Sediment Color and Reflectance Record from
Ocean Drilling Program Hole 625B, Gulf of Mexico
(Marine Isotope Stage 5 Interval)

By Harry J. Dowsett

U.S. Geological Survey, 926 National Center, Reston, VA 20192

Version 1.0

[This report is preliminary and has not been reviewed for conformity with U.S. Geological Survey editorial standards (or with the North American Stratigraphic Code).  Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government.]

INTRODUCTION

Analysis of climate indicators from the North Atlantic (McManus et al., 1994), California Margin  (Poore et al., in prep.), and ice cores from Greenland (Dansgaard et al., 1993) suggest millennial scale climate variability is a component of earthıs climate system during the last interglacial period (marine oxygen isotope stage 5).  The USGS is involved in a survey of high resolution marine records covering the last interglacial period (MIS 5) to further document the variability of climate and assess the rate at which climate can change during warm intervals.

The Gulf of Mexico (GOM) is an attractive area for analysis of climate variability and rapid change.  Changes in the Mississippi River Basin presumably are translated to the GOM via the river and its effect on sediment distribution and type.  Likewise, the summer monsoon in the southwestern US is driven by strong southerly winds.  These winds may produce upwelling in the GOM which will be recorded in the sedimentary record.    Several areas of high accumulation rate have been identified in the GOM.  Ocean Drilling Program (ODP) Site 625 appears to meet the criteria of having a well preserved carbonate record and accumulation rate capable of discerning millennial scale changes.

It is not cost effective to analyze high resolution (=high accumulation rate) MIS 5 sequences in the frequency domain using traditional paleoclimate proxies (e.g., total  faunal analysis, stable isotopes).  In order to discriminate events on millennial and sub-millennial scales, sample spacing needs to be on the order of 200-300 years.  Given the duration of MIS 5 of ~60,000 years, a sample spacing of 300 years would require 200 time-intensive faunal analyses.  Instead, we have developed a strategy which uses initial analysis of physical properties measurements to document the variability of sequences.  This in turn allows us to target specific portions of sequences using fewer total faunal and stable isotopic analyses.

Physical properties measurements are routinely available for most later ODP Legs but are not available for Leg 100 (ODP625).  This report documents the development of a sediment color and reflectance record for the MIS 5 interval of ODP Hole 625B in the northeastern Gulf of Mexico and analyzes that record in the frequency domain.

MATERIALS AND METHODS

ODP Site 625 was drilled in 1985 during a shakedown cruise of the JOIDES Resolution.  Hole 625B was drilled in 889 m of water on the west Florida continental slope (28.831667°N, 87.160000°W), just south of Desoto Canyon. (FIGURE 1).
 

A 5.35 m.y.. planktonic stable isotope record was developed for Hole 625B by Joyce et al. (1990).  The stratigraphic resolution of their record is coarse (one sample every 15 cm) yet sufficient to recognize marine isotope stages and define the approximate limits of MIS 5 (FIGURE 2).  The MIS6/5 (6.0) and MIS 5/4 (5.0) boundaries were placed at 15.80 and 12.70 m sub bottom depth respectively (Martin et al., 1990).  Correlation to the SPECMAP time scale (Imbrie et al., 1984) indicates a mean accumulation rate for this interval of 5.7 cm  kyr-1.   All sample depths at Hole 625B were converted to age using the age model derived from the Joyce et al. (1990) isotopic data.
 
 

TABLE 1.  Age model for ODP 625B.

Specmap isotopic event       Age (KY)¹   Depth (m)²
4.0                                             59,000           11.70
5.0                                              71,000           12.70
6.0                                            128,000           15.80
7.0                                            186,000           17.45
¹  Imbrie et al., 1984
² Martinson et al., 1990

 
An Analytical Spectral Devices (ASD) spectroradiometer (model FS-FR) was used to make measurements of the relative spectral reflectance of sediments from sections 625B-2H-6 through 625B-2H-4.  The setup (FIGURE 3) consists of a halogen light source and fiber optic sensor connected to a spectrometer.  The tip of the fiber optic sensor is set up 2.5 cm above the split core surface.  The core is moved under the sensor at equally spaced increments.  The light that is reflected off the sediment surface is captured by the sensor and collected in the spectrometer.
 
