A method for determining volumetric data for fluids within a geological formation having a borehole therein, the method comprising: collecting first and second dataset snapshots of the geological formation based upon measurements from the borehole at respective different first and second times, and with the borehole subject to fluid injection between the first and second times to displace fluid in the geological formation adjacent the borehole; generating a differential dataset based upon the first and second dataset snapshots; normalizing the differential dataset to generate a normalized differential dataset; determining vertices defining a geometric shape and corresponding to respective different displaced fluid signatures based upon the normalized differential dataset; determining a first line passing through a first point representing a first displaced fluid with known first properties, and directed along a corresponding first vertex; determining a second line passing through a second point representing a second displaced fluid with known second properties, and directed along a corresponding second vertex; determining an injected fluid point corresponding to the properties of the injected fluid based upon an intersection of the first line and the second line; determining another line passing through the injected fluid point, and directed along another vertex corresponding to another displaced fluid with at least one unknown property; determining a third point along the other line based upon at least one known property of the other displaced fluid; and determining a volumetric composition of the displaced fluids based upon the differential dataset, the first point, the second point, and the third point. collecting first and second dataset snapshots of the geological formation based upon measurements from the borehole at respective different first and second times, and with the borehole subject to fluid injection between the first and second times to displace fluid in the geological formation adjacent the borehole; generating a differential dataset based upon the first and second dataset snapshots; normalizing the differential dataset to generate a normalized differential dataset; determining vertices defining a geometric shape and corresponding to respective different displaced fluid signatures based upon the normalized differential dataset; determining a first line passing through a first point representing a first displaced fluid with known first properties, and directed along a corresponding first vertex; determining a second line passing through a second point representing a second displaced fluid with known second properties, and directed along a corresponding second vertex; determining an injected fluid point corresponding to the properties of the injected fluid based upon an intersection of the first line and the second line; determining another line passing through the injected fluid point, and directed along another vertex corresponding to another displaced fluid with at least one unknown property; determining a third point along the other line based upon at least one known property of the other displaced fluid; and determining a volumetric composition of the displaced fluids based upon the differential dataset, the first point, the second point, and the third point. generating a differential dataset based upon the first and second dataset snapshots; normalizing the differential dataset to generate a normalized differential dataset; determining vertices defining a geometric shape and corresponding to respective different displaced fluid signatures based upon the normalized differential dataset; determining a first line passing through a first point representing a first displaced fluid with known first properties, and directed along a corresponding first vertex; determining a second line passing through a second point representing a second displaced fluid with known second properties, and directed along a corresponding second vertex; determining an injected fluid point corresponding to the properties of the injected fluid based upon an intersection of the first line and the second line; determining another line passing through the injected fluid point, and directed along another vertex corresponding to another displaced fluid with at least one unknown property; determining a third point along the other line based upon at least one known property of the other displaced fluid; and determining a volumetric composition of the displaced fluids based upon the differential dataset, the first point, the second point, and the third point.