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Transient aseismic creep of the fault frequently induces earthquakes with high magnitude and destructiveness. In allusion to the challenges of slow sliding speed and difficult to detect, an automatic detection method of transient aseismic creep information for the fault was proposed, which based on the abnormal fluctuations of GNSS continuous coordinate time series. First, independent component analysis was used to improve the signal-to-noise ratio (SNR); then the relative strength index and kurtosis value of the fluctuations of the coordinate time series were calculated; finally a creep signal probability was converted through the cumulative distribution function, so as to the fault creep event was detected. In this paper, a 500-day GNSS surface displacement time series was simulated that included a 25-day transient creep signal. The experimental results show that the creep information of the fault can be effectively detected when the signal strength was at least equivalent to the noise level. After calculating the GNSS data for three consecutive years in the Akutan Zone, onecreep signalwas detected and it might be an aseismic creep signal related to the strong movement of the volcanic. In accordance with the processing results of seven-year GNSS data from 18 stations of the Crustal Movement Observation Network of China in Sichuan province, four abnormal signals was found. The analysis results indicated that these signals may be closely related to the abnormal displacement caused by stress accumulation and fault creep caused by the earthquake.

This paper firstly presents the basic principle of InSAR techniques in monitoring surface deformations. Then, the existing InSAR-based approaches for retrieving mining-induced 3D displacements are classified, and their technique features and application scopes are also analyzed. Subsequently, the research progress of InSAR-based 3D deformation prediction of mining areas is demonstrated. Finally, some potential research topics in retrieving and predicting mining-induced 3-D displacements using InSAR, such as integrating multi-source data and the analysis of mining subsidence mechanism, are demonstrated.

When using autonomous marine vehicles (AMVs) collecting seabed or hydrologicaldata, the algorithm of simple zigzag complete traversal path planning easily leads to repeated search regions and missed search regions in multi-bay ocean environment. This paper presents the environment expression concepts of repeated bay and missed bay with their points of entry, exit, and gateway. By modifying the simple zigzag complete traversal path planning algorithm using repeated-bay searching behavior and missed-bay searching behavior based on the those environment expression concepts, the new algorithm effectively reduces the area of the repeated search regions and the missed search regions for AMVs in complete traversal tasks. The efficiency and low energy consumption of the modified algorithms were tested for complete traversal path planning by computer simulation, which simulated an autonomous underwater vehicle (AUV) with known resistance characteristic in a gridding search area with a constant current velocity and flow distribution. Finally, the energy saving property and practicability of the modified algorithm were tested for complete traversal path planning on an unmanned surface vehicle (USV) in the lake.