2010-08-012024-05-18https://scholars.lib.ntu.edu.tw/handle/123456789/709789摘要：本計畫是整合計畫：台灣―菲律賓地體動力學研究-II的子計畫之一。主要目標是針對菲律賓Taal火山進行研究，利用記錄在湖泊岩芯的地球化學資訊反演火山活動事件以及對周圍沉積環境的影響，為研究該地區晚更新世以來的構造活動、氣候變化、沉積環境提供資訊，對研究整個臺灣-菲律賓地體動力學的機制做出貢獻。經過前三年的研究，我們已經掌握了菲律賓中部塔奧火山湖的地球化學特徵，對各系統的穩定同位素組成進行了詳細地調查，並找出了一些反映火山活動的一些指示性元素和同位素特徵。在2008年11月，從塔奧火山湖的西岸鑽取了一根65米長的岩芯，鑽探深度達84米，總取心率為70%。這是塔奧火山湖地區的第一根岩芯，能夠呈現連續完整的晚更新世以來的沉積歷史以及火山噴發記錄。目前已經做好切割、照相整理、深度記錄和岩性描述，每隔5公分採集了樣品。98年度主要任務是對岩芯進行碳十四定年和样品物理性质分析。在99年度計畫中，將對1400個采自岩芯的標本進行初步的化學分析，取得TOC，TIC，稀酸可溶相的常量與微量元素含量。根據結果，分出湖泊沉積和火山堆積，釐清這些參數變化的原因，闡述湖泊在氣候、火山活動及其它構造事件影響下的變化，為解釋該區的地體動力機制積累證據。<br> Abstract: This is a subproposal of an integrated project named Taiwan-Philippine Geodynamic Study — Phase II. The research goal of this subproposal aims to understand sedimentary history of Taal Lake and volcanic eruption events of Taal volcano since late Pleistocene via geochemical proxies retrieved from a 65-m long core. During the past three years, we have studied the geochemical and isotopic features of Taal Volcano system including Taal Lake and its tributaries, geothermal inputs, vegetations, and sediments of the past 100 years. We have found several indicators of geothermal activities, such as acid-leachable Fe, Mn, Cu, Zn and K, as well as isotopic values for hydrological balance. These results will help us in understanding of geochemical behavior in the sedimentary history of the lake. In November 2008, we drilled a 65-m long core on the western shore of Taal Lake. The total drilling depth is 84 m, with a coring recovery yield about 70%. Although the drilling was not perfect, this long core is the first drilling in the region. It reveals a continuously depositional history of Taal Lake sediments which recorded volcanic eruption events, changes in paleoclimate, vegetation, ecological status and tectonic movements of the Taal Volcanic area. This long core has been cut, logged, photographed and described in its stratigraphy. We have subsampled 1400 samples at the interval of 5 cm from the core. Currently, in the 2009-2010 year project we are dating this core by using AMS radiocarbon in the KECK radiocarbon Lab at UC Irvine, and conducting physical analyses of the core materials. In the 2010-2011 year project, we will carry out analyses of TOC, TIC, acid-leachable major/minor and trace elements in the 1400 samples. We will identify lake sediments and volcanic deposits in the core, describe the geochemical features of the core, and explain the causes and meanings of the parameters. The conclusions to be drawn will contribute to our understanding of the Taal Lake and Volcano history and to the geodynamics of Taiwan-Philippine block as a whole.Taal火山湖泊沉積岩芯地球化學火山活動古氣候和古環境Taal VolcanoLake sediment coreGeochemistryVolcanic activityPaleoclimate and paleoenvironment台灣與菲律賓地體動力學研究-II-重建記錄在一個65米長岩芯中的塔奧火山湖沉積歷史及火山活動事件(I)