台灣西南海域的海床上分佈著許多甲烷逸散的噴氣口，過去研究大都使用重力式和活塞式岩心採樣器採樣，再估算噴氣海域之溶解甲烷溢出量，但由於定位困難與海洋研究船缺少動態定位系統，傳統的岩心採樣之點位與聲納偵測的噴氣點位可能無法吻合，導致無法精準在逸氣點附近採得水體及沉積物樣品，因此測出的甲烷濃度可能無法反應真實數據，這也會影響溶解甲烷溢出通量的估算。本研究使用國立中山大學水下機電實驗室開發的拖曳式水下攝影機搭載多管柱岩心採集器，根據回傳的即時海底沉積物噴氣影像後立即採樣。本研究於2014年在台灣西南海域不同海洋地質環境採集逸氣點的近海底水樣及表層沉積物樣品，並測量樣品中之甲烷、硫酸鹽濃度及溶解態無機碳和有機碳濃度(dissolved organic carbon, DOC)，以估算甲烷及DOC從沉積物擴散到底水的通量。
結果顯示表層沉積物最高的甲烷濃度(128452 nM)是出現在泥火山區之MV1，其次是TY1(63128 nM)和G96(12210 nM)，上覆海水之甲烷濃度則呈現很大的變化(從60至2421 nM)。以擴散公式估算沉積物至底水之甲烷擴散通量在海底泥火山區、四方圈合冷泉區及好景海脊之甲烷擴散通量分別為 47.5 ~ 47883.4、95.1~ 99.1 及119.4 ~194.1 μmol m-2 d-1。本研究得到甲烷通量由於採樣方式的不同，低於世界其他海域不同泥火山和冷泉區域約2~3個數量級(以無人載具搭配水底集氣裝置，約0.25~1226 mmol m-2 d-1)，但遠高於過去學者在此海域的估計值(1.1~157 μmol m-2 d-1)。因多管束岩心採集器的樣品長度較短，要在沉積物觀察到甲烷和硫酸鹽濃度趨勢以及sulfate-methane interface (SMI)的深度機率較低，本研究岩心採集深度離天然氣水合物賦存層深度仍有較長的距離。DOC濃度在海水剖面底部也能看出有升高的趨勢，表示有一部分的DOC可能來自於海底冷泉或泥火山。估算表層沉積物到底層海水的DOC擴散通量為約53~2100 μmol m-2 d-1，遠高於過去利用一般岩心採樣器所估算的DOC擴散通量(約33~196 μmol m-2 d-1)。
本研究觀測到最高的甲烷及DOC通量都要比以前學者於該區域的結果分別要高出2及1個數量級，顯示即時攝影採樣系統可能更準確的貼近泥火山之噴氣逸散區。

Many natural methane seeps exist in waters offshore southwestern (SW) Taiwan. Researchers have frequently used gravity and piston corers to collect sediments and bottom seawater for estimating methane fluxes of these seeps. Due to the difficulty in positioning of the piston and gravity corers when sampling at sea, the actual sampling locations of these corers are difficult to match seeping vents detected by scientific echo sounder. Thus, the methane fluxes of the seeping vents estimated using these corers might not be representative methane fluxes of seeping vents off SW Taiwan. In this study, we used a real-time video multiple-corer that was designed by Underwater Mechatronics Lab, National Sun Yat-sen University (UML, NSYSU) to collect sediments and bottom seawater samples. This real-time multi-corer can precisely obtain sediments and bottom seawater samples on methane seeping vents. We analyzed the concentration of methane, anion, dissolved inorganic carbon and dissolved organic carbon in these samples and estimated methane and DOC fluxes, respectively.
The highest methane concentration in sediment has measured at MV1 (128,452 nM), next to TY1 (63,128 nM) and G96 (12,210 nM) in mud volcanoes area, and the methane concentration in core-top water were 59.8 to 2421.1 nM, respectively. Based on Fick’s First Law, methane flux from sediment to bottom water in mud volcanoes area, Four-way Closure Ridge (FWCR) cold seep area, and Good Weather Ridge (GWR) were 47.5 to 47883.4、95.1 to 99.1, and 119.4 to 194.1 μmol m−2 d−1, respectively. Comparison of our values from SW Taiwan and previously reported data around the world, our results are two to three orders of magnitude lower than those reported values(using ROV with benthic chamber, ca. 0.25~1226 mmol m-2 d-1) in different mud volcanoes and seeps, but higher than previously reported values (1.1~157 μmol m-2 d-1). Because the samples collected by multiple-corer were shallow, the corer did not reach the sulfate-methane interface (SMI) in this study. In addition to, the coring depth was far away from gas hydrate bearing zone. Elevated DOC concentrations at the bottom depths were found at some sites suggesting that some of DOC may come from seeps or mud volcanoes. The DOC benthic flux from sediment to bottom water were 53 to 2100 μmol m-2 d-1, which are higher than previously reported data (using normal corer, ca. 33~196 μmol m-2 d-1).
