• 作者： 陳民本;郭欽慧
• 作者服務機構： 國立臺灣大學海洋研究所
• 中文摘要： 臺灣海峽南部8根活塞岩心中沈積物的浮游性有孔蟲可鑑定二十六種暖水性為主的浮游性有孔蟲群集。其中以Neogloboquadrina dutertrei, Globigerinoides tuber的含量為主，這兩種的含量合起來約佔所有有孔蟲的40%～60%。使用因子分析（factor analysis）和群集分析（cluster analysis）發現臺灣海峽南部的上昇流現象存在於北緯22°30′，附近，在該位置之南沒有明顯的上昇流之現象。該上昇流區域海底沈積物中之浮游性有孔蟲的冷水種含量不多，反而是以較深水性的浮游性有孔蟲Globorotalia menardii, Globorotalia tumida, Pulleniatina obliquiloculata和Globigerinoides con-globatus為主。不過，這些有孔蟲之相對含量亦顯示上昇流在此區域並非永久性的。 從水平向的浮游性有孔蟲相對含量之因子分數分佈，可發現上昇流區域沈積物中浮游性有孔蟲之分佈主要是受到南海海流的影響，黑潮反而為次要的。不過，此上昇流區域內 Globigeinoides sacculifer的含量較Globigerinoides ruber為多，顯示表層的黑潮海水在該處有轉向的趨勢。 臺灣海峽南部大陸斜坡上沈積物之浮游性有孔蟲與底棲性有孔蟲總個數之比值，顯示在東經119°30′，線上的北緯22°20′與21°50′之間海底大陸斜坡上崩移現象較離岸近的海底為強且次數頻繁。
• 英文摘要： A total of 26 species of planktonic foraminifera are identified in 8 piston cores which were collectedin the southern Taiwan Strait. These warm water assemblages may be related to those, both of the SouthChina Sea current and the Kuroshio. Mostly, the two dominant species of Neogloboqudrina dutertrei andGlobigerinoides ruber vary between 40% and 60%. Q-mode factor analysis has shown that the factor As-semblage of Globorotalia menardii, Pulleniatina obliquiloculata and Globigerinoides conglobatus is proba-bly related to the upwelling phenomenon in this area. The upwelling factor assemblage only existed in theupper 55.5cm section of core KS-4 and did not appear in the other cores. It is estimated that the upwellingassemblage was deposited in the core site of KS-4 during the last few thousand years only. Contour lines of factor 1 scores show that the South China Sea current seems to be the major con-tributor to supply the planktonic foraminifera in this upwelling region, whereas the Kuroshio only deliversthe tropical pelagic assemblages to the surface water (less than 100 meters). Globigerinoides sacculifer ismainly related to the Kuroshio. During the winter season, the Kuroshio probably changes its course to theSouth China Sea near the core site of KS-4. From the data of ratio of planktonic to benthonic foraminifera, it is reasonable to believe that theslumping and turbidity currents are frequent in the Penghu Channel located on the southern Taiwan Straitcontinental slope. The strength of the slumping activity is more active near the axis of the Channel than inthe eastern side which is closer to Taiwan.
• 中文關鍵字： planktonic foraminifera; upwelling; southern Taiwan Strait
• 英文關鍵字： --