Methods of generating a parameter realization for a subsurface parameter

A method of generating a parameter realization, for a subsurface parameter, as a function of depth within a subsurface region, the method comprising:

• measuring, during drilling of a wellbore within the subsurface region, one or more values associated with the subsurface region to obtain one or more measured values;
• determining, based on the one or more measured values, a subsurface parameter profile for the subsurface region;
• dividing the subsurface parameter profile for the subsurface region into a plurality of adjacent stratigraphic units, wherein the subsurface parameter profile includes a probability distribution of the subsurface parameter as a function of depth within the subsurface region, and further wherein each stratigraphic unit of the plurality of adjacent stratigraphic units extends within a corresponding stratigraphic depth range within the subsurface region;
• splitting each stratigraphic unit into a plurality of stratigraphic unit layers, wherein each stratigraphic unit layer of the plurality of stratigraphic unit layers extends within a corresponding layer depth range that is a subset of the corresponding stratigraphic depth range for each stratigraphic unit;
• within each stratigraphic unit layer of the plurality of stratigraphic unit layers of each stratigraphic unit and based, at least in part, on the subsurface parameter profile within each stratigraphic unit layer, determining a layer parameter value range that extends between a layer minimum parameter value and a layer maximum parameter value;
• within each stratigraphic unit layer, selecting a corresponding layer parameter value from within the layer parameter value range;
• generating the parameter realization by assigning the corresponding layer parameter value to the parameter realization for the corresponding layer depth range of each stratigraphic unit layer;
• and
• utilizing the parameter realization as an input to a model of the subsurface region.