GERM Reservoir Database
Development and Maintenance by the EarthRef.org Database Team

	GERM Database Search Results   Save as ... ================== Excel spreadsheet Tab delimited text file   Sort by ... =========== Reservoir Z Element Value Median SD Low High N Unit Reference =========== Default   Units ... ======= ppm ppb ppt wt% wt%ox ======= Default   Reservoir Z Element Value Median SD Low High N Unit Info Reference Source(s) Active Continental Rifts 73 Ta 1.3           ppm Rudnick & Fountain 1995 Active Continental Rifts 73 Ta 0.7           ppm Rudnick & Fountain 1995 Alaska Trench 73 Ta 0.522           ppm Plank & Langmuir 1998 Aleutian Basalts 73 Ta 0.25         12 ppm Kelemen et al. 2004 Aleutian Trench 73 Ta 0.545           ppm Plank & Langmuir 1998 Amphibolites 73 Ta 0.41         189 ppm Gao et al. 1998 Andaman Trench 73 Ta 0.714           ppm Plank & Langmuir 1998 Andes Basalt 73 Ta 0.99         20 ppm Kelemen et al. 2004 Andesites 73 Ta 0.5           ppm Condie 1993 Andesites 73 Ta 0.53           ppm Condie 1993 Andesites 73 Ta 0.25         20 ppm Kelemen et al. 2004 Andesites 73 Ta 0.5           ppm Condie 1993 Andesites 73 Ta 0.4           ppm Condie 1993 Andesites 73 Ta 0.5           ppm Condie 1993 Andesites 73 Ta 0.35           ppm Condie 1993 Andesites 73 Ta 0.5           ppm Condie 1993 Andesites 73 Ta 0.292         50 ppm Plank & Langmuir 1998 Plank & Langmuir 1988 Archean Terrains 73 Ta 0.6           ppm Rudnick & Fountain 1995 Arenaceous Rocks 73 Ta 0.88         2754 ppm Gao et al. 1998 Arenaceous Rocks 73 Ta 0.81         121 ppm Gao et al. 1998 Ashy Clay 73 Ta 0.299         4 ppm Plank & Langmuir 1998 Australian Granite 73 Ta 2.9           ppm Kemp & Hawkesworth 2004 Collins et al. 1982 Australian Granite 73 Ta 0.88         8 ppm Kemp & Hawkesworth 2004 Whalen 1985 Basalts 73 Ta 0.24           ppm Condie 1993 Basalts 73 Ta 2.48         6 ppm Farmer 2004 Turner et al. 1996a Basalts 73 Ta 7.36         16 ppm Farmer 2004 Rogers et al. 1998 Basalts 73 Ta 0.45         12 ppm Farmer 2004 Dungan et al. 1986 Basalts 73 Ta 0.3           ppm Condie 1993 Basalts 73 Ta 0.27           ppm Condie 1993 Basalts 73 Ta 0.23           ppm Condie 1993 Basalts 73 Ta 0.25           ppm Condie 1993 Basalts 73 Ta 0.25           ppm Condie 1993 Basalts 73 Ta 0.3           ppm Condie 1993 Basalts 73 Ta 0.88         10 ppm Farmer 2004 Chung et al. 2001 Basalts 73 Ta 0.3         7 ppm Farmer 2004 Conticelli et al. 1997 Basalts 73 Ta 0.62         27 ppm Farmer 2004 Farmer et al. 2002 Basalts 73 Ta 4         3 ppm Farmer 2004 Chung et al. 1995 Basalts 73 Ta 2.64         9 ppm Farmer 2004 Hoang & Flower 1998 Basalts 73 Ta 4.19         4 ppm Farmer 2004 Chung 1999 Basalts 73 Ta 1.24         13 ppm Farmer 2004 Robert et al. 1992 Basalts 73 Ta 3.77         8 ppm Farmer 2004 Zhang & O'Reilly 1997 Basic Precambrian Granulites 73 Ta 1.6         25 ppm Shaw et al. 1986 Boninites 73 Ta 0.13         22 ppm Kelemen et al. 2004 Brown Clay 73 Ta 0.628         29 ppm Plank & Langmuir 1998 Brown Clay 73 Ta 0.527         4 ppm Plank & Langmuir 1998 Carbonate 73 Ta 0.056         13 ppm Plank & Langmuir 1998 Carbonate Turbidites 73 Ta 0.41         87 ppm Plank & Langmuir 1998 Carbonates 73 Ta 0.14         50 ppm Gao et al. 1998 Carbonates 73 Ta 0.4         2038 ppm Gao et al. 1998 Cascade Basalt 73 Ta 0.48         17 ppm Kelemen et al. 2004 Cascadia Trench 73 Ta 0.704           ppm Plank & Langmuir 1998 Central America Trench 73 Ta 0.127           ppm Plank & Langmuir 1998 Central American Basalts 73 Ta 0.29         17 ppm Kelemen et al. 2004 Central East China Craton 73 Ta 0.68           ppm Gao et al. 1998 Central East China Craton 73 Ta 0.63           ppm Gao et al. 1998 Central East China Craton 73 Ta 0.58           ppm Gao et al. 1998 Central East China Craton 73 Ta 0.62           ppm Gao et al. 1998 Central East China Craton 73 Ta 0.6           ppm Gao et al. 1998 Central East China Craton 73 Ta 0.53           ppm Gao et al. 1998 Central East China Craton 73 Ta 0.55           ppm Gao et al. 1998 Central East China Craton 73 Ta 0.55           ppm Gao et al. 1998 Central East China Craton 73 Ta 0.52           ppm Gao et al. 1998 Central East China Craton 73 Ta 0.74           ppm Gao et al. 1998 Central East China Craton 73 Ta 0.63           ppm Gao et al. 1998 Chert 73 Ta 0.406         4 ppm Plank & Langmuir 1998 Chert 73 Ta 0.182         4 ppm Plank & Langmuir 1998 Chert 73 Ta 0.41           ppm Elliot et al. 1997 CI Chondrites 73 Ta 0.0142           ppm Palme & Jones 2004 Anders & Grevesse 1989 CI Chondrites 73 Ta 0.0142   0.000852       ppm Palme & Jones 2004 Palme & Beer 1993 Jochum et al. 2000 CI Chondrites 73 