volcanic feature volcanic dike An intrusive igneous body. Its thickness is usually much smaller than its other two dimensions. Thickness can vary from sub-centimeter scale to many meters in thickness and the lateral dimensions can extend over many kilometers. A dike is an intrusion into a cross-cutting fissure, meaning a dike cuts across other pre-existing layers or bodies of rock, this means that a dike is always younger than the rocks that contain it. Dikes are usually high angle to near vertical in orientation, but subsequent tectonic deformation may rotate the sequence of strata through which the dike lies so that the latter becomes horizontal. ENVO ENVO:00000498 FTT:654 dyke (geologic) ridge volcanic dyke igneous dike igneous intrusion dike