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The characterization of a seismic source is crucial to understand seismogenic processes. Simplified source models, e.g., a moment tensor, may not be suited for certain physical processes, such as landslides or complex earthquake ruptures. We propose here a double source model to reproduce landslide processes, with two opposite oriented forces representing the detachment and impact of a sliding mass. A double source model is also suited to characterize complex earthquake ruptures, as it allows modeling the failure of two patches along a single or on two different faults. The inversion for a double source is implemented in a Bayesian bootstrap-based probabilistic inversion scheme with uncertainty estimation for all parameters. In the case of landslides, the source is described by two independent single forces and earthquakes are described by two dependent double-couples. The double single-force model includes 16 free parameters and the double double-couple model includes 18. Here we show the results obtained in the analysis of three different landslides (Val Bondasca-Switzerland 2017, Anak Krakatoa-Indonesia 2018 and Uttarakhand-India 2021) and two complex earthquake ruptures (Alaska 2018, South Sandwich islands 2021). Our findings show that our approach can resolve the landslide geometry and slope orientation. For the case of earthquakes, we were able to resolve the focal mechanism along two faults, which were active during the Alaska 2018 earthquake, as well as the time delay and orientation of the South Sandwich doublet in 2021., The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)