Ta 0.02           ppm McDonough et al. 1992 Clastic Turbidites 73 Ta 0.704         28 ppm Plank & Langmuir 1998 Colombia Trench 73 Ta 0.146           ppm Plank & Langmuir 1998 Continental Arc Andesite 73 Ta 0.45         83 ppm Kelemen et al. 2004 Continental Arc Andesite 73 Ta 0.85         22 ppm Kelemen et al. 2004 Continental Arcs 73 Ta 0.6           ppm Rudnick & Fountain 1995 Continental Arcs 73 Ta 1.1           ppm Rudnick & Fountain 1995 Continental Crust 73 Ta 1.1           ppm Wedepohl 1995 Continental Crust 73 Ta 4           ppm Shaw et al. 1986 Continental Crust 73 Ta 1.1           ppm Rudnick & Fountain 1995 Wedepohl 1995 Continental Crust 73 Ta 0.7           ppm Plank & Langmuir 1998 Continental Crust 73 Ta 1           ppm Taylor & McLennan 1995 Continental Crust 73 Ta 1.1           ppm Rudnick & Fountain 1995 Continental Crust 73 Ta 0.7           ppm Kemp & Hawkesworth 2004 Rudnick & Gao 2004 Continental Intraplate Xenoliths 73 Ta 0.002           ppm Pearson et al. 2004 Ionov 1996 Continental Intraplate Xenoliths 73 Ta 0.001           ppm Pearson et al. 2004 Bedini & Bodinier 1999 Continental Intraplate Xenoliths 73 Ta 0.041           ppm Pearson et al. 2004 Eggins et al. 1998 Continental Intraplate Xenoliths 73 Ta 0.001           ppm Pearson et al. 2004 Eggins et al. 1998 Continental Intraplate Xenoliths 73 Ta 2.79           ppm Pearson et al. 2004 Gregoire et al. 2002 Continental Intraplate Xenoliths 73 Ta 6.65           ppm Pearson et al. 2004 Ionov et al. 1997 Continental Intraplate Xenoliths 73 Ta 0.002           ppm Pearson et al. 2004 Bedini & Bodinier 1999 Continental Intraplate Xenoliths 73 Ta 0.002           ppm Pearson et al. 2004 Bedini & Bodinier 1999 Continental Intraplate Xenoliths 73 Ta 0.04           ppm Pearson et al. 2004 Ionov 1996 Continental Intraplate Xenoliths 73 Ta 1.33           ppm Pearson et al. 2004 Glaser et al. 1999 Continental Intraplate Xenoliths 73 Ta 0.007           ppm Pearson et al. 2004 Ionov 1996 Continental Intraplate Xenoliths 73 Ta 0.007           ppm Pearson et al. 2004 Eggins et al. 1998 Continental Intraplate Xenoliths 73 Ta 0.0033           ppm Pearson et al. 2004 Ionov 1996 Continental Intraplate Xenoliths 73 Ta 0.215           ppm Pearson et al. 2004 Eggins et al. 1998 Continental Intraplate Xenoliths 73 Ta 0.37           ppm Pearson et al. 2004 Ionov et al. 1997 Continental Intraplate Xenoliths 73 Ta 0.083           ppm Pearson et al. 2004 Johnson et al. 1996 Continental Intraplate Xenoliths 73 Ta 0.0001           ppm Pearson et al. 2004 Bedini & Bodinier 1999 Continental Intraplate Xenoliths 73 Ta 0.058           ppm Pearson et al. 2004 Eggins et al. 1998 Continental Intraplate Xenoliths 73 Ta 0.12           ppm Pearson et al. 2004 Bedini & Bodinier 1999 Continental Shields & Platforms 73 Ta 1.1           ppm Rudnick & Fountain 1995 Continental Shields & Platforms 73 Ta 0.6           ppm Rudnick & Fountain 1995 Cratonic Xenoliths 73 Ta 90           ppm Pearson et al. 2004 Gregoire et al. 2002 Cratonic Xenoliths 73 Ta 46           ppm Pearson et al. 2004 Gregoire et al. 2002 Cratonic Xenoliths 73 Ta 0.06           ppm Pearson et al. 2004 Gregoire et al. 2002 Cratonic Xenoliths 73 Ta 0.01           ppm Pearson et al. 2004 Gergoire et al. 2002 Cratonic Xenoliths 73 Ta 0.06           ppm Pearson et al. 2004 Gregoire et al. 2002 Cratonic Xenoliths 73 Ta 0.039           ppm Pearson et al. 2004 Cratonic Xenoliths 73 Ta 0.071           ppm Pearson et al. 2004 Cratonic Xenoliths 73 Ta 40           ppm Pearson et al. 2004 Gregoire et al. 2002 Depleted Mantle 73 Ta 0.0096     0.0082 0.0108   ppm Workman & Hart 2005 Depleted-Depleted MORB Mantle 73 Ta 0.0056           ppm Workman & Hart 2005 Diatom Oozes & Clay 73 Ta 0.321         15 ppm Plank & Langmuir 1998 Diatome Clay 73 Ta 0.42         6 ppm Plank & Langmuir 1998 Diatome Mud 73 Ta 0.354         6 ppm Plank & Langmuir 1998 Diatome Ooze 73 Ta 0.391         4 ppm Plank & Langmuir 1998 Diorite 73 Ta 1.46         260 ppm Gao et al. 1998 DSDP/ODP Site 800 73 Ta 0.647           ppm Plank & Langmuir 1998 DSDP/ODP Site 801 73 Ta 0.869           ppm Plank & Langmuir 1998 DSDP/ODP Site 801 73 Ta 0.87           ppm Elliot et al. 1997 E-MORB 73 Ta 0.77           ppm Klein 2004 Lehnert 2000 Early Archean Upper Crust 73 Ta 0.7           ppm Condie 1993 Early Archean Upper Crust 73 Ta 0.69           ppm Condie 1993 Early Proterozoic Upper Crust 73 Ta 0.88           ppm Condie 1993 Early Proterozoic Upper Crust 73 Ta 0.95           ppm Condie 1993 East China Craton 73 Ta 0.61           ppm Gao et al. 1998 East China Craton 73 Ta 0.63           ppm Gao et al. 1998 East Sunda Trench 73 Ta 0.693           ppm Plank & Langmuir 1998 Enriched-Depleted MORB Mantle 73 Ta 0.0159           ppm Workman & Hart 2005 Felsic Archean Granulites 73 Ta 0.58 0.35       34 ppm Rudnick & Fountain 1995 Felsic Granulites 73 Ta 0.4         137 ppm Gao et al. 1998 Felsic Post-Archean Granulites 73 Ta 0.8 0.5       1 ppm Rudnick & Fountain 1995 Felsic Volcanics 73 Ta 1           ppm Condie 1993 Felsic Volcanics 73 Ta 0.88         972 ppm Gao et al. 1998 Felsic Volcanics 73 Ta 0.8           ppm Condie 1993 Felsic Volcanics 73 Ta 1.3           ppm Condie 1993 Felsic Volcanics 73 Ta 1.2           ppm Condie 1993 Felsic Volcanics 73 Ta 1.7           ppm Condie 1993 Felsic Volcanics 73 Ta 1.4           ppm Condie 1993 Felsic Volcanics 73 Ta 1.6           ppm Condie 1993 Fresh Mid-Ocean Ridge Basalts 73 Ta 0.31         28 ppm Kelemen et al. 2004 Granites 73 Ta 1.8         1226 ppm Gao et al. 1998 Granites 73 Ta 0.45         8 ppm Kemp & Hawkesworth 2004 Kemp 2001 Granites 73 Ta 0.7         402 ppm Gao et al. 1998 Granites 73 Ta 0.93           ppm Kemp & Hawkesworth 2004 Sylvester 1995 Granites 73 Ta 1.7           ppm Condie 1993 Granites 73 Ta 1           ppm Condie 1993 Granites 73 Ta 1.5           ppm Condie 1993 Granulites 73 Ta 1.55         16 ppm Rudnick & Presper 1990 Granulites 73 Ta 0.52 0.25       50 ppm Rudnick & Presper 1990 Granulitic Xenolites 73 Ta 0.6         14 ppm Rudnick & Presper 1990 Graywackes 73 Ta 0.8           ppm Condie 1993 Graywackes 73 Ta 0.7           ppm Condie 1993 Graywackes 73 Ta 0.8           ppm Condie 1993 Graywackes 73 Ta 0.9           ppm Condie 1993 Graywackes 73 Ta 0.76           ppm Condie 1993 Graywackes 73 Ta 0.85           ppm Condie 1993 Green Clay 73 Ta 0.634         3 ppm Plank & Langmuir 1998 Hydrothermal Sediment 73 Ta 0.155         4 ppm Plank & Langmuir 1998 Interior North China Craton 73 Ta 0.42           ppm Gao et al. 1998 Interior North China Craton 73 Ta 0.61           ppm Gao et al. 1998 Interior North China Craton 73 Ta 0.68           ppm Gao et al. 1998 Interior North China Craton 73 Ta 0.56           ppm Gao et al. 1998 Interior North China Craton 73 Ta 0.49           ppm Gao et al. 1998 Interlayerd Clay & Chert 73 Ta 0.07         2 ppm Plank & Langmuir 1998 Interlayered Chert & Limestone 73 Ta 0.187         5 ppm Plank & Langmuir 1998 Interlayered Clay & Chert 73 Ta 0.483         12 ppm Plank & Langmuir 1998 Intermediate Granulites 73 Ta 0.4         136 ppm Gao et al. 1998 Intermediate Mafic Archean Granulites 73 Ta 0.62 0.63       5 ppm Rudnick & Fountain 1995 Intermediate Mafic Granulitic Xenolites 73 Ta 0.6         1 ppm Rudnick & Fountain 1995 Intermediate Mafic Post-Archean Granulites 73 Ta 1.4 1.4       4 ppm Rudnick & Fountain 1995 Intermediate Precambrian Granulites 73 Ta 1.6         26 ppm Shaw et al. 1986 Island Arc Andesite 73 Ta 0.08         4 ppm Kelemen et al. 2004 Island Arc Andesite 73 Ta 0.24         64 ppm Kelemen et al. 2004 Izu-Bonin Trench 73 Ta 0.239           ppm Plank & Langmuir 1998 Japan Trench 73 Ta 0.319           ppm Plank & Langmuir 1998 Java Trench 73 Ta 0.848           ppm Plank & Langmuir 1998 Kamchatka Basalt 73 Ta 0.13         22 ppm Kelemen et al. 2004 Kamchatka Trench 73 Ta 0.133           ppm Plank & Langmuir 1998 Kerm Trench 73 Ta 651           ppm Plank & Langmuir 1998 Kermadec Basalts 73 Ta 0.26         10 ppm Kelemen et al. 2004 Kimberlite 73 Ta 15.72         22 ppm Farmer 2004 Taylor et al. 1994 Komatiites 73 Ta 0.05           ppm Condie 1993 Kuriles Trench 73 Ta 0.319           ppm Plank & Langmuir 1998 Late Archean Upper Crust 73 Ta 0.69           ppm Condie 1993 Late Archean Upper Crust 73 Ta 0.69           ppm Condie 1993 Late Proterozoic Upper Crust 73 Ta 0.97           ppm Condie 1993 Late Proterozoic Upper Crust 73 Ta 0.9           ppm Condie 1993 Lesser Antilles Basalt 73 Ta 0.26         11 ppm Kelemen et al. 2004 Lower Continental Crust 73 Ta 0.84           ppm Wedepohl 1995 Lower Continental Crust 73 Ta 0.6           ppm Taylor & McLennan 1995 Lower Continental Crust 73 Ta 0.6           ppm Kemp & Hawkesworth 2004 Rudnick & Gao 2004 Lower Continental Crust 73 Ta 2           ppm Shaw et al. 1986 Lower Continental Crust 73 Ta 0.6           ppm Rudnick & Fountain 1995 Luzon Basalt 73 Ta 0.16         5 ppm Kelemen et al. 2004 Mafic Archean Granulites 73 Ta 0.3 0.2       8 ppm Rudnick & Fountain 1995 Mafic Granulites 73 Ta 0.65         128 ppm Gao et al. 1998 Mafic Granulitic Xenolites 73 Ta 0.55 0.5       18 ppm Rudnick & Fountain 1995 Mafic Intrusions 73 Ta 0.72         308 ppm Gao et al. 1998 Mafic Post-Archean Granulites 73 Ta 0.6 0.2       12 ppm Rudnick & Fountain 1995 Makran Trench 73 Ta 0.925           ppm Plank & Langmuir 