 

A continuous spectrum of reflected light was measured from 350nm to 2500nm at 2 cm intervals between 12.40 m and 16.98 m sub bottom at ODP Hole 625B. The spectrometer was recalibrated to a white halon reference panel at the beginning of each core section. Raw data (FIGURE 4) were converted to percent reflectance and averaged in two 50-nm wide bands defined as blue (450-500nm) and red (650-700nm).  These data are plotted in FIGURE 5 and attached as APPENDIX 1.  The longer wavelengths of these spectra (reflected infrared), while commonly suitable to characterize mineral phases, were not utilized due to degradation of the spectra by the water content of the sediments.
 
 

After conversion to time using the age model described above, both red and blue band records were analyzed in the frequency domain using the ARAND³  software package.  Results are discussed below.

³The ARAND software package is available from Philip Howell, Brown University Geological Sciences, by contacting Philip_Howell@brown.edu.
 
 
 
 

DISCUSSION

Both red and blue band records show 5 strong fall-offs in reflectance over the 5 meter long record (FIGURE 5).  Two of these low reflectance peaks are associated with the 4/5 and 5/6 section breaks.  On further inspection, the other 3 low reflectance values were found to be associated with voids in the core due to removal of material by previous investigators.  These void and core break anomalies were removed prior to time series analysis.

Comparison of the reflectance records with the d18O record shows no obvious correlation (FIGURE 6).  Between ~115 Ka and 65 Ka there is a general correlation suggesting higher reflectance is associated with lighter isotopic values.  Between ~140 Ka and 115 Ka the correlation is poor but suggests the opposite, lighter isotopic values are associated with lower percent reflectance.  The limits of MIS 5, events 5.0 and 6.0 do not show up in the reflectance records. FIGURES 5 and 6 qualitatively show a regular cyclical pattern to both blue and red color reflectance records.
 

Based upon the age model developed above, the color reflectance record (2 cm sample interval) has a resolution of ~350 years.  The reflectance records show numerous rapid (<400 year duration) terminations to many of the cycles.  Both records were resampled at equal time increments of 400 years for time series analysis.  The ARAND software package was used to perform cross spectral analysis on the blue and red reflectance records (FIGURE 7).  Both records show a coherent concentration of spectral power at periodicityıs of 1900 and 2900 years.  Other higher frequency spectral peaks are ignored due to the 400 year sample spacing.

Preliminary faunal and isotopic work on portions of the MIS 5 sequence from Hole 625B show abundant fine grained material in many samples.  Although degraded so as to not allow accurate identifications, the infrared portion of the spectra identifies various clay mineralogies.  The amount and type of fine grained terrigenous material delivered to Hole 625B by rivers may account for changes in the reflectance record (see FIGURE 1).
 

SUMMARY  AND CONCLUSIONS

This report documents our ability to generate low cost physical properties measurements on deep sea cores for the purpose of determining variability in sedimentation.

Millennial scale variability within MIS 5 in the northeastern Gulf of Mexico occurs at periodicities very similar to those found in the North Atlantic, North Pacific, and ice cores.  These cycles may reflect changes in the hydrology of  that part of North America that drains into the GOM.

In order to better understand the significance and meaning of these cycles we have re-sampled 625B for isotopes and total faunal analysis at 4 cm intervals.  This will increase the resolution of the Joyce et al. (1990) isotopic record and allow comparisons between it, the color reflectance record, and the planktic foraminifer assemblages which will be used to estimate sea surface temperatures within MIS 5.

The data developed in this report (Appendix 1) are available from the USGS at
http://chht-ntsrv.er.usgs.gov/warmclimates/products.html or by contacting the author at hdowsett@usgs.gov.

