This is the first comprehensive study for a seismic macro-zonation of the National Capital Region of India by using the probabilistic seismic hazard analysis approach. A modified gridded seismicity model is used for this purpose, in which the earthquake occurrence rates obtained using the Gutenberg-Richter's (G-R) relationships for conventional area type seismic sources are distributed non-uniformly among a grid of cells. This provides a more robust approach than the commonly used weighted sum of area sources of homogeneous seismicity and the zone-free smoothed gridded seismicity. Other distinguishing features of the present analysis include: detailed seismotectonic evaluation of the region to identify seven area type seismic sources, compilation of a comprehensive earthquake catalogue for the estimation of seismicity recurrence parameters, selection of the most appropriate ground motion prediction equation by using a database of 71 strong motion accelerograms recorded in the region, and estimation of the compatible distance parameters by associating a fictitious fault rupture plane to each grid cell with appropriate strike and dip angles. Hazards maps are prepared for the hard rock site condition in terms of the peak ground acceleration and the 5%-damping acceleration response spectrum amplitudes for several combinations of natural periods and return periods. A simple empirical approach is also developed to obtain amplification factors for modifying the uniform hazard response spectra for the rock sites to those for the soil sites with a given $V_{S30}$ value. The hazard estimates from this study are found to be somewhat higher with greater site-to-site variations as compared to those from the earlier studies.

这是首次使用概率地震危险性分析方法对印度国家首都辖区地震宏观分区进行的综合研究。为此，使用了改进的网格化地震活动模型，其中使用常规区域类型地震源的古腾堡-里希特（GR）关系获得的地震发生率不均匀地分布在单元格中。与同质地震活动性和无区域平滑网格化地震活动性的常用加权总和相比，这提供了一种更可靠的方法。本分析的其他显着特征包括：对该地区进行详细的地震构造评估，以识别七个区域类型的地震源；编制综合的地震目录以估算地震活动复发参数；通过使用记录在该区域中的71个强运动加速度图的数据库，选择最合适的地面运动预测方程，并通过将虚拟断层破裂平面与每个网格单元关联的合适的走向和倾角来估计兼容的距离参数。根据自然周期和返回周期的几种组合，根据峰值地面加速度和5％阻尼加速度响应谱振幅为硬岩场地条件准备了危害图。还开发了一种简单的经验方法来获得放大因子，以将岩石场所的均匀危害响应谱修改为给定条件下的土壤站点的均匀危害响应谱。${\mathrm{伏特}}_{\mathrm{小号}30}$价值。与早期研究相比，发现该研究的危险估计值在较高的站点间差异中要更高一些。