메뉴 건너뛰기




Volumn 20, Issue SPL.ISS. 1, 2007, Pages 116-127

Back-arc basins

Author keywords

[No Author keywords available]

Indexed keywords


EID: 60249095540     PISSN: 10428275     EISSN: None     Source Type: Journal    
DOI: 10.5670/oceanog.2007.85     Document Type: Article
Times cited : (43)

References (61)
  • 1
    • 33646843809 scopus 로고    scopus 로고
    • Abundant hydrothermal venting along melt-rich and melt-free ridge segments in the Lau back-arc basin
    • doi:10.1029/2005GL025516
    • Baker, E.T., J.A. Resing, S.L. Walker, F. Martinez, B. Taylor, and K.-i. Nakamura. 2006. Abundant hydrothermal venting along melt-rich and melt-free ridge segments in the Lau back-arc basin. Geophysical Research Letters 33(7). doi:10.1029/2005GL025516.
    • (2006) Geophysical Research Letters , vol.33 , Issue.7
    • Baker, E.T.1    Resing, J.A.2    Walker, S.L.3    Martinez, F.B.4    Taylor5    Nakamura, K.-I.6
  • 3
    • 0019998597 scopus 로고
    • Black smokers fuelled by freezing magma
    • Cann, J.R., and M.R. Strens. 1982. Black smokers fuelled by freezing magma. Nature 298(5870):147-149.
    • (1982) Nature , vol.298 , Issue.5870 , pp. 147-149
    • Cann, J.R.1    Strens, M.R.2
  • 4
    • 0037055372 scopus 로고    scopus 로고
    • Structure and structural development of the Havre Trough (SW Pacific)
    • doi:10.1029/ 2001JB000494
    • Delteil, J., E. Ruellan, I. Wright, and T. Matsumoto. 2002. Structure and structural development of the Havre Trough (SW Pacific). Journal of Geophysical Research 107. doi:10.1029/ 2001JB000494.
    • (2002) Journal of Geophysical Research , pp. 107
    • Delteil, J.1    Ruellan, E.2    Wright, I.3    Matsumoto, T.4
  • 5
    • 0028175148 scopus 로고
    • Deep-sea hydrothermal communities in southwestern Pacific back-arc basins (the North Fiji and Lau Basins): Composition, microdistribution and food web
    • Desbruyères, D., A.M. Alayse-Danet, and S. Ohta. 1994. Deep-sea hydrothermal communities in southwestern Pacific back-arc basins (the North Fiji and Lau Basins): Composition, microdistribution and food web. Marine Geology 116:227-242.
    • (1994) Marine Geology , vol.116 , pp. 227-242
    • Desbruyères, D.1    Alayse-Danet, A.M.2    Ohta, S.3
  • 6
    • 71749108297 scopus 로고    scopus 로고
    • Asymmetric Accretion Along the Slow-spreading Mariana Ridge
    • Geophysics, Geosystems, doi:10.1029/2003GC000537
    • Deschamps, A., and T. Fujiwara. 2003. Asymmetric accretion along the slow-spreading Mariana Ridge. Geochemistry, Geophysics, Geosystems 4. doi:10.1029/2003GC000537.
    • (2003) Geochemistry, Geophysics, Geosystems , pp. 4
    • Deschamps, A.1    Fujiwara, T.2
  • 7
    • 0015020331 scopus 로고
    • Sea-floor spreading as thermal convection
    • Elsasser, W.M. 1971. Sea-floor spreading as thermal convection. Journal of Geophysical Research 76:1,101-1,112.
    • (1971) Journal of Geophysical Research , vol.76-112 , Issue.1 , pp. 101
    • Elsasser, W.M.1
  • 9
    • 0031972176 scopus 로고    scopus 로고
    • Chemical and isotopic composition of lavas from the northern Mariana Trough: Implications for magmagenesis in back-arc basin
    • Gribble, R.F., R.J. Stern, S. Newman, S.H. Blommer, and T. O'Hearn. 1998. Chemical and isotopic composition of lavas from the northern Mariana Trough: Implications for magmagenesis in back-arc basin. Journal of Petrology 39:125-154.