ACKNOWLEDGMENTS

This paper benefited from reviews and discussions with R.Z. Poore, M. Podwysocki and S. Verardo.  I would like to thank M. Podwysocki for the time he spent instructing me on the capabilities of the spectrometer and pointing out other potential uses in paleoceanographic work.  V. Lovern assisted with the analyses and processed the spectra.  R. Martin provided the original 625B stable isotope record.  I thank the personnel of the ODP East Coast Repository for their help with sampling the core.  This work was supported by the USGS Global Change and Climate History Program.

 REFERENCES

Dansgaard, W., Johnsen, S.J., Clausen, H.B., Dahl-Jensen, D., Gundestrup, N., Hammer, C.U., Hvidberg, C.S., Steffensen, J.P., Sveinbjornsdottir, A.W., Jouzel, J. and Bond, G., 1993.  Evidence for general instability of past climate from a 250-kyr ice-core record.  Nature 364: 218-220.

Imbrie, J., Hays, J.D., Martinson, D.G., McIntyre, A., Mix, A.C., Morley, J.J., Pisias, N.G., Prell, W.L. and Shackleton, N.J., 1984. The orbital theory of Pleistocene climate:  support from a revised chronology of the marine d18O record. Berger, A.L. et al. (Eds.), Milankovitch and Climate, Part 1. D. Reidel. 269-305.

Joyce, J.E., Tjalsma, L.R.C. and Prutzman, J.M., 1990.  High-resolution planktic stable isotope record and spectral analysis for the last 5.35 My: Ocean Drilling Program Site 625 northeast Gulf of Mexico.  Paleoceanography 5(4): 507-529.

Martin, R.E., Johnson, G.W., Neff, E.D. and Krantz, D.W., 1990.  Quaternary planktonic foraminiferal assemblage zone of the northeast Gulf of Mexico, Colombia Basin (Caribbean Sea), and tropical Atlantic Ocean:  Graphic correlation of microfossil and oxygen isotope datums.  Paleoceanography 5(4): 531-555.

McManus, J.F., Bond, G.C., Broecker, W.S., Johnsen, S., Labeyrie, L. and Higgins, S., 1994.  High resolution climate records from the North Atlantic during the last interglacial.  Nature 371: 326-329.

Poore, R.Z., Dowsett, H.J., Barron, J.A., Heusser, L., Ravelo, C. and Mix, A., 2000.  Multiproxy record of the last interglacial off central and northern California, USA:  ODP Sites 1018 and 1020.  U.S. Geological survey Professional Paper1632, 19p.

