Based on the fact that field geological observations, works to expose and geophysical exploration, discovery is located in the North China block before the southern edge of East Qinling 215.6Ma the ruins of an ancient earthquake's epicenter. The studies show that the the earthquake ruins formation depth greater than 10km the MS magnitude greater than 7. Geological, geophysical and engineering to expose the to combine rock geochemistry, isotope tracer isotope dating, REE and trace element characteristics analysis showed that the earthquake ruins by magma differentiation gas-liquid fluid to accumulate enormous pressure cryptoexplosion the fracture within formation.Focal discovery of the ruins and the formation mechanism of understanding of the significance of: the initial recognition of the presence of magmatic gas-liquid cryptoexplosion causes earthquakes, and thus improve the cause of the earthquake is tectonic earthquake causes explain ways to explore and improve the earthquake prediction; overcome seismogenesis research in theseismic source is not visible and not enter into the problem, and for the earthquake causes even earthquake prediction exploring direct observation of the focal entity. The earthquake ruins, the remains of the ruins of a focal, and is likely to be found so far, including a focal entity, the focal depth of the era of seismic intensity (magnitude) occurred, including elements of the most complete earthquake epicenter ruins.