1998 Manganese Nodules 73 Ta 10           ppm Li 1991 Baturin 1988 Marianas Basalt 73 Ta 0.14         12 ppm Kelemen et al. 2004 Marianas Trench 73 Ta 0.758           ppm Plank & Langmuir 1998 Marine Pelagic Clay 73 Ta 1           ppm Li 1991 Turekian & Wedepohl 1961 Marine Pelagic Clay 73 Ta 1           ppm Li 1982 Turekian & Wedepohl 1961 Brewer 1975 Marine Shales 73 Ta 0.8           ppm Li 1991 Turekian & Wedepohl 1961 Mavic Volcanics 73 Ta 1.04         632 ppm Gao et al. 1998 Mesozoic & Cenozoic Extensions 73 Ta 1.2           ppm Rudnick & Fountain 1995 Mesozoic & Cenozoic Extensions 73 Ta 0.8           ppm Rudnick & Fountain 1995 Mesozoic & Cenozoic Orogens 73 Ta 1.2           ppm Rudnick & Fountain 1995 Mesozoic & Cenozoic Orogens 73 Ta 0.8           ppm Rudnick & Fountain 1995 Mesozoic & Cenozoic Upper Crust 73 Ta 0.9           ppm Condie 1993 Mesozoic & Cenozoic Upper Crust 73 Ta 0.96           ppm Condie 1993 Metafelsic Volcanics 73 Ta 0.56         41 ppm Gao et al. 1998 Metalliferous Clay 73 Ta 0.867         12 ppm Plank & Langmuir 1998 Metapelitic Granulitic Xenolites 73 Ta 1.3 1       15 ppm Rudnick & Fountain 1995 Mexico Trench 73 Ta 0.675           ppm Plank & Langmuir 1998 Middle Continental Crust 73 Ta 0.6           ppm Rudnick & Fountain 1995 Middle Continental Crust 73 Ta 0.6           ppm Kemp & Hawkesworth 2004 Rudnick & Gao 2004 Middle Proterozoic Upper Crust 73 Ta 0.86           ppm Condie 1993 Middle Proterozoic Upper Crust 73 Ta 0.94           ppm Condie 1993 N-MORB 73 Ta 0.309           ppm Klein 2004 Thompson et al. 1980 N-MORB 73 Ta 0.203           ppm Klein 2004 Niu et al. 1999 N-MORB 73 Ta 0.192   0.106     26 ppm Hofmann 1988 Jochum et al. 1988 N-MORB 73 Ta 0.13           ppm Klein 2004 Lehnert 2000 Nankai Trench 73 Ta 1.008           ppm Plank & Langmuir 1998 Nanno Ooze 73 Ta 0.05         2 ppm Plank & Langmuir 1998 Nano Ooze 73 Ta 0.135         4 ppm Plank & Langmuir 1998 New Hebrides Islands 73 Ta 0.16         6 ppm Kelemen et al. 2004 North American Shale Composite (NASC) 73 Ta 1.1           ppm Condie 1993 North Antilles Trench 73 Ta 1.118           ppm Plank & Langmuir 1998 North Qinling Belt in China 73 Ta 1           ppm Gao et al. 1998 North Qinling Belt in China 73 Ta 1.15           ppm Gao et al. 1998 North Qinling Belt in China 73 Ta 1.31           ppm Gao et al. 1998 North Qinling Belt in China 73 Ta 1.2           ppm Gao et al. 1998 North Qinling Belt in China 73 Ta 0.66           ppm Gao et al. 1998 Oceanic Plateaus 73 Ta 0.2           ppm Kerr 2004 Mahoney et al. 1993 Oceanic Plateaus 73 Ta 0.35           ppm Kerr 2004 Tejada et al. 2002 Oceanic Plateaus 73 Ta 9.08           ppm Kerr 2004 Salters et al. 1992 Oceanic Plateaus 73 Ta 0.25           ppm Kerr 2004 Tejada et al. 2002 Oceanic Plateaus 73 Ta 7.3           ppm Kerr 2004 Tejada et al. 2002 Oceanic Plateaus 73 Ta 7.45           ppm Kerr 2004 Tejada et al. 2002 Oceanic Plateaus 73 Ta 7.22           ppm Kerr 2004 Salters et al. 1992 Oceanic Plateaus 73 Ta 8.58           ppm Kerr 2004 Hauff et al. 2000 Oceanic Plateaus 73 Ta 18.25           ppm Kerr 2004 Aitken & Echeverria 1984 Dupre & Echeverria 1984 Jochum et al. 1991 Oceanic Plateaus 73 Ta 0.4           ppm Kerr 2004 Salters et al. 1992 Oceanic Plateaus 73 Ta 8.65           ppm Kerr 2004 Aitken & Echeverria 1984 Dupre & Echeverria 1984 Jochum et al. 1991 Oceanic Plateaus 73 Ta 8.36           ppm Kerr 2004 Salters et al. 1992 Oceanic Plateaus 73 Ta 8.96           ppm Kerr 2004 Reynaud et al. 1999 Oceanic Plateaus 73 Ta 0.23           ppm Kerr 2004 Hauff et al. 2000 Oceanic Plateaus 73 Ta 0.19           ppm Kerr 2004 Salters et al. 1992 Oceanic Plateaus 73 Ta 5.51           ppm Kerr 2004 Mahoney et al. 1995 Oceanic Plateaus 73 Ta 0.58           ppm Kerr 2004 Reynaud et al. 1999 Oceanic Plateaus 73 Ta 0.54           ppm Kerr 2004 Mahoney et al. 1995 Oceanic Plateaus 73 Ta 6.74           ppm Kerr 2004 Mahoney et al. 1993 Oceanic Plateaus 73 Ta 21.96           ppm Kerr 2004 Oceanic Plateaus 73 Ta 6.77           ppm Kerr 2004 Kerr et al. 1997 Hauff et al. 2000 Oceanic Plateaus 73 Ta 8.03           ppm Kerr 2004 Tejada et al. 1996 Oceanic Plateaus 73 Ta 5.78           ppm Kerr 2004 Kerr et al. 1997 Hauff et al. 2000 Oceanic Plateaus 73 Ta 11.55           ppm Kerr 2004 Kerr et al. 2002 Oceanic Plateaus 73 Ta 22.86           ppm Kerr 2004 Kerr et al. 1996 Oceanic Plateaus 73 Ta 0.46           ppm Kerr 2004 Salters et al. 1992 Oceanic Plateaus 73 Ta 7.54           ppm Kerr 2004 Salters et al. 1992 Oceanic Plateaus 73 Ta 0.34           ppm Kerr 2004 Mahoney et al. 1993 Oceanic Plateaus 73 Ta 8.6           ppm Kerr 2004 Kerr et al. 1996 Oceanic Plateaus 73 Ta 