In summary, the fluxes of methane and DOC in the SW Taiwan are two and one orders of magnitude higher than those of previous studies in similar area respectively, indicating that the real-time multiple-corer can be used for more precisely obtaining sediments and bottom seawater samples on methane seeping vents.

致謝 i
摘要 ii
Abstract iv
圖目錄 viii
表目錄 x
壹、前言 1
貳、研究目的 6
2-1 測量逸氣構造樣品之參數 6
2-2 探討逸氣構造沉積物之硫酸鹽和有機碳 6
2-3 探討逸氣構造海水剖面之溶解態無機碳和有機碳 7
叁、研究區域及方法 10
3-1 研究區域 10
3-2 研究區域地質構造 12
3-3 樣品與分析方法 18
3-3-1 海洋沉積物採集與分析 18
3-3-2 海水樣品採集與分析 19
3-4 甲烷樣品分析 22
肆、結果與討論 23
4-1 海水樣品分析結果 23
4-1-1海水溶解甲烷濃度(CH4)分析結果 23
4-1-2 溶解態有機碳濃度(DOC)在水體之分布 28
4-1-3 南海北部海水溶解態無機碳濃度(DIC)、鹼度(TA)和二氧化碳分 壓(fCO2)之垂直分布 34
4-2 沉積物樣品分析結果 42
4-3 甲烷擴散通量之探討 61
4-4 溫度對甲烷溶解度之探討 63
4-5 淺層沉積物對海洋底水混合之探討 65
伍、結論 67
陸、參考文獻 69

洪瑋立（2009）台灣西南部地區增積岩楔之甲烷貢獻量評估。國立台灣大學地質科學研究所碩士論文，共88頁。
胡靜宜（2012）台灣西南海域天然氣水合物潛藏區甲烷通量與流體來源探討。國立台灣大學地質科學研究所碩士論文，共80頁。
施詠嚴（2005）南海時間序列測站2002-2004年間溶解態無機碳之時序變化：淨族群生產力之評估。國立中山大學海洋地質及化學研究所碩士論文，共68頁。
陳乃禎、黃愉珺、陳宣文、林曉武、王詠絢、楊燦堯（2015）台灣西南海域天然氣水合物賦存區海洋沉積物之甲烷通量估算。103年天然氣水合物分項成果發表會，論文集第56頁。
陳松春（2011）台灣西南海域高屏上部斜坡之逸氣構造和天然氣水合物賦存關係之研究。經濟部中央地質調查所報告書100年度自行研究計畫報告編號100008，共112頁。
陳松春（2013）臺灣西南海域上部高屏斜坡泥貫入體及泥火山之分布及相關海床特徵。國立中央大學地球科學學系博士論文，共116頁。
陳宣文（2011）台灣西南海域沉積物孔隙水之地球化學研究與其來源之探討。國立台灣大學地質科學研究所碩士論文，共69頁。
莊佩涓（2006）台灣西南海域天然氣水合物賦存區之氣體地球化學研究。國立台灣大學地質科學研究所碩士論文，共83頁。
黃愉珺（2013）台南西南海域上部斜坡海底泥火山氣體來源及甲烷通量估算。國立台灣大學地質科學研究所碩士論文，共79頁。
張裕彰（2010）台灣島上及周遭水域之CH4分佈。國立中山大學海洋地質及化 學研究所碩士論文，共144頁。
楊燦堯、陳乃禎、莊佩涓、陳宣文、林曉武、孫智賢、鐘三雄、王詠絢（2011），台灣西南海域天然氣水合物賦存區之氣體來源探討。2011 天然氣水合物調查研究成果研討會，論文摘要集第16-19頁。
謝偉琦（2006）台灣西南海域沉積物之硫酸鹽還原作用與甲烷擴散之關係。國立台灣大學海洋研究所碩士論文，共60頁。
鐘三雄、張碩芳（2001）甲烷氣水包合物的研究調查回顧與展望。經濟部中央地質調查所彙刊，第14號，第35-82頁。

Alperin M. J., Albert D. B., and Martens C. S. (1994) Seasonal variations in production and consumption rates of dissolved organic carbon in an organic-rich coastal sediment. Geochimica et Cosmochimica Acta , 58, 4909–4929.