APPENDIX 1

Appendix 1.  ODP625B reflectance data.
   Reflectance

spectra file depth (mbsf) Age (kyr) blue 450-500nm red 650-700nm
625B-HD.000 12.40 65.4838710 0.083335294 0.176176431
625B-HD.001 12.42 65.8516129 0.110769765 0.188504961
625B-HD.002 12.44 66.2193548 0.101746608 0.166474882
625B-HD.003 12.46 66.5870968 0.096139824 0.159800333
625B-HD.004 12.48 66.9548387 0.099861373 0.179771804
625B-HD.005 12.50 67.3225807 0.112930078 0.189696667
625B-HD.006 12.52 67.6903226 0.110420941 0.187510765
625B-HD.007 12.54 68.0580645 0.118327588 0.195456392
625B-HD.008 12.56 68.4258065 0.140480725 0.219516020
625B-HD.009 12.58 68.7935484 0.142133157 0.218877216
625B-HD.010 12.60 69.1612903 0.147841922 0.227863784
625B-HD.011 12.62 69.5290323 0.162747745 0.243939020
625B-HD.012 12.64 69.8967742 0.148193294 0.227831294
625B-HD.013 12.66 70.2645161 0.147453824 0.225008294
625B-HD.014 12.68 70.6322581 0.147754157 0.223871784
625B-HD.015 12.70 71.0000000 0.137139333 0.216899490
625B-HD.016 12.72 71.3677419 0.140181235 0.219009745
625B-HD.017 12.74 71.7354839 0.127486039 0.206241118
625B-HD.018 12.76 72.1032258 0.134490098 0.217601922
625B-HD.019 12.78 72.4709677 0.132123961 0.204860784
625B-HD.020 12.80 72.8387097 0.151023137 0.229164137
625B-HD.021 12.82 73.2064516 0.145339333 0.225980569
625B-HD.022 12.84 73.5741936 0.120837510 0.190183549
625B-HD.023 12.86 73.9419355 0.112850549 0.190106667
625B-HD.024 12.88 74.3096774 0.098343549 0.182250765
625B-HD.025 12.90 74.6774194 0.108561275 0.188949784
625B-HD.026 12.92 75.0451613 0.113414745 0.190883549
625B-HD.027 12.94 75.4129032 0.127141588 0.205825353
625B-HD.028 12.96 75.7806452 0.137218314 0.216419784
625B-HD.029 12.98 76.1483871 0.144053255 0.224230098
625B-HD.030 13.00 76.5161290 0.147166275 0.236199941
625B-HD.031 13.02 76.8838710 0.142273980 0.231035529
625B-HD.032 13.04 77.2516129 0.136238824 0.218418667
625B-HD.033 13.06 77.6193548 0.134886941 0.212004078
625B-HD.034 13.08 77.9870968 0.148723275 0.228568373
625B-HD.035 13.10 78.3548387 0.165813980 0.256792647
625B-HD.036 13.12 78.7225807 0.146680392 0.230860843
625B-HD.037 13.14 79.0903226 0.147254608 0.230206275
625B-HD.038 13.16 79.4580645 0.154067706 0.236640784
625B-HD.039 13.18 79.8258065 0.154790000 0.244709843
625B-HD.040 13.20 80.1935484 0.146210176 0.235020902
625B-HD.041 13.22 80.5612903 0.159979000 0.250582000
625B-HD.042 13.24 80.9290323 0.147552902 0.227976059
625B-HD.043 13.26 81.2967742 0.145774431 0.227788667
625B-HD.044 13.28 81.6645161 0.152288196 0.240001275
625B-HD.045 13.30 82.0322581 0.156740843 0.246789510
625B-HD.046 13.32 82.4000000 0.166318431 0.262815863
625B-HD.047 13.34 82.7677419 0.169873588 0.270999941
625B-HD.048 13.36 83.1354839 0.176872627 0.275239353
625B-HD.049 13.38 83.5032258 0.153806451 0.243200510
625B-HD.050 13.40 83.8709677 0.182956843 0.281680941
625B-HD.051 13.42 84.2387097 0.200301216 0.299665412
625B-HD.052 13.44 84.6064516 0.203133235 0.304556961
625B-HD.053 13.46 84.9741936 0.098623863 0.122014294
625B-HD.054 13.48 85.3419355 0.195206627 0.298331608
625B-HD.055 13.50 85.7096774 0.186591255 0.287151941