    • (1998) Journal of Petrology , vol.39 , pp. 125-154
    • Gribble, R.F.1    Stern, R.J.2    Newman, S.3    Blommer, S.H.4    O'Hearn, T.5
  • 12
    • 0032505295 scopus 로고    scopus 로고
    • Origin of the Indian Ocean-type isotopic signature in basalts from Philippine Sea plate spreading centers: An assessment of local versus large scale processes
    • 963-20
    • Hickey-Vargas, R. 1998. Origin of the Indian Ocean-type isotopic signature in basalts from Philippine Sea plate spreading centers: An assessment of local versus large scale processes. Journal of Geophysical Research 103:20,963-20,979.
    • (1998) Journal of Geophysical Research , vol.103 , Issue.20
    • Hickey-Vargas, R.1
  • 13
    • 0345328152 scopus 로고    scopus 로고
    • Sulfurimonas autotrophica gen. nov., sp. nov., a novel sulfur-oxidizing E-proteobacterium isolated from hydrothermal sediments in the Mid-Okinawa Trough
    • Inagaki, F., K. Takai, K. Nealson, and K. Horikoshi. 2003. Sulfurimonas autotrophica gen. nov., sp. nov., a novel sulfur-oxidizing E-proteobacterium isolated from hydrothermal sediments in the Mid-Okinawa Trough. International Journal of Systematic Evolutionary Microbiology 53:1,801-1,805.
    • (2003) International Journal of Systematic Evolutionary Microbiology , vol.53 , Issue.1 , pp. 801
    • Inagaki, F.1    Takai, K.2    Nealson, K.3    Horikoshi, K.4
  • 14
    • 5444247841 scopus 로고    scopus 로고
    • Sulfurovum lithotrophicum gen. nov., sp. nov., a novel sulfur-oxidizing chemolithoautotroph within the x3B5;-Proteobacteria isolated from Okinawa Trough hydrothermal sediments
    • 477-471
    • Inagaki, F., K. Takai, K.H. Nealson, and K. Horikoshi. 2004. Sulfurovum lithotrophicum gen. nov., sp. nov., a novel sulfur-oxidizing chemolithoautotroph within the E-Proteobacteria isolated from Okinawa Trough hydrothermal sediments. International Journal of Systematic Evolutionary Microbiology 54:1,477-1,482.
    • (2004) International Journal of Systematic Evolutionary Microbiology , vol.54 , Issue.1
    • Inagaki, F.1    Takai, K.2    Nealson, K.H.3    Horikoshi, K.4
  • 16
    • 0002313397 scopus 로고
    • Hydrothermal activity related to arc-backarc magmatism in the western Pacific
    • B. Taylor, ed, Plenum Press, New York
    • Ishibashi, J., and T. Urabe. 1995. Hydrothermal activity related to arc-backarc magmatism in the western Pacific. Pp. 451-495 in Backarc Basins: Tectonics and Magmatism. B. Taylor, ed, Plenum Press, New York.
    • (1995) Backarc Basins: Tectonics and Magmatism , pp. 451-495
    • Ishibashi, J.1    Urabe, T.2
  • 17
    • 0000663140 scopus 로고
    • Ridges and basins of the Tonga-Kermadec island arc system
    • Karig, D.E. 1970. Ridges and basins of the Tonga-Kermadec island arc system. Journal of Geophysical Research 75:239-254.
    • (1970) Journal of Geophysical Research , vol.75 , pp. 239-254
    • Karig, D.E.1
  • 20
    • 0014329869 scopus 로고
    • Melting of a peridotite nodule at high pressures and high water pressures
    • Kushiro, I., Y. Syono, and S. Akimoto. 1968. Melting of a peridotite nodule at high pressures and high water pressures. Journal of Geophysical Research 73(18):6,023-6,029.
    • (1968) Journal of Geophysical Research , vol.73 , Issue.6 , pp. 023-026
    • Kushiro, I.1    Syono, Y.2    Akimoto, S.3
  • 21
    • 0000252496 scopus 로고
    • Petrological systematics of mid-ocean ridge basalts: Constraints on melt generation beneath ocean ridges
    • J. Phipps Morgan, D.K. Blackman, and J.M. Sinton, American Geophysical Union, Washington, DC
    • Langmuir, C.H., E.M. Klein, and T. Plank. 1992. Petrological systematics of mid-ocean ridge basalts: Constraints on melt generation beneath ocean ridges. Pp. 183-280 in Mantle Flow and Melt Generation at Mid-Ocean Ridges. J. Phipps Morgan, D.K. Blackman, and J.M. Sinton, eds, American Geophysical Union, Washington, DC.