Berner, R. A. (1980) Early Diagenesis. A Theoretical Approach. Princeton University Press, 241pp.
Boetius, A. and Wenzhöfer, F. (2013) Seafloor oxygen consumption fuelled by methane from cold seeps. Nature Geoscience, 6, 725–734
Borowski, W. S., Paull, C. K., and Ussler III, W. (1996) Marine pore-water sulfate profiles indicate in situ methane flux from underlying gas hydrate. Geology, 24(7), 655–658
Carlson, C. A. (2002) Production and removal processes. In: Biogeochemistry of Marine Dissolved Organic Matter. Ed: Hansell, D. A., Carlson, C. A., Academic Press, USA., 91-151.
Chen, C. T. A. and Tseng, H. C. (2006) Abnormally high CH4 concentrations in seawater at mid-depths on the continental slopes of the northern South China Sea. Terrestrial, Atmospheric and Oceanic Sciences, 17, 951-959.
Chi, W. C., Reed, D. L., Liu, C. S. , and Lunberg, N. (1998) Distribution of the bottom simulating reflector in the offshore Taiwan collision zone. Terrest`rial, Atmospheric and Oceanic Sciences, 9, 779-793.
Chuang, P. C., Dale, A. W., Wallmann, K., Haeckel, M., Yang, T. F., Chen, N. C., Chen, H. C., Chen, H. W., Lin, S., Sun, C. H., You, C. F., Horng, C. S., Wang, Y., and Chung, S. H. (2013) Relating sulfate and methane dynamics to geology : Accretionary prism offshore SW Taiwan. Geochemistry, Geophysics, Geo-systems, 14, 2523-2545.
Chuang, P. C., Yang, T. F., Hong, W. L., Lin, S., Sun, C. H., Lin, A. T. S., Chen, J. C., Wang, Y., and Chung, S. H. (2010) Estimation of methane flux offshore SW Taiwan and the influence of tectonics on gas hydrate accumulation, Geofluids, 10(4), 497-510.
Chuang, P. C., Yang, T. F., Lin, S., Lee, H. F., Lan, T. F., Hong, W. L., Liu, C. S., Chen J. C., and Wang, Y. (2006) Extremely high methane concentration in bottom water and cored sediments from offshore Southwestern Taiwan. Terrestrial, Atmospheric and Oceanic Sciences, 17, 903-920.
Copin-Montégut, G., Avril, B. (1993) Vertical distributions and temporal variation of dissolved organic carbon in the North Western Mediterranean Sea. Deep-Sea Research I 40, 1963–1972
Davidson, D. W. (1983) Gas hydrates as clathrate ices. In: Cox, J.L. (Ed) Natural Gas Hydrates, Properties, Occurrence, and Recovery. Butterworth, Woburn, MS., 1-16.
de Angelis, M. A. and C. Lee, (1994) Methane production during zooplankton grazing on marine phytoplankton. Limnology and Oceanography, 39, 1298-1308.
Dittmar, T. and Koch, B. P. (2006) Thermogenic organic matter dissolved in the abyssal ocean. Marine Chemistry 102, 208–217.
Doval, M.D., Álverez-Salgado, X.A., Pérez, F. F. (2001) Organic matter distributions in the Eastern North Atlantic-Azores Front region. Journal of Marine Systems 30, 33–49.
Felden, J., Wenzhöfer, F., Feseker, T., and Boetius, A. (2010) Transport and consum-ption of oxygen and methane in different habitats of the Håkon Mosby mud volcano (HMMV). Limnology and Oceanography. 55, 2366–2380.
Felden, J., Lichtschlag, A., Wenzhöfer, F., de Beer, D., Feseker, T., Pop Ristova, P., de Lange, G., and Boetius, A. (2013) Limitations of microbial hydrocarbon de-gradation at the Amon mud volcano (Nile deep sea fan). Biogeosciences 10, 3269–3283.
Hedges, J. I. (1992) Global biogeochemical cycles – progress and problems. Marine Chemistry, 39(1-3)：67-93.
Ho, C. Y. and Hung, C. C. (2014) Dissolved organic carbon fluxes of sediments from the northern South China Sea. 2014 17th Ocean Sciences Meeting, P.158.
