台灣位於歐亞板塊與菲律賓海板塊的碰撞帶，地震活動頻繁，對於研究造山過程具有重要價值。觀測這幾年來的地震目錄的地震分布後發現在雪山區域存在無震帶。
這項研究旨在利用地震和重力資料的聯合反演來探究台灣雪山地區的速度構造。利用中央氣象署的長期觀測資料以及國立中央大學臨時地震站所獲得的資料，來探究雪山地區的速度構造。考慮到地震波在淺層的解析度有限，應用了重力資料為淺層模型提供較好的控制。通過結合重力和速度逆推，得到了研究區域的速度和密度模型。
結果顯示重力改變區域在20公里內且在此深度內的速度逆推中具有良好的解析度。對台灣雪山山脈的地殼構造進行了詳細分析。結果顯示，重力逆推顯著提高了地殼構造模型的解析度，尤其在西部麓山帶、中央山脈和雪山山脈區域。此外，速度模型顯示不同深度的地殼速度特徵和與重力資料一致的地質構造，並與前人研究結果進行對比，揭示了模型解析度和精度的提升。這些研究成果對理解區域地殼構造提供了重要的地球物理學參考。
本研究展示了雙差分層析法和重力逆推方法在地震與重力資料整合中的有效性，能夠建立出更準確的地下模型，深化了對雪山地區地質構造的認識。這些結果對於理解臺灣的地質構造和地震活動分佈特徵具有重要意義，並為後續的地質和地球物理研究提供了有價值的參考資料。 

Taiwan is located at the collision zone between the Eurasian Plate and the Philippine Sea Plate, making it active and valuable for studying orogenic processes. Observing the earthquake distribution over recent years reveals a seismic gap in the Hsuehshan area. This study aims to explore the velocity structure of the Hsuehshan area in Taiwan using joint inversion of seismic and gravity data. Observation data from the Central Weather Administration and temporary seismic station data from National Central University are utilized to investigate the velocity structure of the Hsuehshan area. Considering the limited resolution of seismic waves in shallow layers, gravity data is applied to control the shallow model. By combining gravity and velocity inversion algorithms, velocity and density models of the study area are obtained.
Results show that the gravity anomaly region changes within 20 km and that the velocity inversion within this depth has good resolution. Through gravity inversion and velocity model reconstruction, a detailed analysis of the crustal structure of the Hsuehshan Range in Taiwan is conducted. The results indicate that gravity inversion significantly improves the resolution of the crustal structure model. Additionally, the velocity model shows different depth crustal velocity characteristics and geological information consistent with gravity data. Comparing these results with previous studies reveals an enhancement in model resolution and accuracy. These findings provide important geophysical insights into the regional crustal structure.
This study demonstrates the effectiveness of the double-difference tomography and gravity inversion methods in integrating seismic and gravity data, enabling the creation of more accurate subsurface models. It deepens the understanding of the geological structure of the Hsuehshan area. These results are significant for understanding the structure and earthquake distribution in Taiwan, offering reference data for future geological and geophysical research.

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