    • (1992) Mantle Flow and Melt Generation At Mid-Ocean Ridges , pp. 183-280
    • Langmuir, C.H.1    Klein, E.M.2    Plank, T.3
  • 22
    • 0033857926 scopus 로고    scopus 로고
    • Susceptibility to heavy metals and cadmium accumulation in aerobic and anaerobic thermophilic microorganisms isolated from deep-sea hydrothermal vents
    • Llanos, J., C. Capasso, E. Parisi, D. Prieur, and C. Jeanthon. 2000. Susceptibility to heavy metals and cadmium accumulation in aerobic and anaerobic thermophilic microorganisms isolated from deep-sea hydrothermal vents. Current Microbiology 41:201-205.
    • (2000) Current Microbiology , vol.41 , pp. 201-205
    • Llanos, J.1    Capasso, C.2    Parisi, E.3    Prieur, D.4    Jeanthon, C.5
  • 23
    • 0034631624 scopus 로고    scopus 로고
    • Geophysical Characteristics of the Southern Mariana Trough, 11°50 ́N-13°40 ́N
    • 591-16
    • Martinez, F., P. Fryer, and N. Becker. 2000. Geophysical Characteristics of the Southern Mariana Trough, 11°50 ́N-13°40 ́N. Journal of Geophysical Research 105:16,591-16,607.
    • (2000) Journal of Geophysical Research , vol.105 , Issue.16
    • Martinez, F.1    Fryer, P.2    Becker, N.3
  • 24
    • 0037187595 scopus 로고    scopus 로고
    • Mantle wedge control on back-arc crustal accretion
    • Martinez, F., and B. Taylor. 2002. Mantle wedge control on back-arc crustal accretion. Nature 416:417-420.
    • (2002) Nature , vol.416 , pp. 417-420
    • Martinez, F.1    Taylor, B.2
  • 25
    • 0346651423 scopus 로고    scopus 로고
    • Controls on back-arc crustal accretion: Insights from the Lau, Manus and Mariana basins
    • R.D. Larter and P.T. Leat, eds, Geological Society of London Special Publications
    • Martinez, F., and B. Taylor. 2003. Controls on back-arc crustal accretion: Insights from the Lau, Manus and Mariana basins. Pp. 19-54 in Intra-Oceanic Subduction Systems: Tectonic and Magmatic Processes. R.D. Larter and P.T. Leat, eds, Geological Society of London Special Publications 219.
    • (2003) Intra-Oceanic Subduction Systems: Tectonic and Magmatic Processes , pp. 19-54
    • Martinez, F.1    Taylor, B.2
  • 26
    • 84951282373 scopus 로고    scopus 로고
    • Modes of crustal accretion in back-arc basins: Inferences from the Lau Basin
    • D.M. Christie, C.R. Fisher, S.-M. Lee, and S. Givens, eds, American Geophysical Union, Washington, DC
    • Martinez, F., and B. Taylor. 2006. Modes of crustal accretion in back-arc basins: Inferences from the Lau Basin. Pp. 5-30 in Back-Arc Spreading Systems: Geological, Biological, Chemical and Physical Interactions. D.M. Christie, C.R. Fisher, S.-M. Lee, and S. Givens, eds, American Geophysical Union, Washington, DC.
    • (2006) Back-Arc Spreading Systems: Geological, Biological, Chemical and Physical Interactions , pp. 5-30
    • Martinez, F.1    Taylor, B.2
  • 27
    • 33646511978 scopus 로고    scopus 로고
    • Opposing trends in crustal thickness and spreading rate along the back-arc Eastern Lau Spreading Center: Implications for controls on ridge morphology, faulting, and hydrothermal activity
    • Martinez, F., B. Taylor, E.T. Baker, J.A. Resing, and S.L. Walker. 2006. Opposing trends in crustal thickness and spreading rate along the back-arc Eastern Lau Spreading Center: Implications for controls on ridge morphology, faulting, and hydrothermal activity. Earth and Planetary Science Letters 245:655-672.
