Method of seismic inversion using artificial kinematic constraints

A computer implemented method for extracting or estimating velocity and density from seismic traces acquired from a subsurface formation comprising the following steps:

• preparing an initial model with initial functions of velocity and density taken as constants or measured by obtaining seismic trace(s) by representing reflected seismic wavefields or measured by obtaining borehole logs;
• generating synthetic trace(s) from the initial functions of velocity and density function(s) by forward modeling seismic wave propagation through the subsurface formation with added artificial kinematic constraints and randomly updating the initial functions of velocity and density in random start and length time or depth window(s);
• creating updated synthetic traces, using randomly updated the velocity and density functions, wherein for each iteration, artificial wave(s) traveling from a source point to a reflection point and back to any receiver are simulated as a constraint to reproduce travel-time and moveout behavior of seismic events;
• performing a search of a misfit object function of any norm between original or real trace or traces and the synthetic trace(s) generated in the following iteration based on comparison of amplitude and temporal alignment of seismic reflections;
• using probabilistic techniques for approximating the global optimum;
• and
• minimizing the cost function associated with the seismic trace(s) mismatch to generate a subsurface model of the formation including spatially varying velocity and density.