The ground or the entire planet cannot remain in its current form anywhere near a black hole. There would be no ground for the black hole to sink to.

Besides wouldn't the 'ground' gravitate towards the black hole than the other way around?

For the black hole the ground is merely more dense vacuum, the ground has barely enough time to move if it comes in at interplanetary velocities (50km/s+), so by the time the ground will begin to react to the intense gravity, the black hole will have passed through with the force of a few hundred nuclear explosions.

At 6000 km away the gravity at the nearest surface of earth is zero.

1 minute (at 50km/sec) later it would be 3000 km the acceleration 4.5G or so.

1.5 minutes later it would 1500 km away the acceleration would be 17G or higher.

2 minutes later it would be on the surface, and everything ripped up (including buildings, soil, bedrock, crust, and the magma below would go from being accelerated up at incredible velocities to an even more intense acceleration down.

Over that 2 minutes the black hole is going to chew the hell out of the earth for 1000s of km in all directions and that's just the start of the fun.

As it hits the surface everything within 1000km will be experiencing 40G. The pressure waves will go from negative (as the black hole pulls the atmosphere away from the earth) to a HUGE over pressure as magma, bedrock, and water get slammed back down into the earth at 40G. Said over pressure wave of intense heat and pressure will expand outward from the point of impact and create problems world wide.

Worse on the opposite side it will just take a large chunk with it (approximately the volume of which the black hole has significantly more than 1G of gravity) which could easily take a continent with it, or say most of the pacific ocean.

I could see ocean levels and air pressure lowering significantly. After all why would the air stick around a 1G planet instead of a more than 1G black hole?

The area from which the air is removed is likely to be somewhere around 12,000 km wide (the area of which the black hole applies more than 1G).

So I'm not sure I believe the "barely enough time to move" thing when for minutes the accelerations will be crazy.

Not to mention that anything with 9mm would accelerate at the speed of light to the singularity. So while moving through the earth it wouldn't meet any resistance at all.

What do you think the density of a black hole is? :)

Almost certainly not actually infinite in reality :)

We treat it that way because, despite it showing that our model of physics is breaking down at that point, it works really well for most real purposes. But look at string theory, loop quantum gravity, etc., and you will find plenty of the variants within those umbrellas do not have a singularity at the heart of black holes.