採集自中國重慶芙蓉洞兩塊霰石石筍，透過210Pb和鈾系質譜定年，顯示它們的生長時間在過去6
千年內。兩塊石筍的δ13C值的變化範圍分別為0.5‰ ~ -5‰和0.5‰
~ -2‰；δ18O值的變化範圍分別為-
6.2‰ ~ -7.2‰和-7.2‰ ~ -9‰（PDB）。經過XRD的分析，這兩塊石筍是很純的霰石，沒有方解石成份
存在，而造成霰石形成的主要原因是：（1）由於芙蓉洞基岩為白雲石質石灰岩，使洞穴滲流水含有
較多的Mg2+而不利方解石形成；（2）夏季地表溫度高，白雲石/方解石的溶解比例增加；（3）生物
活動強，有利於地表下滲水中的鍶和鎂含量增加（有機質來源）；（4）洞穴頂上的包氣帶較厚，下
滲水在圍岩中運移的時間長，導致碳酸鹽在水中的飽和度高；（5）石筍與洞穴頂部距離長，CO2從水
中脫氣較多；（6）碳酸鈣沉積（或石筍生長）緩慢。雖然上述（1）-（4）項都會使得下滲水的δ
13C偏重，然而，所測量的洞穴滴水的δ13C普遍在-7 ~ -11‰，並未指示滴水的δ13C偏重。這顯示地
表的條件主要是有利於Mg2+和Sr2+在下滲溶液中的濃度增加，而使得洞穴石筍在碳酸鈣沉澱時有利於
霰石形成。由於滴水本身沒有偏重的情況，所以我們推測發生δ13C偏重的過程，是在洞穴滴水進入
洞穴後才發生的。此外，在相同沉積條件下霰石的δ13C會比方解石偏重，上述的第（5）和（6）項
以及霰石的形成，也都會造成碳酸鈣在沉澱過程中，與母液的碳同位素分餾時變重，因此使得這兩塊
石筍的δ13C（大於-5‰）比起一般石筍的δ13C偏重許多。在這種情況下，霰石石筍δ13C記錄可能難以
反映地表植被的變化。
　　對於δ18O值來說，FR0510-1頂端δ18O為-6.28‰，為現今沉積的碳酸鈣。利用洞穴滴水δ18O = -
6.76‰（SMOW）及洞穴均溫16℃，計算霰石石筍δ18O在平衡分餾狀態下為-5.92‰（PDB），與我們所
測石筍δ18O值相當接近，因此我們相信兩塊石筍樣品δ18O為平衡分餾。
　　將兩塊石筍δ18O與貴州董歌洞和湖北和尚洞石筍δ18O進行對比，發現在長時間尺度上變化一
致，短時間尺度上可能受到區域降雨影響而有差異。這兩個石筍所顯示的6000年來的δ18O記錄從老
到新持續變重到大約1000年前。這個長時間尺度的變化趨勢，指示夏季風的強度隨著太陽輻射的減弱
逐漸變弱，氣候變得乾冷。
　　在FR0510-1過去2000年的記錄中，δ18O值在1700a到850a（years ago）較重，指示包括中世紀
暖期時期在內的氣候相對乾旱；而δ18O值在800a到100a之間較輕，指示小冰期尤其是後半段時間氣
候較濕潤。芙蓉洞2000年來的石筍紀錄與和尚洞、董歌洞的紀錄基本相同，但前兩個紀錄與董歌洞的
紀錄在過去200年顯示相反的變化趨勢。這種明顯不同的變化可能顯示在短時間尺度上，各地季風降
雨在空間上的不一致性。

Two aragonite stalagmites FR0510-1 and FR0510-2 Furong Cave, Chongqing, were dated by 210Pb and 230Th/U ICPMS methods, compiling a-6000-year record of climate history under the influence of the East Asian Summer Monsoon. The δ13C of FR0510-1 ranges 0.5 ~ -5, and the δ13C of FR0510-2 ranges 0.5 ~ -2; whereas the δ18O of FR0510-1 varies from -6.2 to -7.2 (PDB) and the δ18O of FR0510-2 varies from -7.2 to -9 (PDB). By using XRD analyses, we know that these two stalagmites are aragonite formation and no calcite exist. Below are the reasons of aragonite formation:
1. Due to the bedrock of Furong Cave is dolomitic limestone, the seepage water dissolved relatively more Mg2+ which is the calcite inhibitor.