    • (2006) Earth and Planetary Science Letters , vol.245 , pp. 655-672
    • Martinez, F.1    Taylor, B.2    Baker, E.T.3    Resing, J.A.4    Walker, S.L.5
  • 29
    • 84880213717 scopus 로고
    • Origin of lithosphere behind island arcs, with reference to the western Pacific
    • R. Shagam, R.B. Hargrave, W.J. Morgan, F.B. Van Houten, C.A. Burk, H.D. Holland, and L.C. Hollister, eds, Geological Society of America, Boulder, Colorado
    • Moberly, R. 1972. Origin of lithosphere behind island arcs, with reference to the western Pacific. Pp. 35-55 in Studies in Earth and Space Sciences: A Memoir in Honor of Harry Hammond Hess, Memoir 132. R. Shagam, R.B. Hargrave, W.J. Morgan, F.B. Van Houten, C.A. Burk, H.D. Holland, and L.C. Hollister, eds, Geological Society of America, Boulder, Colorado.
    • (1972) Studies In Earth and Space Sciences: A Memoir In Honor of Harry Hammond Hess, Memoir , pp. 35-55
    • Moberly, R.1
  • 30
    • 0242297891 scopus 로고
    • Interarc spreading and Cordilleran tectonics as alternates related to the age of subducted oceanic lithosphere
    • Molnar, P., and T. Atwater. 1978. Interarc spreading and Cordilleran tectonics as alternates related to the age of subducted oceanic lithosphere. Earth and Planetary Science Letters 41:330-340.
    • (1978) Earth and Planetary Science Letters , vol.41 , pp. 330-340
    • Molnar, P.1    Atwater, T.2
  • 31
    • 16844381589 scopus 로고    scopus 로고
    • Thioreductor micantisoli gen. nov., sp. nov., a novel mesophilic, sulfur-reducing chemolithoautotroph within the E-Proteobacteria isolated from the hydrothermal sediments in the Mid-Okinawa Trough
    • Nakagawa, S., F. Inagaki, K. Takai, K. Horikoshi, and Y. Sako. 2005a. Thioreductor micantisoli gen. nov., sp. nov., a novel mesophilic, sulfur-reducing chemolithoautotroph within the E-Proteobacteria isolated from the hydrothermal sediments in the Mid-Okinawa Trough. International Journal of Systematic Evolutionary Microbiology 55:599-605.
    • (2005) International Journal of Systematic Evolutionary Microbiology , vol.55 , pp. 599-605
    • Nakagawa, S.1    Inagaki, F.2    Takai, K.3    Horikoshi, K.4    Sako, Y.5
  • 32
    • 16844387103 scopus 로고    scopus 로고
    • Nitratiruptor tergarcus gen. nov., sp. nov. and Nitratifractor salsuginis gen. nov., sp. nov., nitrate-reducing chemolithoautotrophs of the E-Proteobacteria isolated from a deep-sea hydrothermal system in the Mid-Okinawa Trough
    • Nakagawa, S., K. Takai, F. Inagaki, K. Horikoshi, and Y. Sako. 2005b. Nitratiruptor tergarcus gen. nov., sp. nov. and Nitratifractor salsuginis gen. nov., sp. nov., nitrate-reducing chemolithoautotrophs of the E-Proteobacteria isolated from a deep-sea hydrothermal system in the Mid-Okinawa Trough. International Journal of Systematic Evolutionary Microbiology 55:925-933.
    • (2005) International Journal of Systematic Evolutionary Microbiology , vol.55 , pp. 925-933
    • Nakagawa, S.1    Takai, K.2    Inagaki, F.3    Horikoshi, K.4    Sako, Y.5
  • 33
    • 0042806107 scopus 로고    scopus 로고
    • A new genus and species of barnacle (Cirripedia, Verrucomorpha) associated with vents of the Lau Back-Arc Basin: Its gross morphology, inferred first juvenile stage and affinities
    • Newman, W.A. 2000. A new genus and species of barnacle (Cirripedia, Verrucomorpha) associated with vents of the Lau Back-Arc Basin: Its gross morphology, inferred first juvenile stage and affinities. Zoosystema 22(1):71-84.
