One dimensional (1D) velocity models are still widely used for computing earthquake locations at seismological centers. The location accuracy of an earthquake strongly depends on the velocity model used to compute the location. In the past, the local velocity model developed for the Hangay region was lacking precision due to insufficient data. Within the framework of the “Intracontinental Deformation and Surface Uplift- Geodynamic Evolution of the Hangay Dome, Mongolia, Central Asia” project [15], 72 seismic Broadband stations network were deployed in the Hangay Dome. This gives us an opportunity to estimate the crustal velocity structure of the South Hangay region using recorded local earthquake data. For this purpose, available velocity models for the South Hangay region have been re-evaluated.  By simultaneous invertion P- and S-wave arrival times using VELEST algorithm, we estimated minimum 1D velocity models, station corrections, hypocentre locations, and origin times for the south Hangay region. Consequently, 1D crustal velocity model is proposed for the South Hangay region. This new model is expected to improve the accuracy of the routine hypocenter determination and as initial reference models for seismic tomography study.

The spatial distribution of large earthquakes in slowly deforming continental regions (SDCR) is poorly documented and, thus, has often been deemed to be random. Unlike in high strain regions, where seismic activity concentrates along major active faults, earthquakes in SDCR may seem to occur more erratically in space and time. This questions classical fault behavior models, posing paramount issues for seismic hazard assessment. Here, we investigate the M7, 1967, Mogod earthquake in Mongolia, a region recognized as a SDCR. Despite the absence of visible cumulative deformation at the ground surface, we found evidence for at least 3 surface rupturing earthquakes during the last 50,000 years, associated with a slip-rate of 0.06 ± 0.01 mm/year. These results show that in SDCR, like in faster deforming regions, deformation localizes on specific structures. However, the excessive length of return time for large earthquakes along these structures makes it more difficult to recognize earthquake series, and could conversely lead to the misconception that in SDCR earthquakes would be randomly located. Thus, our result emphasizes the need for systematic appraisal of the potential seismogenic structures in SDCR in order to lower the uncertainties associated with the seismogenic sources in seismic hazard models.

Destructive large earthquakes occur not only along major plate boundaries but also within the interior of plates. To establish appropriate safety measures, identifying intraplate active faults and the potential magnitude of associated earthquakes is essential before an earthquake occurs. This study was conducted to document the geomorphic expression of a previously unrecognized 50-km-long active fault in Ulaanbaatar, the capital of Mongolia. Mapping of the fault was accomplished using the Advanced Land Observation Satellite elevation dataset provided by Japan Aerospace Exploration Agency (JAXA), a stereo-scope interpretation of CORONA satellite images, the emplacement of trenches across the fault trace, and field study. The Ulaanbaatar fault (UBF) is marked by fault scarps on the surface and left-lateral stream deflections. The fault displaces late Pleistocene deposits and is thus considered to be active. Based on the length of the fault, the UBF is believed to be capable of causing earthquakes with magnitudes greater than M 7 and subsequent associated damage to buildings and heavy causalities within the metropolitan area. We strongly suggest that building resistance requirements in Ulaanbaatar should be revised to mitigate for the potential of extensive seismic damage. The results of this study can be used to revise the seismic hazard map and stipulate a new disaster prevention strategy to improve public safety in Ulaanbaatar. It is also possible that there may be other active faults in the vicinity of Ulaanbaatar, and these require investigation.

According to researchers, Ulaanbaatar, the capital city of Mongolia, is in an active seismic zone, and more active faults around the city have been discovered in the last few decades. This is an alarming news for the city that has been expanding and developing rapidly. Therefore, consideration of the construction of structures that can withstand strong earthquakes has been becoming a complex problem from economic perspective and urban planning. This study aims to develop response spectra for all and any structure constructs in the city. To complete this requirement, we generated maximum response spectra correlating different soil classes, and taking into considering all potential active sources around the city. In this research work, we have proposed various response spectra that are associated with five different soil classes, and these response spectra can be used for the city.

Central Asia is one of the seismically most active regions in the world. Its complex seismicity is due to the collision of the Eurasian and Indian plates, which has resulted in some of the world’s largest intra-plate events over history. The region is dominated by reverse faulting over strike slip and normal faulting events.The GSHAP project, aiming at hazard assessment on a global scale, indicates that the territory of Bayankhongor aimag, Mongolia, in Central Asia is characterized by maximum bedrock peak ground accelerations for 10% probability of exceedance in 50 years as medium as in range of 80 to 160cm/s2. In this study, which has been carried out within the framework of the project “Seismic microzoning map of center of 12 aimags, Mongolia”, the area source model and different kernel approaches are used for a probabilistic seismic hazard assessment for the Mongolia. The seismic hazard is assessed considering shallow (depth <50 km) seismicity only and employs an updated (with respect to previous projects) earthquake catalogue for the region. The hazard maps, shown in terms of 10% probability of exceedance in 50 years, are derived by using the Open Deterministic and Probabilistic Seismic Hazard Assessment (ODPSHA), which is based on the Cornell methodology. The maximum hazard observed in the region reaches 93-98 cm/s2 , which in intensity corresponds to VII in MSK64 scale in the centre of Bayankhongor aimag for 475 years mean return period.