2. High surface temperature during the summer is in favor of the dissolution of dolomite than calcite.
3. High microorganism activity leads to more Sr2+ and Mg2+ contents in the seepage water from organic matters.
4. Highly supersaturated carbonate in the seepage water might be caused by the thick vadose zone and longer traveling time above the cave.
5. More CO2 degasses from drip water due to longer dripping distance from the cave ceiling to the surface of the stalagmites as they grew in a big hall in the cave.
6. Calcium carbonate precipitated slowly in the surface of stalagmites.
The reasons 1-4 above could make the δ13C of total CO2 dissolved in the seepage water becoming heavier before the CaCO3 precipitation during the stalagmite formation. However, the measured δ13C of modern dripping water ranges about -7 to -11 which do not show anomaly heavy values. Therefore, we consider that δ13C becomes heavier after the seepage water entered the cave and during the stalagmite precipitated from drip water. The factors 1-4 are the reasons of aragonite formation. Under the same conditions, carbon isotopic fractionation during CaCO3 precipitation will lead to heavier δ13C value in aragonite than that in calcite. In summary, the factors (5) and (6) as well as aragonite formation cause the δ13C of both stalagmites much heavier than δ13C of common stalagmites.
The δ18O of FR0510-1 stalagmite surface which formed in modern day is -6.28. Using the δ18O (-6.76, SMOW) of the drip water and cave temperature of 16oC, we calculate the δ18O of calcite precipitated in equilibrium fractionation, being -5.92 (PDB). This value is similar to the value of FR0510-1 surface. Therefore, we believe that the stalagmite was precipitated in oxygen isotopic equilibrium.
The compiled δ18O record of the two stalagmites compares with the Dongge Cave and Heshang Cave δ18O records, showing similar trends in long-term scale but many discrepancies in short-term scale. The increasing trend of the δ18O from 6000a(years ago) to 1000a indicates the reduced summer monsoon strength caused by decreased solar insolation from middle to late Holocene. This long-term trend illustrates that the local and regional climates became dry and cool from middle to late Holocene due to the summer monsoon weakening.
The past 2000 years record of FR0510-1 shows that the δ18O is relatively heavy from 1700a to 850a, indicating the climate was relatively dry even during Medieval Warm Period; whereas the δ18O was relatively light from 800a to 100a, reflecting relatively wet climate during the little ice age especially the late half. The past 2000 year record shows a similar trend with Heshang Cave and Dongge Cave records, Furong Cave and Heshang Cave have an opposite trend to the Dongge Cave record during the past 200 years. The opposite trends during the past 200 years may reflect spatial variations of monsoonal rain.

中文參考文獻：
王建力，袁道先，李廷勇，何瀟，李清（2008），氣候變化的岩溶紀錄，北京科學出版社。
朱學穩（1994），芙蓉洞的次生化學沉積物.中國岩溶, 13(4)，p357-368.
林柏宇（2006），利用無機沉澱溫控實驗探討碳酸鈣中穩定同位素及微量元素的分佈特性，國立成功大學地球科學所碩士論文。
李廷勇，李紅春，李俊云，袁道先，王建力，葉明陽，唐亮亮，沈川州，葉成禮（2008），重慶芙蓉洞洞穴沉積物δ13C、δ18O特徵及意義，地質論評，第54卷第5期。
李紅春，顧德隆，趙樹聲（1996），北京石花洞地區水系氫氧同位素及氚含量研究-石花洞研究系列之一，地震地質，18（4），p.325~328。
李紅春，顧德隆，陳文寄，李鐵英（1997），利用洞穴石筍的δ13C和δ18O重建3000a以來北京地區古氣候和古環境-石花洞研究系列之三，地震地質，19（1），p.77~86。
李紅春，顧德隆，陳文寄（1998），高分辨率洞穴石筍中穩定同位素應用之二：北京元大都建立後對樹林資源的破壞δ13C結果，地質評論，44 (5)，p.456-463。
劉東生，1985，黃土與環境，中國大陸科學出版社，第247-249頁
劉建宇（2004），西南師範大學碩士研究生畢業論文《基於3S技術的武隆芙蓉江黑葉猴生態環境評價》。
賴諭萱（2006），利用MC-ICP-MS及TIMS精確測量海水中鈣元素之同位素比值，國立成功大學地球科學所碩士論文。
英文參考文獻：
Cabrol P., 1978, Contribution a` l’e´tude du concre´tionnement carbonate´ des grottes du sud de la France, morphologie, gene`se et diagene`se: Centre d’Etudes et de Recherches Ge´ologiques et Hydroge´ologiques, Memoires, v. 12, Montpellier, France, 275 p.
