First of all I've read the other posts and know what the effects of a black hole appearing on the earth's surface is. It goes through the crust, the tectonic plates break apart, volcanos appear everywhere and it moves around inside the earth. In my story a portal is opened up to an area close to a large black hole. Nobody can say the effects of gravity through a portal so I'm just going to treat it as having the strength of a 1mm black hole. It being a portal means the portal can be closed and end the black holes effect so it only lasts lets say 5 seconds. There are also powerful entities in that world that can control the elements enough to keep the tectonic plates from breaking apart and causing volcanoes everywhere. What I want to know is the visual effects on nearby landmasses on a map if a 1mm black hole existed for only 5 seconds, ignoring the effect on the tectonic plates on the rest of the world. Let's say, a distance of 1000-2000 km is what I'm wondering about. Would the land be caving downward because of the black hole? Would they be going in a spiral pattern toward where the black hole is? How much of the oceans water would be drained in that time? Would all the plant life at the distances I provided be destroyed? How far down would the black hole get in the 5 seconds or even in 10 seconds and if it gets to the mantle in that time? Let's say it landed in the Cayman islands, the effect it would have on Cuba and Mexico. Again, this information is so I can figure out how a map would look after the event happened. I don't know how to say this without sounding like I'm ignoring facts, but any effects of the black hole existing for 5 seconds that would destroy the entire earth is probably controlled so it doesn't in this situation. I only want to know how it changes the areas close to it. Lets say the land above is still affected and only the tectonic plates below are held intact.
This is a very important question to me, I'm not giving any of these specifications for no reason. This is not made for the same purpose as the other black hole question, and my last one was closed. I am sorry if this is too hypothetical and it goes against the rules