The same way a .22 caliber round from a rifle would not leave a crater in a marshmallow with a 1000 ft. diameter. It would pass clean through.
Lots of mass, lots of velocity --- how does this NOT generate a big crater?
The cross sectional area is small. It can only impart so much momentum to the stuff it knocks out of the way. The several kton TNT equivalent is distributed along a long thin string within the earth, it's not all localized at some point. The thing travels at 250 mile/sec and at 0.1diameter of a human hair there's not a lot you'd find at the surface. Maybe they'd find a long thin glassy rod of rock, extending from the entry point down twords the molten core.
It's a different kind of matter that doesn't interact in the same way as meteorites.
The same way a .22 caliber round from a rifle would not leave a crater in a marshmallow with a 1000 ft. diameter. It would pass clean through.
It depends on how much energy is actually transferred to the earth. A tiny object can zip through only using a bit of its energy, but enough to cause a localized earthquake. If, however, something managed to STOP the thing dead in its tracks, the resulting crater would probably be quite impressive!
Also, you have to be careful when nuclear scientists talk about 'massive' particles. To them, that might mean it weighs a millionth of a microgram. Massive... if you are used to talking about protons! In this case though, they are talking about things weighing in the neighborhood of a ton, so I think that qualifies even for us macroscopic types.