Facies clustering for subterranean property modeling and well placement

A system for determining subterranean properties of a reservoir, the system comprising one or more processing devices and one or more non-transitory machine-readable storage devices storing programming instructions for execution by the one or more processing devices to cause the system to perform operations comprising:

• receiving log data for a plurality of wells in the reservoir, the log data representing at least one petrophysical property of a subsurface of the reservoir for the plurality of wells;
• generating multiple facies clusters based on the log data, each facies cluster representing a set of wells of the plurality of wells that are associated with similar values for the at least one petrophysical property of the subsurface;
• determining one or more neighbor wells for each of the plurality of wells based on geographic locations of the plurality of wells, the one or more neighbor wells being selected from the plurality of wells;
• for each of the plurality of wells, determining that the well is on a facies cluster boundary upon determining that the well and a neighbor well of the well are represented by different facies clusters;
• for each well on the facies cluster boundary:
• determining a similarity score between the well and each facies cluster, the similarity score representing a similarity between the at least one petrophysical property for the well and the at least one petrophysical property for the set of wells represented by each facies cluster;
• and
• updating the facies cluster representing the well, the updated facies cluster having the largest similarity score with the well among the multiple facies clusters;
• and
• determining the subterranean properties of the reservoir based on the multiple facies clusters and the set of wells represented by each facies cluster.

A non-transitory machine-readable storage device storing programming instructions for determining subterranean properties of a reservoir, wherein the programming instructions are for execution by at least one processing device to cause performance of operations comprising:

• receiving log data for a plurality of wells in the reservoir, the log data representing at least one petrophysical property of a subsurface of the reservoir for the plurality of wells;
• generating multiple facies clusters based on the log data, each facies cluster representing a set of wells of the plurality of wells that are associated with similar values for the at least one petrophysical property of the subsurface;
• determining one or more neighbor wells for each of the plurality of wells based on geographic locations of the plurality of wells, the one or more neighbor wells being selected from the plurality of wells;
• for each of the plurality of wells, determining that the well is on a facies cluster boundary upon determining that the well and a neighbor well of the well are represented by different facies clusters;
• for each well on the facies cluster boundary:
• determining a similarity score between the well and each facies cluster, the similarity score representing a similarity between the at least one petrophysical property for the well and the at least one petrophysical property for the set of wells represented by each facies cluster;
• and
• updating the facies cluster representing the well, the updated facies cluster having the largest similarity score with the well among the multiple facies clusters;
• and
• determining the subterranean properties of the reservoir based on the multiple facies clusters and the set of wells represented by each facies cluster.