車籠埔斷層深鑽岩心鏡煤素反射率研究

梁珪宏(Kuei-Hung Liang)

指導教授 ： 蔡龍珆

國立中央大學/地球科學學院/應用地質研究所/碩士(2006年)

摘要

論文提要內容：
1999年的921集集地震，車籠埔斷層給台灣地區帶來極大的生命財產損失，也引起各界對地體構造與斷層活動的重視。沈積地層中的植物殘體經深埋與成岩作用後逐漸分解重組，埋藏過程中的成岩作用、地殼變動使有機體受溫度、壓力刺激而逐漸成熟，此過程為不可逆反應，不受退化變質影響，可記錄埋藏史上最高溫的熱事件，鏡煤素反射率已被證實可反應此溫壓資料。
本研究採集車籠埔斷層豐原井、南投井及大坑井岩心內有機質，分析鏡煤素反射率，完成車籠埔斷層縱向地溫變化圖，據以瞭解斷層位置與受熱機制，進而研判斷層活動與危害潛能。實驗結果顯示鏡煤素反射率並未呈現受到斷層錯動而明顯增加的現象。可能因為車籠埔斷層並未深切地層、取樣位置不夠接近斷層、上新世及中新世地層為年輕且低溫之地層而導致。

關鍵字

鏡煤素反射率 ； 車籠埔斷層

並列摘要

ABSTRACT
The 1999. 9.21 Chi-Chi earthquake, triggered by Chelungpu Fault, led to a tremendous life and property loss in Taiwan, also aroused the attention to tectonic structures and fault activity. The plant remains in sedimentary strata gradually decompose and rearrange their organic molecules after deep burial, diagenesis, and tectonic activities. In other words, the plant macerals turn to be more matured out of the increasing temperature and pressure during thermal maturation. Furthermore, the maturation process is irreversible, not influenced by retrograde metamorphism, can only record the maximum thermal event in the burial history. Vitrinite reflectance had been proved to reflect this thermal/pressure information successfully.
The drilling work of TCDP (Taiwan Chelungpu-fault Drilling Project) core was completed on December, 2004. Core over 1500m in length was successfully recovered from –500m down to –2000m. Black carbonaceous materials were collected from this core for the purpose of evaluating thermal mechanism in the well site, especially at the fracture zones of Chelungpu Fault. The purpose of this study is to evaluate the thermal mechanism of fault zone by vitrinite reflectance. According to the study result, there is no obvious increase of vitrinite reflectance from surface to the depth of 2000m in TCDP core. It can be attributed to the reasons of 1) Chelungpu Fault did not deep-cut the strata to produce enough heat, or 2) sample positions were not close enough to the fault position.

並列關鍵字

none

參考文獻

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