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How do vaporized, melted, and crushed rocks form around an impact site?

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four impact craters — Meteorite crater Four impact craters of the same size (30 km [20 miles] in diameter) imaged by spacecraft on different solid bodies of the solar system and reproduced at the same scale. They are (clockwise from upper left) Golubkhina crater on Venus, Kepler crater on the Moon, an unnamed crater on Jupiter's moon Ganymede, and an unnamed crater on Mars. The images are oriented such that the craters appear illuminated from the left; the Venusian crater is imaged in radar wavelengths, the others in visible light.

When a meteorite strikes a planetary surface at hypervelocity, it releases an enormous amount of kinetic energy in a localized area, triggering a process similar to an atomic bomb explosion.1

Immediately upon impact, shock waves are imparted to both the surface material and the meteorite itself. As these shock waves expand outward from a point beneath the surface, they dissipate energy and create distinct zones of vaporized, melted, and crushed material. The extreme pressure and heat generated by these waves are responsible for the following transformations:1

Vaporization: The energy released is typically sufficient to completely vaporize the impacting meteorite.21
Melting: The intense heat can melt surface rocks, sometimes creating fused silica glass.13
Crushing: The shock waves shatter and deform the bedrock, often creating subsurface features such as shatter cones, which are conically shaped structures that radiate from the point of impact.3

Following the initial shock, a rarefaction (or release) wave causes pressure gradients that project this material upward and outward, forming the crater and the surrounding ejecta blanket.1