625B-HD.056 13.52 86.0774194 0.186366373 0.292070588
625B-HD.057 13.54 86.4451613 0.176363176 0.283638784
625B-HD.058 13.56 86.8129032 0.179112294 0.283923471
625B-HD.059 13.58 87.1806452 0.177185235 0.277674294
625B-HD.060 13.60 87.5483871 0.185481314 0.290866333
625B-HD.061 13.62 87.9161290 0.179506157 0.284272941
625B-HD.062 13.64 88.2838710 0.178623294 0.287041294
625B-HD.063 13.66 88.6516129 0.180027059 0.287152627
625B-HD.064 13.68 89.0193548 0.171827961 0.287281804
625B-HD.065 13.70 89.3870968 0.180026843 0.297545392
625B-HD.066 13.72 89.7548387 0.194651569 0.313420882
625B-HD.067 13.74 90.1225807 0.181490549 0.303637922
625B-HD.068 13.76 90.4903226 0.182052353 0.304422627
625B-HD.069 13.78 90.8580645 0.183004137 0.313175157
625B-HD.070 13.80 91.2258065 0.178089392 0.314970471
625B-HD.071 13.82 91.5935484 0.164049392 0.302158882
625B-HD.072 13.84 91.9612903 0.138170137 0.270635294
625B-HD.073 13.86 92.3290323 0.075384980 0.142855529
625B-HD.074 13.90 93.0645161 0.107071941 0.218112902
625B-HD.075 13.92 93.4322581 0.210960294 0.343915529
625B-HD.076 13.94 93.8000000 0.174139922 0.266298157
625B-HD.077 13.96 94.1677419 0.171390353 0.264451255
625B-HD.078 13.98 94.5354839 0.170414216 0.265143451
625B-HD.079 14.00 94.9032258 0.175241725 0.269624843
625B-HD.080 14.02 95.2709677 0.185831118 0.286358471
625B-HD.081 14.04 95.6387097 0.185533235 0.291834176
625B-HD.082 14.06 96.0064516 0.129549314 0.219864392
625B-HD.083 14.08 96.3741936 0.170397431 0.272915471
625B-HD.084 14.10 96.7419355 0.176213608 0.277934157
625B-HD.085 14.12 97.1096774 0.195273431 0.308801804
625B-HD.086 14.14 97.4774194 0.191077824 0.296488275
625B-HD.087 14.16 97.8451613 0.202887549 0.311752216
625B-HD.088 14.18 98.2129032 0.195481392 0.300620275
625B-HD.089 14.20 98.5806452 0.200992765 0.309502725
625B-HD.090 14.22 98.9483871 0.188740824 0.297124275
625B-HD.091 14.24 99.3161290 0.186306000 0.295616706
625B-HD.092 14.26 99.6838710 0.180000196 0.278412275
625B-HD.093 14.28 100.0516129 0.168002902 0.261598529
625B-HD.094 14.30 100.4193548 0.163703392 0.258277373
625B-HD.095 14.32 100.7870968 0.169921314 0.271739451
625B-HD.096 14.34 101.1548387 0.191313039 0.301007608
625B-HD.097 14.36 101.5225807 0.191070510 0.307914863
625B-HD.098 14.38 101.8903226 0.166149020 0.261658902
625B-HD.099 14.40 102.2580645 0.185949118 0.288619275
625B-HD.100 14.42 102.6258065 0.202406961 0.307445627
625B-HD.101 14.44 102.9935484 0.209181000 0.314157216
625B-HD.102 14.46 103.3612903 0.199256941 0.305645176
625B-HD.103 14.48 103.7290323 0.201363235 0.307359196
625B-HD.104 14.50 104.0967742 0.221747725 0.340331647
625B-HD.105 14.52 104.4645161 0.209415353 0.322086529
625B-HD.106 14.54 104.8322581 0.225823373 0.341106098
625B-HD.107 14.56 105.2000000 0.203150118 0.309048431
625B-HD.108 14.58 105.5677419 0.168138627 0.257653647
625B-HD.109 14.60 105.9354839 0.187591804 0.290308373
625B-HD.110 14.62 106.3032258 0.194478412 0.302977804
625B-HD.111 14.64 106.6709677 0.214498627 0.327794706
625B-HD.112 14.66 107.0387097 0.216369471 0.341453196
625B-HD.113 14.68 107.4064516 0.180854608 0.294259510
