研究期間：10108~10207;The island of Mindoro locates on the southernmost tip of the Taiwan-Manila trench system. Some geological features here resemble those of the northernmost tip in Taiwan, e.g., the termination of trench and Wadati-Benioff zone as we traced into the interior of the island, and the high mountain range in the central part of the island. It is interesting to raise the following similar questions in Mindoro. (1) How and where the transition from subduction to collision occurs? (2) What are the slab stress patterns? (3) The lacking of the Wadati-Benioff zone beneath central Mindoro is due to the absence of slab or the presence of an aseismic slab? To tackle the aforementioned questions, we have deployed a seismic network of ten short-period stations centered around NW Mindoro in previous projects. In the proposal, we show preliminary results of processing collected one-year data and compare with those of PHIVOLCS catalogue. The results reveal that Mindoro is indeed a high seismic region worthwhile deployment of a high dense array with excellent instruments. We thus propose to deploy five additional broadband stations in the region in this project, taking advantage of our experience of the short-period network deployment. The addition of high quality broadband data together with short-period data will contribute significantly better in earthquake location and slab feature delineation. Furthermore, data of teleseismic events recorded by the broadband stations can be used to study the upper mantle structures beneath Mindoro, similar to what we did in Taiwan.