0.3           ppm Kerr 2004 Kerr et al. 1997 Hauff et al. 2000 Oceanic Plateaus 73 Ta 0.48           ppm Kerr 2004 Kerr et al. 1997 Hauff et al. 2000 Oceanic Plateaus 73 Ta 7.47           ppm Kerr 2004 Salters et al. 1992 Oceanic Plateaus 73 Ta 7.43           ppm Kerr 2004 Mahoney et al. 1993 ODP/DSDP Site 417/418 73 Ta 0.097           ppm Staudigel et al. 1996 Orangeite 73 Ta 8.5         114 ppm Farmer 2004 Mitchell 1995 Paleozoic Orogens 73 Ta 0.9           ppm Rudnick & Fountain 1995 Paleozoic Orogens 73 Ta 0.7           ppm Rudnick & Fountain 1995 Paleozoic Upper Crust 73 Ta 0.9           ppm Condie 1993 Paleozoic Upper Crust 73 Ta 0.97           ppm Condie 1993 Pelagic Clay 73 Ta 0.81           ppm Elliot et al. 1997 Pelagic Clay 73 Ta 0.739         56 ppm Plank & Langmuir 1998 Pelagic Clay 73 Ta 1.056         8 ppm Plank & Langmuir 1998 Pelagic Clay 73 Ta 0.833         6 ppm Plank & Langmuir 1998 Pelagic Clay 73 Ta 0.81         6 ppm Plank & Langmuir 1998 Pelagic Clay 73 Ta 0.739         56 ppm Plank & Langmuir 1998 Pelagic Clay 73 Ta 1.008         55 ppm Plank & Langmuir 1998 Pelagic Clay 73 Ta 0.053         3 ppm Plank & Langmuir 1998 Pelites 73 Ta 1.18         1341 ppm Gao et al. 1998 Pelites 73 Ta 0.95         69 ppm Gao et al. 1998 Peninsular Range Batholith 73 Ta 0.29           ppm Kemp & Hawkesworth 2004 Sylvester 1995 Peru Trench 73 Ta 0.261           ppm Plank & Langmuir 1998 Phanerozoic Flood Basalts 73 Ta 0.8         6 ppm Farmer 2004 Lightfoot et al. 1990 Phanerozoic Flood Basalts 73 Ta 0.92         36 ppm Farmer 2004 Hooper & Hawkesworth 1993 Phanerozoic Flood Basalts 73 Ta 1.3         18 ppm Farmer 2004 Lightfoot et al. 1990 Phanerozoic Flood Basalts 73 Ta 0.48         9 ppm Farmer 2004 Wooden et al. 1993 Phanerozoic Flood Basalts 73 Ta 1.92         1 ppm Farmer 2004 Peate 1997 Phanerozoic Flood Basalts 73 Ta 0.5         1 ppm Farmer 2004 Peate 1997 Phanerozoic Flood Basalts 73 Ta 0.37         1 ppm Farmer 2004 Peate 1997 Phanerozoic Flood Basalts 73 Ta 0.47         7 ppm Farmer 2004 Wooden et al. 1993 Philip Trench 73 Ta 0.287           ppm Plank & Langmuir 1998 Precambrian Canadian Shield 73 Ta 5.7           ppm Shaw et al. 1986 Precambrian Granulites 73 Ta 2.3         88 ppm Shaw et al. 1986 Primitive Mantle 73 Ta 0.035           ppm Wedepohl & Hartmann 1994 Hofmann 1988 Primitive Mantle 73 Ta 0.03           ppm Wedepohl & Hartmann 1994 Jagoutz et al. 1979 Primitive Mantle 73 Ta 0.0351           ppm Hofmann 1988 Hart & Zindler 1986 Protolith Gabbros at ODP Site 735 73 Ta 0.04         8 ppm Hart et al. 1999 Radiolarian Clay 73 Ta 0.89         8 ppm Plank & Langmuir 1998 Radiolarian Clay 73 Ta 0.89         8 ppm Plank & Langmuir 1998 Radiolarian Clay 73 Ta 0.65         2 ppm Plank & Langmuir 1998 Radiolarites 73 Ta 0.33         17 ppm Plank & Langmuir 1998 Radiolarites 73 Ta 0.285         4 ppm Plank & Langmuir 1998 Radiolarites 73 Ta 0.29           ppm Elliot et al. 1997 Rifted Continental Margins 73 Ta 1.1           ppm Rudnick & Fountain 1995 Rifted Continental Margins 73 Ta 0.6           ppm Rudnick & Fountain 1995 Ryuku Trench 73 Ta 0.831           ppm Plank & Langmuir 1998 Sandstones 73 Ta 0.31           ppm Condie 1993 Sandstones 73 Ta 0.24           ppm Condie 1993 Sandstones 73 Ta 0.3           ppm Condie 1993 Scotia Island Basalt 73 Ta 0.5         11 ppm Kelemen et al. 2004 Shales 73 Ta 1.4           ppm Condie 1993 Shales 73 Ta 1.4           ppm Condie 1993 Shales 73 Ta 0.84           ppm Condie 1993 Silicate Earth 73 Ta 0.04           ppm McDonough et al. 1992 Taylor & McLennan 1985 Silicate Earth 73 Ta 0.0351           ppm McDonough et al. 1992 Hofmann 1988 Silicate Earth 73 Ta 0.038           ppm McDonough et al. 1992 Jagoutz et al. 1979 Wanke et al. 1984 Silicate Earth 73 Ta 0.041           ppm McDonough et al. 1992 Sun 1982 Sun & McDonough 1989 McDonough & Frey 1989 Silicate Earth 73 Ta 0.037           ppm McDonough 2004 Silicic Precambrian Granulites 73 Ta 2.9         23 ppm Shaw et al. 1986 Silicified Limestone 73 Ta 0.17           ppm Plank & Langmuir 1998 Silty Mud 73 Ta 0.703         16 ppm Plank & Langmuir 1998 Solid Earth 73 Ta 0.025           ppm McDonough 2004 South Antilles Trench 73 Ta 1.3           ppm Plank & Langmuir 1998 South Margin of North China Craton 73 Ta 0.57           ppm Gao et al. 1998 South Margin of North China Craton 73 Ta 0.63           ppm Gao et al. 1998 South Margin of North China Craton 73 Ta 0.51           ppm Gao et al. 1998 South Margin of North China Craton 73 Ta 0.73           ppm Gao et al. 1998 South Margin of North China Craton 73 Ta 0.78           ppm Gao et al. 1998 South Qinling Belt in China 73 Ta 0.72           ppm Gao