台灣弧-陸碰撞造山帶的形成是極具挑戰性的科學問題，「薄皮理論」及「岩石圈碰撞」都曾經用來解釋台灣造山帶所觀測到的資料。Suppe (1987)首先提出台灣的薄皮構造模型，認為板塊隱沒發生在厚15 公里增積岩體內。不過，隨著台灣地震數據的增加，有證據顯示在中央山脈下的地殼有50 公里厚，並發現速度分佈不符合增積岩體模型，Wu（1996）提出岩石圈增厚模型來解釋此現象。本計畫承襲TAIGER 計畫（2007～2009 年），探討現有的造山帶模型，實驗的設計達到以前沒辦法獲得的地殼與地函構造的測繪精度。TAIGER 計畫完成大量野外工作，現在正積極整理資料，初步發現台灣莫荷面深度南北變化都在35～45km 範圍，且北深南薄。 2010～2012 年，中國福建省地震局在福建省內施放一連串的炸藥震源（1000~3000kg），沿著原來TAIGER 測線的方向施放，本計畫把握此良機，規劃跨越台灣海峽震測計畫（ATSEE），發動國內學界，布置海陸測線，接收此難得的高爆信號，以完成橫跨台灣－台灣海峽－福建之剖面，探討從台灣造山帶到大陸穩定地塊的構造變化。2010 年已完成南線4 個炮點，發現南台灣底下有明顯山根（莫荷面深度不超過40 公里）。2011 年將進行北線（福州-新竹-宜蘭）的炸測工作。 The Taiwan arc-continent collision is one of the most challenged tectonic problems in the world. Both ‘thin-skinned model’ and ‘lithospheric collision model’ have been invoked to explain the geologic and geophysical observations. The thin-skinned tectonics model was proposed by Suppe (1987), which calls for the buildup of a 15-km thick wedge during subduction of the Asian lithosphere. With the improved Taiwan seismic network in 1991, the local earthquake data became adequate for more detailed seismic tomography. The imaged crust under the Central Range can be as deep as 50 km and the general velocity structures under the Central Range are found inconsistent with those of an accretionary wedge. Wu et al. (1997) considered all these data and proposed that a continuous lithospheric deformation model (Molnar et al., 1999), which predicts the deformation extending not only into the lower crust but also into the upper mantle. The integrated research plan TAIGER has been carried out during 2007~2009, including: 1) passive earthquake source broadband seismometer observation, 2) land thousand-kg dynamite explosion, 3) sea-land airgun shooting, 4) MT profile, 5) rock property analysis and dating, 6) theoretical plate collision modeling. At the present time, the data processing is actively undertaken. The preliminary results show that the Moho is deeper in the north (> 40km) than in the south. The thin-skin model could be appropriate for the middle and south Taiwan, but the lithosphere collision model may prevail in the north. The present proposal is an extension of the 2008 experiment. At 2009, the Fujan earthquake bureau created a long-term project making a sequence of big explosions (1000~3000kg) to detect crust structures. To catch the explosion signals, we organize the ‘Across Taiwan Strait Explosion Experiment (ATSEE)’ to deploy sea-land instruments to receive these precious signals from the mainland. In ATSEE2010 project, we found very important Pn signals from the Moho directly under the Central-mountain range. The Moho depth is less than 38 km. In this year (ATSEE2011) , we will plan the line along the TAIGER’s N-line. The OBS’s will be deployed in both Taiwan-Strait and the eastern Taiwan offshore to cover a wider Pn range. Two lines on the Taiwan island are also scheduled to measure the structure in the northern Taiwan. 研究期間：10008 ~ 10107