    • (2000) Zoosystema , vol.22 , Issue.1 , pp. 71-84
    • Newman, W.A.1
  • 34
    • 0009386671 scopus 로고
    • A new sessile barnacle (Cirripedia, Brachylepadomorpha) from the Lau-Arc Basin, Tonga; first record of a living representative since the Miocene
    • 4e serie. Section A. Zoologie biologie: et ecologie animales. Paris
    • Newman, W.A., and T. Yamaguchi. 1995. A new sessile barnacle (Cirripedia, Brachylepadomorpha) from the Lau-Arc Basin, Tonga; first record of a living representative since the Miocene. Bulletin du Muséum national d'Histoire naturelle (France). 4e serie. Section A. Zoologie biologie: et ecologie animales. Paris, 17:221-243.
    • (1995) Bulletin Du Muséum National D'Histoire Naturelle (France) , vol.17 , pp. 221-243
    • Newman, W.A.1    Yamaguchi, T.2
  • 36
    • 33644782198 scopus 로고    scopus 로고
    • Peridotites and Gabbros From the Parece Vela Backarc Basin: Unique Tectonic Window In An Extinct Backarc Spreading Ridge
    • doi: 10.1029/2002GC000469
    • Ohara, Y., K. Fujioka, T. Ishii, and H. Yurimoto. 2003. Peridotites and gabbros from the Parece Vela backarc basin: Unique tectonic window in an extinct backarc spreading ridge. Geochemistry, Geophysics, Geosystems 4. doi: 10.1029/2002GC000469.
    • (2003) Geochemistry Geophysics, Geosystems , pp. 4
    • Ohara, Y.1    Fujioka, K.2    Ishii, T.3    Yurimoto, H.4
  • 37
    • 33644802606 scopus 로고    scopus 로고
    • Mantle process beneath Philippine Sea back-arc spreading ridges: A synthesis of peridotite petrology and tectonics
    • Ohara, Y. 2006. Mantle process beneath Philippine Sea back-arc spreading ridges: A synthesis of peridotite petrology and tectonics. Island Arc 15:119-129.
    • (2006) Island Arc , vol.15 , pp. 119-129
    • Ohara, Y.1
  • 39
    • 0033452280 scopus 로고    scopus 로고
    • The Philippine Sea: New survey results reveal the structure and the history of the marginal basins
    • 287-282
    • Okino, K., Y. Ohara, S. Kasuga, and Y. Kato. 1999. The Philippine Sea: New survey results reveal the structure and the history of the marginal basins. Geophysical Research Letters 26:2,287-2,290.
    • (1999) Geophysical Research Letters , vol.26 , Issue.2
    • Okino, K.1    Ohara, Y.2    Kasuga, S.3    Kato, Y.4
  • 42
    • 0030456632 scopus 로고    scopus 로고
    • Fatty acid characteristics in two symbiotic gastropods from a deep hydrothermal vent of the West Pacific
    • Pranal V., A. Fiala-Médioni, and J. Guezennec. 1996. Fatty acid characteristics in two symbiotic gastropods from a deep hydrothermal vent of the West Pacific. Marine Ecology Progress Series 142:175-184.
    • (1996) Marine Ecology Progress Series , vol.142 , pp. 175-184
    • Pranal, V.1    Fiala-Médioni, A.2    Guezennec, J.3
  • 43
    • 0036920285 scopus 로고    scopus 로고
    • Expanding the distribution of the Aquificales to the deep-sea vents on Mid-Atlantic Ridge and Central Indian Ridge
    • Reysenbach, A.-L., D. Gotz, A. Banta, C. Jeanthon, and Y. Fouquet. 2002. Expanding the distribution of the Aquificales to the deep-sea vents on Mid-Atlantic Ridge and Central Indian Ridge. Cahiers de Biologie Marine 43:425-428.
    • (2002) Cahiers De Biologie Marine , vol.43 , pp. 425-428
    • Reysenbach, A.-L.1    Gotz, D.2    Banta, A.3    Jeanthon, C.4    Fouquet, Y.5
  • 45
    • 0036400033 scopus 로고    scopus 로고
    • Geochemical and isotopic characteristics of the Kinan Seamount Chain in the Shikoku Basin
    • Sato, H., S. Machida, S. Kanayama, H. Taniguchi, and T. Ishii. 2002. Geochemical and isotopic characteristics of the Kinan Seamount Chain in the Shikoku Basin. Geochemical Journal 36:519-526.
