利用中尺度震測系統來探討二氧化碳封存場址

Investigating Geological Storage Sites of Carbon Dioxide by the Middle-scale Reflection Seismic Method

劉致育(Chih-Yu Liu)

指導教授 ： 王乾盈

國立中央大學/地球科學學院/地球物理研究所/碩士(2008年)

摘要

現今全球暖化作用越來越嚴重及顯著，對環境的衝擊也日益嚴重，大量的溫室氣體被排放。其中二氧化碳造成的影響最大，量也最多。如何減少二氧化碳則成為現今環境科學最重要的議題。有鑑於此，國際間發展了一套二氧化碳補捉與封存技術(CO2 Capture and Storage），其中地質封存是最具有潛力且最有可行性的方法之一。
本研究所使用中尺度反射震測法，來探討適合封存的場址，檢測其地下細部構造，是否為良好的地質封存區。本次首度使用震盪震源系統（MiniVibe），能量大於傳統的撞擊式震源，探勘深度大幅提升，亦維持淺層反射震測的高解析度。震盪震源是以頻率掃瞄(sweep)的方式送出震源信號，受波器接收後，經過correlation還原成波漣型震源信號，如此可以減少震源信號對環境的瞬間衝擊，增加安全性，適合都會區施測。資料處理過程也包含了各式濾波及近地表修正、速度分析、殘餘靜態修正。探勘深度達到3000m深，且震源維持相當高的解析度。
本研究區位於桃園台地，測線分佈主要是針對沿海地區探測。沿海地區工業區林立，且製造了相當大量的二氧化碳。封存場址接近排放源也可以減少運送成本。根據調查成果，桃園沿海地區地層平坦，並無構造通過，地層受到造山帶荷重影響往東南傾斜，越靠近麓山帶受到構造運動越明顯。潛在蓋層（錦水頁岩）深度約900m~1000m（厚度約140m）；儲氣層深度約1000m~1800m（厚度約800m）。縱觀四條震測剖面，此區相當具有地質封存潛力。

關鍵字

反射震測 ； 二氧化碳

並列摘要

The global warming gradually becomes a serious worldwide problem in recent years. It makes a great influence on the Earth’s environment. Due to huge quantities and heat-capacity properties, CO2 is known as the most important factor causing the global warming. How to reduce CO2 has become an urgent subject of the environmental science. The CCS (CO2 Capture and Storage）technology has been developed as a potential method to reduce CO2. It includes the capture, convey and storage of CO2. Three methods to seal up CO2 are proposed: geological sequestration, ocean sequestration and mineral carbonation. Among them, the geological sequestration is mostly feasible.
This paper reports the use of middle-scale reflection seismic method to investigate possible storage sites of CO2. We examine details of the underground structure to evaluate its potential to be a storage site. The seismic source is a ‘Minivibe’ that generates sufficiently powerful and high-frequency signals to map the structure. It is a convenient source to reduce impacts to the environment and to increase the security. The data procession procedures include different kinds of filter, near-surface correction, NMO stack, velocity analysis, and residual static correction. The penetration depth is greater than 3000m and the resolution power is within several tens of meters.
The study area is Taoyuan. The seismic lines are arranged near the coast where new industrial estates are developed and large CO2 is expected to be created that need be treated. The storage places in the same area can reduce the transportation cost. The seismic lines provide great details of the underground structural formations from the Miocene to the Pleistocene ages. All the layers are relatively flat with visible tilt angles, dipping landward. The Chinshui shale is at a depth of 1000m with the thickness about 130m that could be a good candidate as the seal rock. Below this layer, the Nanchuang formation and the Kueichulin formation are between depths of 1000~1700m, that could be good reservoir rocks. Many details including tiny faults and disturbances of structures are available to evaluate the possibility of the area to be a good CO2 storage site.

並列關鍵字

Seismic Reflection Method

參考文獻

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