Hsu, S. K., Wang, S. Y., Liao, Y. C., Yang, T. F., Jan, S., Lin, J. Y., and Chen, S. C. (2013) Tide-modulated gas emissions and tremors off SW Taiwan. Earth and Planetary Science Letters, 369-370, 98-107.
Iversen, N. and Jørgensen, B. B. (1993) Diffusion coefficients of sulfate and methane in marine sediments: Influence of porosity. Geochimica et Cosmochimica Acta, 57, 571-578.
Karl, D. M. and B. D. Tilbrook, 1994: Production and transport of methane in oceanic particulate organic matter. Nature, 368, 732-734.
Kennicutt, M. C., Brooks, J. M., Bidigare, R. R., Fay, R. R., Wade, T. L., and MacDonald, T.J. (1985) Vent-type taxa in a hydrocarbon seep region on the Louisiana slope. Nature, 317, 351-353
Kvenvolden, K. A. (1993) Gas hydrates–geological perspective and global change.
Reviews of Geophysics, 31, 173-187
Kvenvolden, K. A. (1998) A primer on the geological occurrence of gas hydrate. In: Gas hydrates: relevance to world margin stability and climate change, Henriet, J. P. and Mienert, J. (Eds.) Geological Society of London, Spec. Publ., 137, 9-30
Kvenvolden, K. A. and Grantz, A. (1990) Gas hydrates of the Arctic Ocean region. In: Grantz, A., Johnson, L. and Sweeney, J. (Eds.) The Geology of North America. Vol. L – The Arctic Ocean Region. Geological Society of America, Boulder, CO., 539-549.
Kvenvolden, K. A. and Barnard, L. A. (1983) Gas hydrates of the Blake Outer Ridge, Site 533, Deep Sea Drilling Project Leg 76. In: Sheridan, R.E., Gradstein, F.M., et al. (Eds.) Initial Reports of the Deep Sea Drilling Project, 76, 353-365.
Lewis, E., Wallace, D. W. R., (1998) Program developed for CO2 system calculations report Oak Ridge Natl. Lab., Dep. Of Energy, Oak Ridge, Tenn., 105, 33pp. (Available at http;//cdiac.esd.oml.gov/oceans/co2rprt.html)
Liu, C. S., Schnurle, P., Wang, Y. , Chung, S. H., Chen, S. C., and Hsiuan, T. H. (2006) Distribution and characters of gas hydrate offshore of southwestern Taiwan. Terrestrial, Atmospheric and Oceanic Sciences, 17, 615-644.
Matsumoto, R. (1995) Crystal structure and physical properties of methane hydrate. Petrotec, 18, 27-32.
Mörner, N. A. and Etiope, G. (2002) Carbon degassing from the lithosphere. Global and Planetary Change, 33, 185-203
Niewӧhner, C., Hensen, C., Kasten, S., Zabel, M., and Schulz, H. D. (1998) Deep sul-fate reduction completely mediated by anaerobic methane oxidation in sediments of the upwelling area off Namibia. Geochimica et Cosmochimica Acta, 62, 455-64.
Nagata, T. (2002) Production mechanisms of dissolved organic matter. In: Microbial Ecology of the Oceans, Ed.: Kirchman, D. L., Wiley, USA., 121-152.
Pecher, I. A. (2002) Gas hydrates on the brink. Nature, 420, 622-623.
Pop Ristova, P. (2012) Biogeochemical Activity and Associated Biodiversity at Reduced Deep-Sea Hotspot Ecosystems. PhD thesis, University Bremen.
Pop Ristova, P., Wenzhöfer, F., Ramette, A., Zabel, M., Fisher, D., Kasten, S., and Boetius, A. (2012) Bacterial diversity and biogeochemistry of different chemo-synthetic habitats of the REGAB cold seep (West African margin, 3160 m water depth). Biogeosciences , 9, 5031–5048.
Reindl, A. R. and Bolałek, J. (2014) Methane flux from sediment into near-bottom water and its variability along the Hel Peninsula—Southern Baltic Sea. Continental Shelf Research, 74, 88–93.
Ritt, B., Pierre, C., Gauthier, O., Wenzhöfer, F., Boetius. A., and Sarrazin, J. (2011) Diversity and distribution of cold-seep fauna associated with different geological and environmental settings at mud volcanoes and pockmarks of the Nile deep-sea fan. Marine Biology, 158, 1187–1210.