    • (2002) Geochemical Journal , vol.36 , pp. 519-526
    • Sato, H.1    Machida, S.2    Kanayama, S.3    Taniguchi, H.4    Ishii, T.5
  • 46
    • 0032448179 scopus 로고    scopus 로고
    • Experimentally based water budgets for dehydrating slabs and consequences for arc magma generation
    • Schmidt, M.W., and S. Poli. 1998. Experimentally based water budgets for dehydrating slabs and consequences for arc magma generation. Earth and Planetary Science Letters 163:361-379.
    • (1998) Earth and Planetary Science Letters , vol.163 , pp. 361-379
    • Schmidt, M.W.1    Poli, S.2
  • 47
    • 0029540342 scopus 로고
    • On the mechanism of seismic decoupling and back arc spreading at subduction zones
    • Scholz, C.H., and J. Campos. 1995. On the mechanism of seismic decoupling and back arc spreading at subduction zones. Journal of Geophysical Research 100:22,103-22,115.
    • (1995) Journal of Geophysical Research , vol.100 , Issue.22 , pp. 103-122
    • Scholz, C.H.1    Campos, J.2
  • 48
    • 0037245787 scopus 로고    scopus 로고
    • Magma genesis and mantle heterogeneity in the Manus back-arc basin, Papua New Guinea
    • Sinton, J.M., L. Ford, B. Chappell, and M. Mc-Culloch. 2003. Magma genesis and mantle heterogeneity in the Manus back-arc basin, Papua New Guinea. Journal of Petrology 44:159-195.
    • (2003) Journal of Petrology , vol.44 , pp. 159-195
    • Sinton, J.M.1    Ford, L.2    Chappell, B.3    Mc-Culloch, M.4
  • 49
    • 0030620654 scopus 로고    scopus 로고
    • A new vestimentiferan (Pogonophora: Obturata) from hydrothermal vent fields in the Manus Backarc Basin (Bismarck Sea, Papua New Guinea, Southwest Pacific Ocean)
    • Southward, E.C., and S.V. Galkin. 1997. A new vestimentiferan (Pogonophora: Obturata) from hydrothermal vent fields in the Manus Backarc Basin (Bismarck Sea, Papua New Guinea, Southwest Pacific Ocean). Journal of Natural History 31:43-55.
    • (1997) Journal of Natural History , vol.31 , pp. 43-55
    • Southward, E.C.1    Galkin, S.V.2
  • 50
    • 0021593567 scopus 로고
    • Unzipping of the Volcano Arc, Japan
    • Stern, R.J., N.C. Smoot, and M. Rubin. 1984. Unzipping of the Volcano Arc, Japan. Tectonophysics 102:153-174.
    • (1984) Tectonophysics , vol.102 , pp. 153-174
    • Stern, R.J.1    Smoot, N.C.2    Rubin, M.3
  • 54
    • 84989573793 scopus 로고
    • Formation of the volcanic front in subduction zones
    • Tatsumi, Y. 1986. Formation of the volcanic front in subduction zones. Geophysical Research Letters 13:717-720.
    • (1986) Geophysical Research Letters , vol.13 , pp. 717-720
    • Tatsumi, Y.1
  • 60
    • 0000011146 scopus 로고    scopus 로고
    • The hydrothermal vent barnacle Eochionelasmus (Cirripedia, Balanomorpha) from the North Fiji, Lau and Manus Basins
    • Yamaguchi, T., and W.A. Newman. 1997. The hydrothermal vent barnacle Eochionelasmus (Cirripedia, Balanomorpha) from the North Fiji, Lau and Manus Basins, South-West Pacific. Zoosystema 19:623-649.
    • (1997) South-West Pacific. Zoosystema , vol.19 , pp. 623-649
    • Yamaguchi, T.1    Newman, W.A.2
  • 61
    • 0003370910 scopus 로고    scopus 로고
    • A threeplate kinematic model for Lau Basin opening
    • doi:10.1029/2000GC000106
    • Zellmer, K.E., and B. Taylor. 2001. A threeplate kinematic model for Lau Basin opening. Geochemistry, Geophysics, Geosystems 2,. doi:10.1029/2000GC000106.
    • (2001) Geochemistry, Geophysics, Geosystems , pp. 2
    • Zellmer, K.E.1    Taylor, B.2


* 이 정보는 Elsevier사의 SCOPUS DB에서 KISTI가 분석하여 추출한 것입니다.