SUMMARY

Forecasting earthquake with M ³ 5,0 in the Tuần Giáo and adjacent areas
by the application of CORA-3 algorithm

Nguyễn Hữu Tuyên, Chu Văn Ngợi, Cao Đình Triều

Seismogenic nodes capable of causing earthquakes with M ³ 5.0 have been determined in the Tuần Giáo area in West Bắc Bộ that exhibit the highest seismic activity over the Vietnamese territory. Forecasted objects, morphostructural nodes, have been delineated with the Geodynamics Block Model (GBM) and their classification into seismogenic and non-seismogenic nodes was performed with the pattern-recognition.

With GBM we have compiled a Geodynamic block map (at 1: 200,000 scale) for the study region. The map shows the hierarchical block-structure of the area, the network of boundary zones bounding blocks, and the locations of the nodes. A three-level hierarchy has been established for the blocks and their boundaries. The recorded M ³ 5,0 earthquakes concentrate at the nodes delineated by GBM, i.e. ignoring the seismic record. Among all delineated nodes we recognized the seismogenic ones (D), prone to nd M ³ 5,0 earthquakes, with the identification algorithm CORA-3. The performed recognition pin-points a number of D nodes where earthquakes with M ³ 5,0 have not been recorded up to date. Almost the potential of forecasted seismogenic nodes occurs along the boundaries of the 2^nd rank of geodynamic blocks.

Người biên tập: TS. Lê Tử Sơn.