A thoron field is a field comprised of thoron particles. One can use a thoron field to distort and jam the sensor readings of threat forces.

In a confrontation with two Cardassian warships shortly after the discovery of the wormhole, Major Kira Nerys at starbase Deep Space 9 used a combination of thoron fields and duranium shadows to give the appearance that the space station was bristling with armaments. (DS9: "Emissary")

In 2369 Miles O'Brien launched a class 4 probe into a subspace anomaly. The probe penetrated the thoron field of the anomaly. (DS9: "If Wishes Were Horses")

In the Klingon confrontation at DS9 in 2372, General Martok charged that the station was using these same two tactics to give the appearance that the station was bristling with armaments; unfortunately for him, that hypothesis proved to be quite false. (DS9: "The Way of the Warrior")