Upgrade to the continuous GPS network on Sierra Negra volcano, Galapagos

该项目的主要目标是在加拉帕戈斯伊萨贝拉岛Sierra Negra火山现有的8个连续全球定位系统（CGPS）站的基础上增加两个CGPS站。 该网络最初于2002年6月安装，成功地捕捉到了2005年10月Sierra Negra火山爆发前和爆发期间的异常变形。 在喷发之前有多个？活板门断层火山口底部的事件，以及30个月内上升2.2米的加速膨胀（？活板门断层是弯曲的断层，将隆起的块体与一侧的铰链区结合在一起，就像活板门一样）。 更多的活板门断层，堤防入侵，并在破火山口超过5米的沉降与喷发本身。这两个新增的CGPS站将使调查人员能够填补变形监测方面的一个关键空白，将消除卫星雷达干涉测量（干涉合成孔径雷达）场景中的模糊性，这种场景在断层系统中是不连续的，并将有助于更好地探测火山正在发生的变形并建立模型。 这项工作是及时的，因为Sierra Negra在2005年10月火山爆发结束后立即开始重新膨胀，火山口中心已经上升了2米多。 按照这种膨胀速度，未来几年可能会有更多的活板门断层事件或火山爆发。 该项目将确保研究人员从这座非常活跃的火山的未来事件中尽可能多地了解情况，这是地球上研究岩浆在空间和时间上的浅层侵入的最佳地点之一。

The main objective of this project is to add two additional continuous Global Positioning System (CGPS) stations to the existing 8-station CGPS network at Sierra Negra volcano, on the Galapagos island of Isabela. This network, originally installed in June 2002, successfully captured the extraordinary deformation leading up to and during the October 2005 eruption at the Sierra Negra. The eruption was preceded by multiple ?trapdoor faulting? events in the caldera floor, and accelerating inflation that amounted to 2.2 m of uplift in 30 months (?trapdoor faults? are curved faults that bound an uplifted block with a hinge zone on one side, like a trapdoor). More trapdoor faulting, dike intrusion, and subsidence of over 5 m in the caldera were associated with the eruption itself. The two additional CGPS stations will allow the investigators to fill a critical gap in the deformation monitoring, will eliminate ambiguity in satellite radar interferometry (InSAR) scenes that are discontinuous across the fault system, and will help better detection and modeling of the on-going deformation at the volcano. This work is timely because Sierra Negra began to re-inflate as soon as the October 2005 eruption was over and the center of the caldera has already been uplifted by over 2 m. At this rate of inflation, more trapdoor faulting events or eruptions are likely within the next few years. This project will ensure that researchers learn as much as possible from future events at this very active volcano, which is one of the best places on Earth to study the shallow intrusion of magma in space and time.