625B-HD.114 14.70 107.7741936 0.139756471 0.252818941
625B-HD.115 14.72 108.1419355 0.166825686 0.266768255
625B-HD.116 14.74 108.5096774 0.174584333 0.276126667
625B-HD.117 14.76 108.8774194 0.162884490 0.256975294
625B-HD.118 14.78 109.2451613 0.181387824 0.282466667
625B-HD.119 14.80 109.6129032 0.171661941 0.268379471
625B-HD.120 14.82 109.9806452 0.200455412 0.316291902
625B-HD.121 14.84 110.3483871 0.168561647 0.268188961
625B-HD.122 14.86 110.7161290 0.166367922 0.266227686
625B-HD.123 14.88 111.0838710 0.099984882 0.164295275
625B-HD.124 14.90 111.4516129 0.138430647 0.222866353
625B-HD.125 14.92 111.8193548 0.173149451 0.281937745
625B-HD.126 14.94 112.1870968 0.176990294 0.285307314
625B-HD.127 14.96 112.5548387 0.189978000 0.304351882
625B-HD.128 14.98 112.9225807 0.179965098 0.293142314
625B-HD.129 15.00 113.2903226 0.162770725 0.257645882
625B-HD.130 15.02 113.6580645 0.180931529 0.287537784
625B-HD.131 15.04 114.0258065 0.180256922 0.281693765
625B-HD.132 15.06 114.3935484 0.177044765 0.283768294
625B-HD.133 15.08 114.7612903 0.170005373 0.283394686
625B-HD.134 15.10 115.1290323 0.180860314 0.290254412
625B-HD.135 15.12 115.4967742 0.180635824 0.291231137
625B-HD.136 15.14 115.8645161 0.179559255 0.290588392
625B-HD.137 15.16 116.2322581 0.161014627 0.265817353
625B-HD.138 15.18 116.6000000 0.155946608 0.261555863
625B-HD.139 15.20 116.9677419 0.169038373 0.282225471
625B-HD.140 15.22 117.3354839 0.163349039 0.202534529
625B-HD.141 15.24 117.7032258 0.119357059 0.194098235
625B-HD.142 15.26 118.0709677 0.156870804 0.274664412
625B-HD.143 15.28 118.4387097 0.153023765 0.266074784
625B-HD.144 15.30 118.8064516 0.133500353 0.235724961
625B-HD.145 15.32 119.1741936 0.155981784 0.271612059
625B-HD.146 15.34 119.5419355 0.179894216 0.309459784
625B-HD.147 15.36 119.9096774 0.144369000 0.257414922
625B-HD.148 15.40 120.6451613 0.060235216 0.136974314
625B-HD.149 15.42 121.0129032 0.118228725 0.239954922
625B-HD.150 15.44 121.3806452 0.120821157 0.239958235
625B-HD.151 15.46 121.7483871 0.132712471 0.263187843
625B-HD.152 15.48 122.1161290 0.147170647 0.268280725
625B-HD.153 15.50 122.4838710 0.158342784 0.284901196
625B-HD.154 15.52 122.8516129 0.154187039 0.280031314
625B-HD.155 15.54 123.2193548 0.162822647 0.286105647
625B-HD.156 15.56 123.5870968 0.148006314 0.264971882
625B-HD.157 15.58 123.9548387 0.152548863 0.262333902
625B-HD.158 15.60 124.3225807 0.126726098 0.235330392
625B-HD.159 15.62 124.6903226 0.117016176 0.214242255
625B-HD.160 15.64 125.0580645 0.149855686 0.263619471
625B-HD.161 15.66 125.4258065 0.152803176 0.268041137
625B-HD.162 15.68 125.7935484 0.156976098 0.269520647
625B-HD.163 15.70 126.1612903 0.138988549 0.252880353
625B-HD.164 15.72 126.5290323 0.145087941 0.256482588
625B-HD.165 15.74 126.8967742 0.143479118 0.252889059
625B-HD.166 15.76 127.2645161 0.148806216 0.257483078
625B-HD.167 15.78 127.6322581 0.156314510 0.267790235
625B-HD.168 15.80 128.0000000 0.160632137 0.267652373
625B-HD.169 15.82 128.3677419 0.153868784 0.264214765
625B-HD.170 15.84 128.7354839 0.146430902 0.258606902
625B-HD.171 15.86 129.1032258 0.153133745 0.264606039