Rodriguez, N. M., Paull, C. K., and Borowski, W. S. (2000) Zonation of authigenic carbonates within gas hydrate-bearing sedimentary sections on the blake ridge: offshore southeastern north America1. Proceedings of the Ocean Drilling Program, Scientific Results, 164.
Sarmiento, J. L., Murnane, R., Le Quere, C., Keeling , R., and Williams, R. G.(1995) Air-sea CO2 transfer and the carbon budget of the North Atlantic. Philosophical Transactions: Biological Sciences, 348, 1324, 211-219.
Sauter, E. J., Muyakshin, S. I., Charlou, J. L, Schlüter, M., Boetius, A., Jerosch, K., Damm, E., Foucher, J. P., and Klages, M. (2006) Methane discharge from a deep-sea submarine mud volcano into the upper water column by gas hydrate-coated methane bubbles. Earth and Planetary Science Letters, 243(3-4), 354-365
Schnurle, P., Hsiuan, T. H. and Liu, C. S. (1999) Constrains on free gas and gas hydrate bearing sediments from multi-channel seismic data, offshore southwestern Taiwan. Petrologic Geological of Taiwan, 33, 21-42.
Siegenthaler, U. and Samiento, J. L. (1993) Atmospheric carbon dioxide and the ocean. Nature, 365, 119-125.
Sloan, E. D. Jr. (1998) Physical/chemical properties of gas hydrates and application to world margin stability and climatic change. In: Gas hydrates: relevance to world margin stability and climate change, In Henriet, J. P. and Mienert, J. (Eds.) Geological Society, London, Special Publications, 137, 31-50.
Sommer, S., Linke, P., Pfannkuche, O., Niemann, H., and Treude, T. (2010) Benthic respiration in a seep habitat dominated by dense beds of ampharetid polychaetes at the Hikurangi Margin (New Zealand). Marine Geology, 272, 223–232.
Stedmon, C. A., Markager, S., and Bro, R., (2003) Tracing dissolved organic matter in aquatic environments using a new approach to fluorescence spectroscopy. Marine Chemistry, 82, 239-254.
Suess, E., Torres, M. E., Bohrmann, G., Collier, R. W., Greinert, J., Linkea, P., Rehder, G., Trehu, A., Wallmann, K., Winckler, G., and Zuleger, E. (1999) Gas hydrate destabilization: enhanced dewatering, benthic material turnover and large methane plumes at the Cascadia convergent margin. Earth and Planetary Science Letters, 170, 1-15.
The Surface Ocean - Lower Atmosphere Study (SOLAS), (2003) Science Plan and Implementation Strategy, IGBP, 50, 68-69 pp.
Takahashi, T., Sutherland, S. C., Feely, R. A., Cosca, C. E. (2003) Decadal variation of the surface water pCO2 in the western and central equatorial Pacific. Sceince, 302, 852-856.
Traganza, E. D., Swinnerton, J. W., and Cheek, C. H. (1979) Methane supersaturation and ATP-zooplankton blooms in near-surface waters of the Mediterranean and the subtropical North Atlantic Ocean. Deep-Sea Res., 26, 1237-1245.
Wang, X. C., Chen, R. F., Whelan, J., and Eglinton, L. (2001) Contribution of ‘old’ carbon from natural marine hydrocarbon seeps to sedimentary and dissolved organic carbon pools in the Gulf of Mexico. Geophysical Research Letters, 28, 3313–3316.
Weiss, R. F. (1974) Carbon dioxide in water and seawater. The solubility of a non-ideal gas. Marine Chemistry, 2, 203-215.
Wiesenburg, D. A. and Guinasso, N. L. Jr. (1979) Equilibrium solubilities of methane, carbon monoxide, and hydrogen in water and sea water. Journal of chemical and Engineering Data, 24, 356-365.
Wood, W. T., Gettrust, J. F., Chapman, N. R., Spence, G. D., and Hyndman, R. D. (2002) Decreased stability of methane hydrate in marine sediments owing to phase-boundary roughness. Nature, 420, 656-660.
Yang, T. F., Chuang, P. C., Lin, S., Chen, J. C., Wang, Y., and Chung, S. H. (2006) Methane venting in gas hydrate potential area offshore of SW Taiwan: evidence of gas analysis of water column samples. Terrestrial, Atmospheric and Oceanic Sciences, 17, 933-950.
Zatsepina, O. and Buffett, B. A. (1997) Phase equilibrium of gas hydrate: Implications for the formation of hydrate in the deep-sea floor. Geophysical Research Letters, 24, 1567-1570.