Table 1.   Chemistry of Izu-Bonin-Mariana Fluids
Island 	Sample Location 	Sample ID 	Latitude (°N) 	Longitude (°E) 	Sampling Date 	Sample Typea 	Temperature (°C) 	pH 	H2Ob 	CO2 	St 	SO2 	H2S 	HClc 	HFd 	NH3 	Ar 	N2 	He 	H2 	O2 	CH4 	CO 	d15N (‰)
Hakone 	Sounjigoku Fumarole Field 	Sou-1 	35 14.492' 	139 01.925' 	8/5/2005 	F 	96.1 	5.5 	990.61 	516.46 	432.29 	64.36 	366.36 	0.989 	0.188 	0.057 	0.069 	14.085 	<0.00048 	34.915 	<0.004 	0.949 	<0.00012 	5.5 ± 0.5
  	  	Sou-2 	35 14.492' 	139 01.925' 	8/5/2005 	F 	96.1 	5.5 	992.82 	522.56 	436.41 	63.28 	371.54 	3.021 	0.348 	0.202 	0.053 	11.102 	<0.00064 	25.713 	<0.005 	0.585 	<0.00016 	3.5 ± 0.6
  	Owakdani Fumarole Field 	Owa-1 	35 14.488' 	139 01.230' 	8/5/2005 	F 	96.5 	5.5 	992.95 	613.05 	341.42 	49.52 	290.65 	10.471 	0.531 	0.244 	0.073 	14.593 	<0.00046 	19.509 	<0.004 	0.106 	<0.00012 	3.0 ± 0.5
  	Yunohanazawa Fumarole Field 	Noh-1 	35 13.442' 	139 01.948' 	8/5/2005 	F 	95.8 	5.0 	996.59 	698.32 	219.71 	91.87 	127.23 	6.279 	0.687 	0.679 	0.604 	66.998 	<0.00229 	5.754 	<0.019 	0.943 	<0.00057 	-1.4 ± 0.02
Oshima 	Ohtsu Well 	Oht-1 	34 45.581' 	139 21.358' 	7/21/2005 	G+W 	36.4 	6.7 	  	902.26 	55.35 	35.41 	19.83 	  	9.608 	0.725 	0.490e 	20.993 	<0.00258 	0.011 	10.558 	<0.001 	<0.00068 	0.0 ± 0.1
  	Koshimizu Well 	Kos-1 	34 45.521' 	139 21.704' 	7/21/2005 	G+W 	48.5 	6.7 	  	881.82 	71.69 	62.14 	9.45 	  	10.300 	0.809 	0.588e 	25.399 	<0.00298 	0.010 	9.380 	<0.001 	<0.00077 	-0.6 ± 0.1
  	Univ. of Tokyo Obs. Well 	Uto-1 	34 45.243' 	139 24.125' 	7/22/2005 	G 	81.0 	4.0 	744.81 	521.88 	1.13 	  	1.13 	10.320 	1.467 	1.105 	4.661e 	384.388 	<0.00591 	0.026 	75.020 	<0.001 	<0.00143 	0.9 ± 0.05
  	  	Uto-2 	34 45.243' 	139 24.125' 	7/22/2005 	G 	81.0 	4.0 	416.51 	344.06 	0.48 	  	0.48 	4.202 	0.346 	0.201 	6.529e 	540.343 	<0.00359 	0.019 	103.814 	<0.001 	<0.00086 	0.9 ± 0.1
  	Hotel Onsen Well 	Ons-1 	34 45.213' 	139 24.231' 	7/22/2005 	G+W 	84.9 	6.7 	  	965.75 	12.76 	  	12.76 	  	3.316 	1.364 	0.289e 	12.368 	<0.00227 	0.126 	3.918 	0.108 	<0.00059 	-2.5 ± 0.1
  	  	Ons-2 	34 45.213' 	139 24.231' 	7/22/2005 	G+W 	84.9 	6.7 	  	944.52 	17.43 	  	17.43 	  	2.582 	2.256 	0.472e 	20.788 	<0.00739 	0.277 	11.425 	0.237 	<0.00184 	-2.2 ± 0.2
Niijima 	Mamashita Hot Spring Well 	Mam-1 	34 21.670' 	139 14.699' 	7/20/2005 	G+W 	62.0 	7.0 	  	737.05 	218.56 	  	218.56 	  	8.676 	0.643 	0.711e 	30.804 	<0.00284 	0.009 	3.542 	<0.001 	<0.00073 	-0.3 ± 0.2
  	  	Mam-2 	34 21.670' 	139 14.699' 	7/20/2005 	G+W 	62.0 	7.0 	  	804.36 	185.05 	167.34 	17.47 	  	n.m. 	0.099 	0.250e 	9.421 	<0.00310 	0.004 	0.809 	0.001 	<0.00014 	0.6 ± 0.2
Shikinejima 	Jinata Hot Springs 	Jin-1 	34 19.128' 	139 12.882' 	7/19/2005 	BS 	66.2 	7.0 	771.05 	908.89 	1.26 	  	1.26 	29.641 	0.156 	0.583 	0.707e 	58.190 	0.02495 	0.004 	0.401 	0.140 	<0.00028 	1.6 ± 0.2
  	  	Jin-2 	34 19.128' 	139 12.882' 	7/19/2005 	BS 	66.2 	7.0 	705.65 	827.10 	0.78 	  	0.78 	19.005 	0.127 	0.068 	1.765 	150.058 	0.06408 	0.006 	0.679 	0.348 	<0.00025 	2.0 ± 0.2
Hachijojima 	Sueyoshi Hot Spring Well 	Sue-1 	33 04.889' 	139 50.985' 	8/2/2005 	G+W 	43.9 	8.0 	  	787.87 	144.55 	  	144.55 	  	n.m. 	0.830 	0.713 	65.985 	<0.00293 	0.014 	<0.025 	0.012 	<0.00078 	-0.1 ± 0.1
