臺灣南部嘉南地區北港溪至曾文溪間鑽井岩心之花粉分析及地層對比研究

Pollen Analysis and Correlating Strata Study in the Drilling Cores between Peikangshi and Tsengwenshi of Chiayi-Tainan Area in Southern Taiwan

曾美惠(Mei-Huei Tseng) ； 許毓純(Yu-Chwen Hsu)

《國立臺灣博物館年刊》 42卷 (1999/12) Pp. 127-150

https://doi.org/10.6548/ANTM.199912_42.0005

摘要

本研究共進行了嘉南地區十份、頂山、總爺、新塭、大崙等五口鑽井的花粉分析硏究。研究結果顯示，在各鑽井的第二帶皆爲最暖濕氣候型態，配合鑽井位置及定年資料推論，此帶應爲全新世中較溫暖的時期，年代約在距今九千至一萬年前間，各鑽井深度約在50-120公尺處不等，可藉此上下對比，其餘花粉帶可做對比的推算。其中十份、頂山和總爺鑽井的花粉帶依序對比，包括三口井的第四帶和第五帶界線，在氣候上似乎是可作對比，年代可能超過四萬年以上；頂山和總爺的第三帶和第四帶界限約在一萬三千年前左右；十份第三帶和第四帶的界線可能年代較老，約二萬六千年前左右，所以其可能對比到頂山和總爺的第四帶中期；從氣候推論，此三口井的第三帶和第五帶爲末次冰期中的小暖期，第四帶爲冷期，第一帶和第二帶皆屬於全新世暖期。以新塭和大崙鑽井而言，第五帶爲冷期，其與第四帶界線的年代無法確定，對比性較差，第三帶和第四帶氣候型態爲末次冰期中的小暖期，年代應較前述三口井（十份、頂山、總爺）的第三帶爲老，第一帶和第二帶的界限與前述鑽井相同，氣候狀況大致類似，皆屬於全新世的暖期。所以十份、頂山和總爺三口鑽井的對比情形相當好，而新溫和大崙則似乎有沉積上的間斷或不連續存在，且定年資料缺乏，增加對比上的困難。在地理位置上，前三口鑽井位於八掌溪和急水溪以南，後二口鑽井則位於以北地區，其間是否因沉積環境的相異造成兩者間的對比困難，則需配合其它地質資料才能解釋。

關鍵字

花粉分析 ； 對比 ； 嘉南地區

並列摘要

We examined five well drilling cores including Shihfen, Tingshan, Zongyeh, Hsinwen, Talun, and of the Chiayi - Tainan area in this research. The results show that the second pollen zone is the most warm -wet period in each core, about 50-120 meters in depth. We referred to the C-14 dating data to figure out the contrast of the strata from its context and correlate strata study. The drilling cores of Shihfen, Zongyeh, and Tingshan were correlated with each other depending on every sequence of the pollen zone. The boundary of the fourth/fifth pollen zone wasn't comparatively decided because there is no explicit evidence. The boundary of the third/fourth one was about 13ka, second/third one was about 10ka, and the first/second one was about 9ka. The fourth pollen zone is cool period. The third and the fifth zone are belong to the interstadial period in the last glacial age. Among them, the second zone is from the warmest period. The first and the second zones all belong to Holocene warm period. The fifth zone is the cool period in Talun and Hsinwen cores. Their third and fourth zone are from the interstadial period of the last glacial age and older than the third zone of the previous three cores (Shihfen, Zongyeh, and Tingshan). The first/second pollen zone boundary is similar to the others. They have a similar climatic condition and all belong to the warm period of the Holocene. The difficult correlation between them probably needs further study of the geography factor.

並列關鍵字

Pollen analysis ； correlation ； Chiayi - Tainan area