflectance at xxx nm wavelength; Dyyy = the first derivative of the reflectance at yyy nm wavelength (i.e., calculated as a first difference between reflectance at [yyy + 5] nm and reflectance at [yyy - 5] nm).