  	Kashidate Hot Spring Well 	Kas-1 	33 04.562' 	139 47.423' 	8/2/2005 	G+W 	44.6 	7.0 	  	926.15 	61.06 	  	61.06 	  	n.m. 	0.081 	0.290e 	12.243 	<0.00095 	0.004 	0.168 	0.007 	<0.00026 	0.1 ± 0.1
  	Geothermal Power Plant 	Geo-1 	33 04.494' 	139 48.742' 	8/3/2005 	G 	170.8 	5.5 	990.76 	864.94 	121.56 	42.69 	78.51 	1.363 	0.356 	0.051 	0.005 	1.311 	0.00108 	10.389 	<0.003 	0.022 	<0.00008 	4.8 ± 0.1
  	  	Geo-2 	33 04.494' 	139 48.742' 	8/3/2005 	G 	170.8 	5.5 	990.68 	820.18 	107.56 	63.46 	43.86 	2.292 	0.254 	1.438 	0.263 	46.598 	<0.00100 	21.318 	0.048 	0.043 	0.00354 	3.0 ± 0.1
  	Ogoshi Hot Spring Well 	Ogo-1 	33 03.830' 	139 49.002' 	8/2/2005 	G+W 	53.3 	7.5 	  	918.30 	47.50 	  	47.50 	  	1.365 	0.576 	0.692e 	29.041 	<0.00176 	0.044 	2.407 	0.069 	<0.00048 	1.9 ± 0.1
  	Yasuragi Hot Spring Well 	Yas-1 	33 03.623' 	139 48.894' 	8/2/2005 	G+W 	54.4 	6.5 	  	854.43 	118.30 	113.23 	4.94 	  	4.418 	0.783 	0.510e 	20.790 	0.00729 	0.008 	0.709 	0.040 	<0.00033 	0.3 ± 0.1
Aogashima 	Funakoyama Fumarole Field 	Aog-3 	32 27.435' 	139 45.717' 	7/29/2005 	F 	99.4 	5.0 	996.20 	861.86 	0.55 	  	0.55 	3.219 	0.768 	0.945 	1.240e 	101.333 	0.01419 	1.179 	27.863 	1.028 	<0.00054 	-2.5 ± 0.1
  	  	Aog-3a 	32 27.435' 	139 45.717' 	7/29/2005 	F 	99.4 	5.0 	996.78 	835.46 	0.68 	  	0.68 	12.116 	1.764 	0.711 	1.379e 	112.425 	0.01744 	1.304 	33.068 	1.074 	<0.00049 	-2.1 ± 0.1
  	Maruyama Volcano Central Cone 	Aog-1 	32 27.182' 	139 45.915' 	7/29/2005 	F 	85.8 	5.3 	898.22 	504.56 	1.27 	  	1.27 	10.633 	1.256 	3.457 	4.679e 	386.547 	<0.00881 	0.023 	87.562 	<0.002 	<0.00213 	1.3 ± 0.1
  	Misone Fumarole Field 	Aog-2 	32 27.136' 	139 45.735' 	7/29/2005 	F 	99.2 	5.0 	986.79 	965.52 	6.31 	  	6.31 	0.862 	0.193 	0.090 	0.138 	22.745 	0.01052 	3.388 	0.011 	0.733 	<0.00008 	1.6 ± 0.2
  	  	Aog-2a 	32 27.136' 	139 45.735' 	7/29/2005 	F 	99.2 	5.0 	988.68 	961.54 	6.90 	2.64 	4.23 	3.585 	1.141 	0.199 	0.131 	21.611 	0.01255 	3.963 	<0.004 	0.916 	<0.00013 	1.3 ± 0.1
Pagan 	Old Crater 	Mar-3 	18 04.265' 	145 43.487' 	4/18/2004 	F 	96.1 	5.0 	964.18 	942.84 	8.11 	  	8.11 	2.218 	0.005 	0.031 	0.398 	35.362 	0.00466 	4.109 	6.873 	0.049 	<0.00010 	0.7 ± 0.2
  	  	Mar-9 	18 04.265' 	145 43.487' 	4/18/2004 	F 	96.1 	5.0 	949.37 	972.56 	9.07 	  	9.07 	2.527 	0.005 	0.016 	0.013 	9.730 	0.00388 	4.918 	1.105 	0.056 	<0.00023 	1.6 ± 0.4
Agrigan 	Summit Crater 	Mar-7 	18 46.694' 	145 40.282 	4/21/2004 	F 	98.0 	3.0 	957.91 	937.05 	56.02 	11.07 	44.76 	2.501 	0.005 	0.018 	0.038 	2.812 	0.01332 	1.516 	0.015 	0.011 	0.00323 	-2.7 ± 0.3
  	  	Mar-8 	18 46.694' 	145 40.282 	4/21/2004 	F 	98.0 	3.0 	890.19 	883.17 	109.20 	  	109.20 	4.796 	0.003 	0.006 	0.029 	1.874 	0.00763 	0.905 	0.003 	0.007 	0.00141 	-2.5 ± 0.5
aSample types: F, fumarole; G+W, geothermal well plus excess water; G, geothermal well; BS, bubbling spring.
bH2O reported as mmol/mol total gas; all other species as mmol/mol dry gas.
cValues not reported for samples containing excess water from the sampling well.
dn.m., not measured.
eIndicates a corrected value on the basis of [N2].