Cabrol P., Coudray J., 1982, Climatic fluctuations influence in the genesis and diagenesis of carbonate speleothems in southwestern France: Huntsville, Alabama, National Speleological Society, Bulletin, v. 44, p. 112–117.
Coplen T. B., Winograd I. J., Landwehr J. M., Riggs A. C., 1994, 500,000-year stable carbon isotopic record from Devils Hole, Nevada, Science 21 January 1994: Vol. 263. no. 5145, pp. 361 – 365
Cosford J., Qing H. R., Eglington B., Mattey D., Yuan D. X., Zhang M. L. and Cheng H., 2008, East Asian monsoon variability since the Mid-Holocene recorded in a high-resolution, absolute-dated aragonite speleothem from eastern China, Earth and Planetary Science Letters, Volume 275, Issues 3-4, 15 November 2008, Pages 296-307
Craig H., Gordon L. L., Horibe Y., 1965, Isotope exchange effect in the evaporation of water, 1. Low temperature experimental results. Journal of Geophysical Research 68, pp. 5079–5087.
Dansgaard W., 1964, stable isotope in precipitation, Tellus, X VI (4), 436-468
Davis D. G., Palmer M. V., Palmer A. N., 1990, Extraordinary subaqueous speleothemsin Lechuguilla Cave, New Mexico: Huntsville, Alabama, National Speleological Society, Bulletin, v. 52, p. 70–86.
Denniston R. F., DuPree M., Dorale J. A., Asmeron Y., Polyak V. J., Carpenter S. J., 2007. Episodes of late Holocene aridity recorded by stalagmites from Devil's Icebox Cave, central Missouri, USA. Quaternary Research, 68: 45-52.
Dorale J. A., Edwards R. L., Gonzlez L., Ito E., 1998. Climate and vegetation history of the midcontinent from 75 to 25 ka: A speleothem record from Crevice Cave, Missouri, USA. Science, 282: 1871-1874.
Dykoski C. A., Edwards R. L., Cheng H., Yuan D. X., Cai Y. J., Zhang M. L., Lin Y. S., Qing J. M., An Z. S., Revenaugh J., 2005, A high-resolution, absolute - dated Holocene and deglacial Asian monsoon record from Dongge Cave, China. Earth and Planetary Science Letters, Volume 233, Issues 1-2, 30, Pages 71-86.Epstein S., Mayeda T., 1953, Variation of 18O content of waters from natural sources. Geochimica et Cosmochimica Acta, v. 4, n. 5, 213-224.
Emerich K., Ehhalt D. H., Vogel J. C., 1970, Carbon isotope fractionation during the precipitation of calcium carbonate. Earth Planet. Sci. Lett. a,-363137 I.
Emiliani C., 1955, Pleistocene temperature, Journal of Geology, 63, 538-578
Epstein S., Buchsbaum R., Lowenstam H.A., Urey H.C., 1953, Revised carbonate-water isotopic temperature scale. Geological Society of America Bulletin, v. 64, 1315-1326.
Fairbridge, R. W., 1972, Climatology of a glacial cycle, Quaternary Research, 2(3), 238-302Fairchild I. J., Smith C. L., Baker A., Fuller L., Spotl C., Mattey D., McDermott F., 2006, Modification and preservation of environmental signals in speleothems. Earth Science Reviews . ISSN 0012-8252
Fairchild I. J., Smith C. L., Baker A., Fuller L., Sptl C., Mattey D., McDermott F., E.I.M.F, 2006, Modification and preservation of environmental signals in speleothems. Earth-Science Reviews, 75: 105-153.