et al. 1998 South Qinling Belt in China 73 Ta 0.84           ppm Gao et al. 1998 South Qinling Belt in China 73 Ta 0.78           ppm Gao et al. 1998 South Qinling Belt in China 73 Ta 0.66           ppm Gao et al. 1998 South Sandwich Trench 73 Ta 0.321           ppm Plank & Langmuir 1998 Spinel Peridotites 73 Ta 0.4 0.23 0.51     38 ppm McDonough 1990 Subducted Sediment 73 Ta 0.63   0.06       ppm Plank & Langmuir 1998 Sumatra Trench 73 Ta 0.803           ppm Plank & Langmuir 1998 Talkeetna Arc Plutonic Rocks 73 Ta 0.028   0.001     31 ppm Kelemen et al. 2004 Talkeetna Arc Plutonic Rocks 73 Ta 0.05   0.012     6 ppm Kelemen et al. 2004 Talkeetna Arc Plutonic Rocks 73 Ta 0.174   0.009     13 ppm Kelemen et al. 2004 Talkeetna Arc Plutonic Rocks 73 Ta 0.147   0.003     42 ppm Kelemen et al. 2004 Talkeetna Arc Plutonic Rocks 73 Ta 0.116   0.036     7 ppm Kelemen et al. 2004 Talkeetna Arc Plutonic Rocks 73 Ta 0.012   0.001     16 ppm Kelemen et al. 2004 Tonalites 73 Ta 1.1           ppm Wedepohl 1995 Tonalites-Trondhjemites-Granodiorites 73 Ta 0.71         355 ppm Kemp & Hawkesworth 2004 Martin 1995 Tonalites-Trondhjemites-Granodiorites 73 Ta 0.8           ppm Condie 1993 Tonalites-Trondhjemites-Granodiorites 73 Ta 0.65           ppm Condie 1993 Tonalites-Trondhjemites-Granodiorites 73 Ta 0.39         553 ppm Gao et al. 1998 Tonalites-Trondhjemites-Granodiorites 73 Ta 0.93         641 ppm Gao et al. 1998 Tonalites-Trondhjemites-Granodiorites 73 Ta 0.7           ppm Condie 1993 Tonga Trench 73 Ta 0.552           ppm Plank & Langmuir 1998 Tongan Basalts 73 Ta 0.04         5 ppm Kelemen et al. 2004 Transitional Mid-Ocean Ridge Basalts 73 Ta 0.38           ppm Klein 2004 Lehnert 2000 Turbidites 73 Ta 0.5         4 ppm Plank & Langmuir 1998 Turbidites 73 Ta 0.797         4 ppm Plank & Langmuir 1998 Ultrabasic Precambrian Granulites 73 Ta 2.4         14 ppm Shaw et al. 1986 Upper Continental Crust 73 Ta 0.9           ppm Kemp & Hawkesworth 2004 Rudnick & Gao 2004 Upper Continental Crust 73 Ta 0.96   0.12       ppm Plank & Langmuir 1998 Upper Continental Crust 73 Ta 0.79           ppm Condie 1993 Upper Continental Crust 73 Ta 0.82           ppm Condie 1993 Upper Continental Crust 73 Ta 2.2           ppm Taylor & McLennan 1995 Upper Continental Crust 73 Ta 1.5           ppm Wedepohl 1995 Vanuatu Trench 73 Ta 0.136           ppm Plank & Langmuir 1998 Volcanoclastic Sediment 73 Ta 0.119         15 ppm Plank & Langmuir 1998 Volcanoclastic Turbidites 73 Ta 1.663         13 ppm Plank & Langmuir 1998 Volcanoclastic Turbidites 73 Ta 1.226         43 ppm Plank & Langmuir 1998 Volcanoclastic Turbidites 73 Ta 1.66           ppm Elliot et al. 1997 Yangtze Craton 73 Ta 0.68           ppm Gao et al. 1998 Yangtze Craton 73 Ta 0.64           ppm Gao et al. 1998 Yangtze Craton 73 Ta 0.59           ppm Gao et al. 1998 Yangtze Craton 73 Ta 0.73           ppm Gao et al. 1998 Yangtze Craton 73 Ta 0.57           ppm Gao et al. 1998 Solar System 73 Ta 0.02             Anders & Ebihara 1982 Cameron 1982 Solar System 73 Ta 0.0226   0.00226     1   Anders & Ebihara 1982 Solar System 73 Ta 0.0207   0.000373     2   Anders & Grevesse 1989 CI Chondrites 73 Ta -0.14   0.06         Palme & Jones 2004 ALH 77005 Meteorite 73 Ta 33   7       ppb McSween, Jr. 2004 Lodders 1998 ALH 84001 Meteorite 73 Ta 32           ppb McSween, Jr. 2004 Lodders 1998 Chassigny Meteorite 73 Ta 20           ppb McSween, Jr. 2004 Lodders 1998 CI Chondrites 73 Ta 14.2   0.26     2 ppb Anders & Grevesse 1989 CI Chondrites 73 Ta 14.2   0.852       ppb Palme & O'Neill 2004 Palme & Jones 2004 CI Chondrites 73 Ta 14           ppb McDonough & Sun 1995 Palme 1988 CI Chondrites 73 Ta 16           ppb McDonough & Sun 1995 Wasson & Kallemeyn 1988 CI Chondrites 73 Ta 13.6           ppb McDonough & Sun 1995 Continental Crust 73 Ta 1000           ppb Palme & O'Neill 2004 Rudnick & Gao 2004 Depleted Mantle 73 Ta 13.8   4.554       ppb Salters & Stracke 2004 Nakhla Meteorite 73 Ta 90           ppb McSween, Jr. 2004 Lodders 1998 Orgueil Chondrite 73 Ta 17         1 ppb Anders & Ebihara 1982 Orgueil Chondrite 73 Ta 14         1 ppb Anders & Grevesse 1989 Primitive Mantle 73 Ta 40   4       ppb Palme & O'Neill 2004 Primitive Mantle 73 Ta 40           ppb Palme & O'Neill 2004 Primitive Mantle 73 Ta 37   5.6       ppb McDonough & Sun 1995 QUE 94201 Meteorite 73 Ta 23           ppb McSween, Jr. 2004 Lodders 1998 Seawater 73 Ta 0.002           ppb Li 1982 Shergotty Meteorite 73 Ta 250   40       ppb McSween, Jr. 2004 Lodders 1998 Silicate Earth 73 Ta 37   5.6       ppb McDonough & Sun 1995 ALHA77081 Acapulcoite 73 Ta 50           ng/g Mittlefehldt 2004 Schultz et al. 1982 Angrite Angra