Can the state of stress be determined from hydraulic fracturing data?

In 1957 Hubbert and Willis demonstrated that under favorable conditions two principal stresses can be determined from hydraulic fracturing data. More recently Scheidegger [1960, 1962], Dunlap [1963], and Kehle [1964] have determined all three principal stresses from such data. The latter authors concluded that the maximum horizontal stress is either of the same order of or in many instances appreciably greater than the overburden pressure. It can be shown, however, that the high values for the maximum horizontal stress are a consequence of the assumptions rather than of the data on which the computations are based.