Scientific theories have stated that the dinosaurs were killed by a meteor collision which subsequently triggered great catastrophic events such as a gigantic smoke mushroom that obstructed sunlight from reaching the planet for decades. But this is just a hypothesis.
Now the truth is what I'm going to tell you, don't believe everything that science tells you, it's all "hypothesis"; what actually happened was that when the tectonic plates detached, it triggered massive earthquakes never seen before with devastating proportions, which buried a large part of the dinosaurs, and shortly after, devastating tsunamis.
So friend, if you believe it was a meteor that collided with the planet, I'm sorry to tell you, but you are completely mistaken.
That huge hole in Mexico is nothing more than human excavation.
And it's recent; they made that huge crater to collect rainwater because there was a civilization that inhabited that place.
So forget about the idea that dinosaurs were extinct by meteors or comets, whatever.
None of this is true, what happened was that Pangea was divided into several continents and the side effect was earthquakes and tsunamis that devastated life on Earth.
And for you, does my thesis make sense? $USUAL