Dos Reis 73 Ta 350           ng/g Mittlefehldt 2004 Mittlefehldt & Lindstrom 1990 Angrite LEW 87051 73 Ta 110           ng/g Mittlefehldt 2004 Mittlefehldt & Lindstrom 1990 Barea Mesosiderite 73 Ta 54           ng/g Mittlefehldt 2004 Mason & Jarosewich 1973 Mittlefehldt in press Binda Eucrite 73 Ta 21           ng/g Mittlefehldt 2004 Barrat et al. 2000 McCarthy et al. 1973 Chaunskij Mesosiderite 73 Ta 52           ng/g Mittlefehldt 2004 Mittlefehldt in press Petaev et al. 2000 D'Orbigny Angrite 73 Ta 200           ng/g Mittlefehldt 2004 Mittlefehldt et al. 2002 EET 84302 Acapulcoite 73 Ta 10           ng/g Mittlefehldt 2004 Weigel et al. 1999 Estherville Mesosiderite 73 Ta 69           ng/g Mittlefehldt 2004 Mittlefehldt in press Simpson & Ahrens 1977 Frankfort Howardites 73 Ta 40           ng/g Mittlefehldt 2004 McCarthy et al. 1972 Palme et al. 1978 Gibson Lodranite 73 Ta 14           ng/g Mittlefehldt 2004 Weigel et al. 1999 Ibitira Eucrite 73 Ta 153           ng/g Mittlefehldt 2004 Jarosewich 1990 Barrat et al. 2000 Kapoeta Howardites 73 Ta 100           ng/g Mittlefehldt 2004 Wanke et al. 1972 MAC 88177 Lodranite 73 Ta 14           ng/g Mittlefehldt 2004 Weigel et al. 1999 Macibini Eucrites 73 Ta 180           ng/g Mittlefehldt 2004 McCarthy et al. 1973 Buchanan et al. 2000b Malvern Howardites 73 Ta 110           ng/g Mittlefehldt 2004 Palme et al. 1978 Moore County Eucrite 73 Ta 30           ng/g Mittlefehldt 2004 Barrat et al. 2000 McCarthy et al. 1973 Nuevo Laredo Eucrite 73 Ta 178           ng/g Mittlefehldt 2004 Warren & Jerde 1987 Petersburg Eucrites 73 Ta 144           ng/g Mittlefehldt 2004 Mason et al. 1979 Buchanan & Reid 1996 Serra De Mage Eucrite 73 Ta 31           ng/g Mittlefehldt 2004 Barrat et al. 2000 McCarthy et al. 1973 Sioux County Eucrite 73 Ta 147           ng/g Mittlefehldt 2004 Barrat et al. 2000 McCarthy et al. 1973 Stannern Eucrite 73 Ta 368           ng/g Mittlefehldt 2004 Barrat et al. 2000 McCarthy et al. 1973 Watson IIE Iron 73 Ta 8.9           ng/g Mittlefehldt 2004 Olsen et al. 1994 Y-74450 Eucrites 73 Ta 300           ng/g Mittlefehldt 2004 Wanke et al. 1977 Y-791491 Lodranite 73 Ta 11           ng/g Mittlefehldt 2004 Weigel et al. 1999 Seawater 73 Ta         14     Bruland 1983 Amazon River Particulates 73 Ta 2           µg/g Martin & Meybeck 1979 Congo River Particulates 73 Ta 1.1           µg/g Martin & Meybeck 1979 Continental Crust 73 Ta 4           µg/g Rudnick & Gao 2004 Shaw et al. 1986 Continental Crust 73 Ta 0.7           µg/g Rudnick & Gao 2004 Rudnick & Fountain 1995 Continental Crust 73 Ta 0.7           µg/g Rudnick & Gao 2004 Rudnick & Fountain 1995 Continental Crust 73 Ta 0.7           µg/g Rudnick & Gao 2004 Continental Crust 73 Ta 0.8           µg/g Rudnick & Gao 2004 Taylor & McLennan 1985 Taylor & McLennan 1995 Continental Crust 73 Ta 2           µg/g Rudnick & Gao 2004 Taylor 1964 Continental Crust 73 Ta 0.6           µg/g Rudnick & Gao 2004 Gao et al. 1998a Continental Crust 73 Ta 1.1           µg/g Rudnick & Gao 2004 Wedepohl 1995 Core 73 Ta 0           µg/g McDonough 1998 Ganges River Particulates 73 Ta 1.25           µg/g Martin & Meybeck 1979 Lower Continental Crust 73 Ta 1.3           µg/g Rudnick & Gao 2004 Shaw et al. 1994 Lower Continental Crust 73 Ta 0.6           µg/g Rudnick & Gao 2004 Rudnick & Fountain 1995 Lower Continental Crust 73 Ta 0.5           µg/g Rudnick & Gao 2004 Rudnick & Presper 1990 Lower Continental Crust 73 Ta 0.7           µg/g Rudnick & Gao 2004 Taylor & McLennan 1985 Taylor & McLennan 1995 Lower Continental Crust 73 Ta 0.6           µg/g Rudnick & Gao 2004 Gao et al. 1998a Lower Continental Crust 73 Ta 0.6           µg/g Rudnick & Gao 2004 Rudnick & Fountain 1995 Lower Continental Crust 73 Ta 0.8           µg/g Rudnick & Gao 2004 Wedepohl 1995 Lower Continental Crust 73 Ta 0.3           µg/g Rudnick & Gao 2004 Liu et al. 2001 Lower Continental Crust 73 Ta 2.1           µg/g Rudnick & Gao 2004 Villaseca et al. 1999 Lower Continental Crust 73 Ta 0.5           µg/g Rudnick & Gao 2004 Condie & Selverstone 1999 Mekong River Particulates 73 Ta 1.35           µg/g Martin & Meybeck 1979 Middle Continental Crust 73 Ta 1.8           µg/g Rudnick & Gao 2004 Shaw et al. 1994 Middle Continental Crust 73 Ta 0.6           µg/g Rudnick & Gao 2004 Rudnick & Fountain 1995 Middle Continental Crust 73 Ta 0.6   0.04       µg/g Rudnick & Gao 2004 Middle Continental Crust 73 Ta 0.55           µg/g Rudnick & Gao 2004 Gao et al. 1998 Parana River Particulates 73 Ta 1.1           µg/g Martin & Meybeck 1979 River Particulates 73 Ta 1.25           µg/g Martin & Meybeck 1979 Silicate Earth 73 Ta 0.037           µg/g McDonough 1998 Solid