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At the beginning of the 21st century, the 'active tectonic block model', described by hierarchical crustal tectonic blocks, was proposed to explain the distribution of continental earthquakes in China. The blocks, as well as the block boundary zones, were determined by geological, geophysical, and geodetic observations. The model, indicating that large earthquakes, especially great earthquakes, occur mainly in the boundary zones, plays an important role in seismic hazard assessment and earthquake forecast in China. The model has been tested by the seismicity in continental China in the past 20 years. Meanwhile, with new data accumulating and new technology emerging, it is possible to update the model into a new version, e.g., from 2D to 3D by considering deep structures such as crustal channel flow, and from a kinematic model to a dynamic one by computational geodynamics. The updated model could also be applied to broader continental regions for international collaborative and comparative studies. [ABSTRACT FROM AUTHOR]

Pattern informatics (PI), load/unload response ratio (LURR), state vector (SV), and accelerating moment release (AMR) are four previously unrelated subjects, which are sensitive, in varying ways, to the earthquake's source. Previous studies have indicated that the spatial extent of the stress perturbation caused by an earthquake scales with the moment of the event, allowing us to combine these methods for seismic hazard evaluation. The long-range earthquake forecasting method PI is applied to search for the seismic hotspots and identify the areas where large earthquake could be expected. And the LURR and SV methods are adopted to assess short-to-intermediate-term seismic potential in each of the critical regions derived from the PI hotspots, while the AMR method is used to provide us with asymptotic estimates of time and magnitude of the potential earthquakes. This new approach, by combining the LURR, SV and AMR methods with the choice of identified area of PI hotspots, is devised to augment current techniques for seismic hazard estimation. Using the approach, we tested the strong earthquakes occurred in Yunnan-Sichuan region, China between January 1, 2013 and December 31, 2014. We found that most of the large earthquakes, especially the earthquakes with magnitude greater than 6.0 occurred in the seismic hazard regions predicted. Similar results have been obtained in the prediction of annual earthquake tendency in Chinese mainland in 2014 and 2015. The studies evidenced that the ensemble approach could be a useful tool to detect short-to-intermediate-term precursory information of future large earthquakes. [ABSTRACT FROM AUTHOR]