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It's an interesting question, for which the answer is broadly “yes, its theoretically possible, but rather unlikely, and none have yet been identified”. I’m making a distinction here between ejecta from impacts on earth that have been re-distributed but didn’t make it into orbit; versus material which was at least temporarily thrown high enough to be classed as “re-entry” material.
The potential name for such meteorites (if they exist) has been proposed as “Territe” and such territes will not be recognizable from simple observations of their lithology or geochemistry. They will have the same mineralogies as other Earth rocks and the only diagnostic feature would be a fusion crust formed during re-entry. However, this would not develop on many of Earth’s sedimentary rocks.
From a theoretical point of view the minimum crater size on Earth to produce such meteorites would be around 25km diameter and the launch velocity of the ejecta would need to be around 75% of the impact velocity. That would exceed most published estimates for imacts. Spallation could launch solid material at high velocities from a narrow and very shallow zone around the impact site, with vaporisation of volatiles in the target rock perhaps providing further acceleration.
For the high shock pressures associated with a suitably large Earth impact, any potential meteoroids would be small (probably <20cm diameter) and that also has implications for their survival during re-entry. Under typical re-entry conditions, most meteoroids from outer space need to be at least the size of a basketball for anything recoverable to reach Earth’s surface.
Confirmation of a meteorite of terrestrial origin would come from more detailed analysis of its isotopic state and anything from Earth would also be expected to have a relatively short Cosmic Ray Exposure age. I have a small specimen of NWA 6077 (possibly paired with NWA 5363 and NWA 5400) acquired some years ago, which created much excitement in that it had isotopic features which indicated it might be a territe. It classifies as an ungrouped achodnrite with brachinite-like mineralogy, but the oxygen isotope ration plots on the “Terrestrial Fractionation Line” (TFL).
The TFL plot is Indistinguishable from terrestrial rocks. Sadly, the Earth isotopic similarity is not seen for all elements. In particular, while there is observed similarity in O, Ni and Cr between the meteorite and terrestrial material, other elements such as Ca, Ti, Mo, and Ru are isotopically distinct from Earth materials. The parent body (or bodies, since the three paired meteorites exhibit some differences) remains a mystery, save to say that it had a number of Earth-like isotopies.
There is one other possible terrestrial meteorite that I know of but, although it may have come from Earth, it was found on the Moon. Examination of a piece of rock collected during the Apollo missions (Apollo 14 Lunar Breccia 14321) has indicated that it contains felsite fragments which formed under conditions not found on the Moon, but which are common on Earth.
Bear in mind that, if territes exist, we’re more likely to find them on the moon due to it proximity the Earth and the fact that it doesn’t have an atmosphere capable of causing shock-detonation or destructive ablation in the way that Earth’s atmosphere does
If your question is really “could these large chunks of rock I’m picturing be territes (from the Chicxulub impact or anywhere else)?” then I’m afraid the answer is “no”. They seem to be terrestrial conglomerates with no evidence that they’re impact-related..
