台灣西部油氣蘊藏之地化研究－苗栗外海地區

Geochemical Study of Hydrocarbon Resources in Western Taiwan-Miaoli Offshore Area

郭政隆(Cheng-Lung Kuo) ； 吳素慧(Suh-Huey Wu) ； 周次雄(Tzu-Hsiung Chou) ； 邱仲信(Jong-Hsin Chiu) ； 林宏仁(Hong-Jen Lin) ； 林麗華(Li-Hua Lin)

《鑛冶：中國鑛冶工程學會會刊》 42卷1期 (1998/03) Pp. 61-72

https://doi.org/10.30069/MM.199803_42(1).0006

摘要

本文分析研究苗栗外海生油岩潛能、生油岩厚度及有機物生成油氣轉化率，以作為估算該地區油氣蘊藏量的參考。同時從飽和烴分佈、生物指標指紋及碳同位素分析，探討該地區油樣特性及來源，結果如下：苗栗外海木山層及五指山層有頗多煤及煤頁岩分佈，這些煤及煤頁岩是良好的產氣帶凝結油之生油岩。木山層及鑽遇的五指山層良好級生油岩（TOC＞1%或S_2＞ 1 mgHC/gRock）約佔其厚度15-20%，有機物成熟度0.5-1.0%Ro，油氣轉化率5-30%。E-2號井北寮砂岩原油為成熟中期陸相有機物的產物，生物指標與碳同位素分析結果顯示與W-1號井五指山層岩樣萃取物較接近，只是原油相對含較多量陸源有機物。E-2號井木山層重油為成熟早期陸相氧化環境有機物的產物，具有煤系有機物及雙鞭毛藻的特徵，從該重油地化特性判斷應為近距離移棲。

關鍵字

地化 ； 台灣 ； 苗栗外海

並列摘要

This paper deals with the hydrocarbon generation potential, source rock thickness and organic matter-to-hydrocarbon transformation ratio in Miaoli offshore area. The result is to be used as a reference to estimate the hydrocarbon reserves of this area. Simultaneously, the hydrocarbon characteristic and source input have been studied from the saturate gas-chromatogram distribution, biomarker fingerprint and carbon isotope analysis. The results are as follows: In Miaoli offshore, the source rock of Mushan Formation and Wuhchishan Formation contains abundant coal and coaly shale which is good source of gas with condensate. The high grade source rock (TOC＞1% or S2 ＞ 1mg HC/g Rock) in Mushan Format ion and drilled Wuhchishan Formation occupy about 15-20% of the thickness. Those source rocks have 0.5-1.0% Ro maturity level and 5-30% hydrocarbon transformation ratio. There are two type oils having been discovered in E-2 well, i.e. crude oil from Peiliao Sandstone and heavy oil from Mushan Formation. The crude oil is derived from middle mature organic matter which is deposited in terrestrial environment. The biomarker fingerprint and carbon isotope dating of the crude oil are similar to that of the source rock extract of W-1 well 'in Wuhchishan Formation. The crude oil contains more terrestrial organic source input than the source rock extract of W-1 in Wuhchishan Formation. The heavy oil is derived from early mature organic matter which is deposited in terrestrial and oxidization environment, Geochemical characteristic of the heavy oil shows that it is formed with short distance migration and contain coal and Dinoflagellate compound.

並列關鍵字

Geochemical ； Taiwan ； Miaoli offshore