Finch A. A., Shaw P. A., Weedon G. P., Holmgren K., 2001, Trace element variation in speleothem aragonite: potential for palaeoenvironmental reconstruction, Earth and Planetary Science Letters, Volume 186, Issue 2, 30 March 2001, Pages 255-267
Fleitmann D., Burns S. J., Manginic A., Mudelseed M., Kramersa J., Villaa I., Neff U., Al-Subbarye A. A., Buettner A., Hipplera D., Matter A., 2007, Holocene ITCZ and Indian monsoon dynamics recorded in stalagmites from Oman and Yemen (Socotra). Quaternary Science Reviews, 26: 170-188.
Frisia S., Borsato A, Fairchild I. J., McDermott F., Selmo E. M., 2002, Aragonite-Calcite relationships in speleothems (Grotte De Clamouse, France): Environmental, Fabrics. and Carbonate geochemistry, Journal of Sedimentary Research; v. 72; no. 5; p. 687-699
GRIP members, 1993, Climate instability during the last interglacial period recorded in the CRIP ice core, Nature,364, 203-207
Grossman E. L., Ku T. L., 1986, Oxygen and carbon isotope fractionation in biogenic aragonite: Temperature effects. Chem. Geol. 59, 59-74.
Harmon, R.S., Atkinson, T.C., Atkinson, J.L., 1983, The mineralogy of Castleguard Cave, Columbia Icefields, Alberta Canada: Arctic and Alpine Research, v. 15, p. 503–516.
Helgeson H. C., Delany J. M., Nesbitt H. W., Byrd D. K., 1978, Summary and critique of the thermodynamic properties of rock-forming minerals: American Journal of Science, v.278A, p. 1–229.
Hellstrom J., Mcculloch M., Stone J., 1998. A detailed 31,000-year record of climate and vegetation change, from the isotope geochemistry of two New Zealand speleothems. Quaternary Research, 50: 167-178.
Hendy C. H., 1969, The isotope geochemistry of speleothems and its application to the study of past climates. Geochimica et Cosmochimica Acta, vol. 35, Issue 8, pp.801-824
Hill C.A., 1999, Mineralogy of Kartchner Caverns, Arizona: Journal of Cave and Karst Studies, v. 61, p. 73–78.
Hu C. Y., Henderson G. M., Huang J. H., Xie S. C., Sun Y., Johnson K. R., 2008, Quantification of Holocene Asian monsoon rainfall from spatially separated cave records, Earth and Planetary Science Letters 266 (2008) 221–232
Huang Y., Fairchild I. J., Borsato A., Frisia S., Cassidy N. J., McDermott F., Hawkesworth, C. J., 2001, Seasonal variations in Sr, Mg and P in modern speleothems (Grotta di Ernesto, Italy). Chemical Geology, 175, 429-448.
Lauritzen S. E., 1995, High-Resolution Paleotemperature Proxy Record for the Last Interglaciation Based on Norwegian Speleothems, Quaternary Research, Volume 43, Issue 2, March 1995, Pages 133-146
Li H. C., Ku T. L., You C. F., Cheng H., Edwards R. L., Ma Z. B., Tsai W. S., Li M. D., 2005, 87Sr/86Sr and Sr/Ca in speleothems for paleoclimate reconstruction in Central China between 70 and 280 kyr ago. Geochimica et Cosmochimica Acta 69: 3933-3947.
McCrea J. M., 1950, On the isotopic chemistry of carbonates and a paleotemperature scale. J. Chem. Phys. 18, 849-853.
O'Neil J. R., Epstein S., 1966, Oxygen isotope fractionation in the system dolomite-calcite-carbon dioxide. Science, 152, 198-201.
O'Neil J. R., Clayton R. N., 1964, Oxygen isotope geothermometry. In isotopic and cosmic chemistry (eds.Craig, H. Miller, S.L. and Wasserburg, G.J.), North-Holland, Amsterdam, 157-168.
O'Neil J. R., Clayton R. N., and Mayeda T. K., 1969, Oxygen isotope fractionation in divalent metal carbonates. J. Chem. Phys. 51, 5547-5558.
O'Neil J. R., 1986, Theoretical and experimental aspects of isotopic fractionation. In Stable Isotopes in High Temperature Geological Processes (ed. J. W. Valley et al.); Rev. Mineral. 16, 1-40.