Earth 73 Ta 0.025           µg/g McDonough 1998 Upper Continental Crust 73 Ta 0.79           µg/g Rudnick & Gao 2004 Condie 1993 Upper Continental Crust 73 Ta 0.74           µg/g Rudnick & Gao 2004 Gao et al. 1998 Upper Continental Crust 73 Ta 0.96           µg/g Rudnick & Gao 2004 Plank & Langmuir 1998 Upper Continental Crust 73 Ta 0.9           µg/g Rudnick & Gao 2004 Upper Continental Crust 73 Ta 1.5           µg/g Rudnick & Gao 2004 Wedepohl 1995 Upper Continental Crust 73 Ta 0.9   0.1       µg/g Rudnick & Gao 2004 see text Upper Continental Crust 73 Ta 5.7           µg/g Rudnick & Gao 2004 Shaw et al. 1967 Shaw et al. 1976 Upper Continental Crust 73 Ta 1           µg/g Rudnick & Gao 2004 Taylor & McLennan 1985 Taylor & McLennan 1995 Oceans Surface water 73 Ta         2.5   ng/kg Quinby-Hunt & Turekian 1983 Schutz & Turekian 1965 Seawater 73 Ta         2.5   ng/kg Quinby-Hunt & Turekian 1983 Schutz & Turekian 1965 Seawater 73 Ta         2.5     Li 1991 Whitfield & Turner 1987 Bruland 1983 Seawater 73 Ta         1.4e-05     Broeker & Peng 1982 Antilles Trench   Nb/Ta 16.4         3   Plank & Langmuir 1998 Stolz et al. 1996 Carbonate Turbidites   Nb/Ta 11.9   1.1     8   Plank & Langmuir 1998 Central East China Craton   Nb/Ta 19.5             Gao et al. 1998 Central East China Craton   Nb/Ta 17.5             Gao et al. 1998 Central East China Craton   Nb/Ta 17.4             Gao et al. 1998 Central East China Craton   Nb/Ta 16.5             Gao et al. 1998 Central East China Craton   Nb/Ta 16.7             Gao et al. 1998 Central East China Craton   Nb/Ta 17.9             Gao et al. 1998 Central East China Craton   Nb/Ta 17.3             Gao et al. 1998 Central East China Craton   Nb/Ta 14.7             Gao et al. 1998 CI Chondrites   Nb/Ta 17.6             McDonough 1990 McDonough & Frey 1989 Sun & McDonough 1989 Sun 1982 Continental Crust   Be/Ta 2.7             Salters & Stracke 2004 Depleted D-MORB basalts   Nb/Ta 15.19             Salters & Stracke 2004 Early Archean Upper Crust   La/Ta 42             Condie 1993 Early Archean Upper Crust   La/Ta 41             Condie 1993 Early Archean Upper Crust   Nb/Ta 12             Condie 1993 Early Archean Upper Crust   Nb/Ta 12             Condie 1993 Early Proterozoic Upper Crust   La/Ta 33             Condie 1993 Early Proterozoic Upper Crust   La/Ta 33             Condie 1993 Early Proterozoic Upper Crust   Nb/Ta 13             Condie 1993 Early Proterozoic Upper Crust   Nb/Ta 13             Condie 1993 Fresh Mid-Ocean Ridge Basalts   Nb/Ta 14.73             Salters & Stracke 2004 Late Archean Upper Crust   La/Ta 42             Condie 1993 Late Archean Upper Crust   La/Ta 43             Condie 1993 Late Archean Upper Crust   Nb/Ta 12             Condie 1993 Late Archean Upper Crust   Nb/Ta 12             Condie 1993 Late Proterozoic Upper Crust   La/Ta 32             Condie 1993 Late Proterozoic Upper Crust   La/Ta 32             Condie 1993 Late Proterozoic Upper Crust   Nb/Ta 13             Condie 1993 Late Proterozoic Upper Crust   Nb/Ta 13             Condie 1993 Mesozoic & Cenozoic Upper Crust   La/Ta 28             Condie 1993 Mesozoic & Cenozoic Upper Crust   La/Ta 28             Condie 1993 Mesozoic & Cenozoic Upper Crust   Nb/Ta 13             Condie 1993 Mesozoic & Cenozoic Upper Crust   Nb/Ta 13             Condie 1993 Middle Proterozoic Upper Crust   La/Ta 32             Condie 1993 Middle Proterozoic Upper Crust   La/Ta 33             Condie 1993 Middle Proterozoic Upper Crust   Nb/Ta 13             Condie 1993 Middle Proterozoic Upper Crust   Nb/Ta 13             Condie 1993 Paleozoic Upper Crust   La/Ta 28             Condie 1993 Paleozoic Upper Crust   La/Ta 28             Condie 1993 Paleozoic Upper Crust   Nb/Ta 13             Condie 1993 Paleozoic Upper Crust   Nb/Ta 13             Condie 1993 Pelagic Clay   Nb/Ta 21.8   4.3     9   Plank & Langmuir 1998 Pelagic Clay   Nb/Ta 12.6   1.6     7   Plank & Langmuir 1998 Primitive Mantle   Nb/Ta 17.6             Gao et al. 1998 Hofmann 1988 Primitive Mantle   Nb/Ta 17.6             McDonough 1990 McDonough & Frey 1989 Sun & McDonough 1989 Sun 1982 Radiolarites   Nb/Ta 15.5   2.9     7   Plank & Langmuir 1998 Red Clay   Nb/Ta 15.3         1   Plank & Langmuir 1998 Spinel Peridotites   Nb/Ta 17 17 3     4   McDonough 1990 Subducted Sediment   Nb/Ta 14.2   1.8     50   Plank & Langmuir 1998 Terrigenous Sediments   Nb/Ta 13.5   2.4     15   Plank & Langmuir 1998 Upper Continental Crust   La/Ta 35             Condie 1993 Upper Continental Crust   La/Ta 36             Condie 1993 Upper Continental Crust   Nb/Ta 12             Condie 1993 Upper Continental Crust   Nb/Ta 13             Condie 1993