625B-HD.172 15.88 129.4709677 0.144743902 0.260384392
625B-HD.173 15.90 129.8387097 0.148293137 0.263707333
625B-HD.174 15.92 130.2064516 0.177257451 0.300318020
625B-HD.175 15.94 130.5741936 0.188598882 0.302718039
625B-HD.176 15.96 130.9419355 0.189731137 0.318418588
625B-HD.177 15.98 131.3096774 0.164786235 0.271593275
625B-HD.178 16.00 131.6774194 0.158620706 0.270987667
625B-HD.179 16.02 132.0451613 0.153830490 0.266830706
625B-HD.180 16.04 132.4129032 0.153787431 0.263874196
625B-HD.181 16.06 132.7806452 0.153658431 0.260933608
625B-HD.182 16.08 133.1483871 0.160835255 0.273768941
625B-HD.183 16.10 133.5161290 0.170924608 0.282902784
625B-HD.184 16.12 133.8838710 0.155675745 0.262244706
625B-HD.185 16.14 134.2516129 0.149432902 0.252199608
625B-HD.186 16.16 134.6193548 0.150594725 0.252412941
625B-HD.187 16.18 134.9870968 0.145941843 0.250213333
625B-HD.188 16.20 135.3548387 0.137025784 0.231326216
625B-HD.189 16.22 135.7225807 0.154157804 0.256671196
625B-HD.190 16.24 136.0903226 0.145836784 0.246860020
625B-HD.191 16.26 136.4580645 0.146153902 0.245918059
625B-HD.192 16.28 136.8258065 0.140947157 0.240663647
625B-HD.193 16.30 137.1935484 0.149101294 0.254192706
625B-HD.194 16.32 137.5612903 0.153024059 0.257920706
625B-HD.195 16.34 137.9290323 0.155655745 0.262427882
625B-HD.196 16.36 138.2967742 0.147510137 0.258327431
625B-HD.197 16.38 138.6645161 0.165944980 0.272655039
625B-HD.198 16.40 139.0322581 0.193526627 0.309527784
625B-HD.199 16.42 139.4000000 0.180239314 0.294777627
625B-HD.200 16.44 139.7677419 0.165990804 0.277752490
625B-HD.201 16.46 140.1354839 0.163186745 0.270714471
625B-HD.202 16.48 140.5032258 0.178336784 0.297609529
625B-HD.203 16.50 140.8709677 0.154184098 0.256402157
625B-HD.204 16.52 141.2387097 0.152941765 0.267598549
625B-HD.205 16.54 141.6064516 0.146090569 0.257531686
625B-HD.206 16.56 141.9741936 0.163199647 0.280948804
625B-HD.207 16.58 142.3419355 0.150292510 0.266925392
625B-HD.208 16.60 142.7096774 0.158453569 0.270686863
625B-HD.209 16.62 143.0774194 0.155883627 0.267052078
625B-HD.210 16.64 143.4451613 0.158620333 0.280817176
625B-HD.211 16.66 143.8129032 0.155672275 0.274565333
625B-HD.212 16.68 144.1806452 0.154715275 0.275259392
625B-HD.213 16.70 144.5483871 0.157154627 0.276971000
625B-HD.214 16.72 144.9161290 0.166629588 0.321575451
625B-HD.215 16.74 145.2838710 0.065423471 0.098576667
625B-HD.216 16.76 145.6516129 0.148957824 0.260457686
625B-HD.217 16.78 146.0193548 0.146772569 0.254055902
625B-HD.218 16.80 146.3870968 0.136586490 0.260606353
625B-HD.219 16.82 146.7548387 0.121558922 0.246775863
625B-HD.220 16.84 147.1225807 0.127609941 0.257506961
625B-HD.221 16.86 147.4903226 0.122718059 0.256318941
625B-HD.222 16.88 147.8580645 0.111984588 0.253518451
625B-HD.223 16.90 148.2258065 0.102085137 0.226738510
625B-HD.224 16.92 148.5935484 0.091386490 0.200657373
625B-HD.225 16.94 148.9612903 0.121032745 0.259068922
625B-HD.226 16.96 149.3290323 0.155236235 0.320076980
625B-HD.227 16.98 149.6967742 0.111796471 0.233153392

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