O'Neil J. R., Barnes I., 1971, C-13 and O-18 compositions in some fresh-water carbonates associated with ultramafic rocks and serpentinites, western United States. Geochim. Cosmochim. Aeta 35, 687-697.
O'Neil J. R., Truesdell A. H., 1991, Oxygen isotope fractionation studies of solute-water interactions. In Stable Isotope Geochemistry: A Tribute to Samuel Epstein (ed. H. P. Taylor, Jr. et al.); Geochem. Soe. Spec. Publ. 3, 17-25.
O'Neil J. R., Adami L., and Epstein S., 1975, Revised value for the O 18 fractionation between CO2 and H20 at 25°C. J. Res. US Geol. Surv. 3, 623-624.
Roberts M. S., Smart P. L., Baker A., 1998, Annual trace element variations in a Holocene speleothem. Earth and Planetary Science Letters, 154, p237-246。
Romanek C. S., Grossman E. L., Morse J. W., 1992, Carbon isotopic fractionation in synthetic aragonite and calcite: Effects of temperature and precipitation rate, Geochimica et Cosmochimica Acta Vol. 56, pp. 419-430
Rozanski K., Aragus-Aragus L. and Gonfiantini R., 1993. Isotopic patterns in modern global precipitation. In: P.K. Swart, K.C. Lohmann, J. McKenzie and S. Savin (Eds), Climate Change in Continental Isotopic Records. Geophysical Monograph 78, American Geophysical Union, Washington, D.C, pp.1-36.
Rubinson M., Clayton R. N., 1969, Carbon-13 fractionation between aragonite and calcite，Geochimica et Cosmochimica Acta, Volume 33, Issue 8, Pages 997-1002.
Sunagawa I., 1984, Growth of crystals in nature, in Sunagawa, I., ed., Material Science of　the Earth’s Interior: Tokyo, Tokyo Scientific Publishing Company, p. 63–105.
Turin, H.J., Plummer, M.A., 2000, Lechuguilla cave pool chemistry, 1986–1999: Journal of Cave and Karst Studies, v. 62, p. 135–143.
Turnbull A.G., 1973. A thermochemical study of vaterite. Geochim. Cosmochim. Acta 37, pp. 1593–1601.
Turner J. V., 1982, Kinetic fractionation of carbon-13 during calcium carbonate precipitation. Geochim. Cosmochim. Acta 46, 1183-1191.
Urey H. C. (1947) The thermodynamic properties of isotopic substance, J. Chem. Soc. (London) 562-581
Wang Y. J., Cheng H., Edwards R. L., An Z. S., Wu J. Y., Shen C. C., Dorale J. A., 2001. A High-resolution absolute-dated late Pleistocene monsoon record from Hulu Cave, China. Science, 294: 2345-2348.
Wang Y. J., Cheng H., Edwards R. L., He Y. Q., Kong X. G., Zn Z. S., Wu J. Y., Kelly M. J., Dykoski C. A., Li X. D., 2005. The Holocene Asian monsoon: Links to solar changes and North Atlantic climate. Science, 308: 854-857.
Wang Y. J., Cheng H., Edwards R. L., Kong X. G., Shao X. H., Chen S. T., Wu J. Y., Jiang X. Y., Wang X. F., An Z. S., 2008. Millennial- and orbital-scale changes in the east Asia monsoon over the past 224000 years. Nature, 451: 1090-1093.
Yuan D. X., Cheng H., Edwards R. L., Dykoski C. A., Kelly M. J., Zhang M. L., Qing J. M., Lin Y. S., Wang Y. J., Wu J. Y., Dorale J. A., An Z. S., Cai Y. J., 2004. Timing, duration, and transitions of the last interglacial Asian monsoon. Science, 203: 575-578.
Zhang P. Z., Cheng H., Edwards R. L., Chen F. H., Wang Y. J., Yang X. L, Liu J., Tan M., Wang X. F., Liu J. H., An C. L., Dai Z. B., Zhou J., Zhang D. Z., Jia J. H., Jin L. Y., Johnson K. R., 2008, A test of climate, sun, and culture relationships from an 1810-Year Chinese cave record, Science 322, 940