Hello friend, first of all I want to thank you for reading and commenting on this post, that is very valuable for me, I will gladly answer your question.

If you do not take corrections and lower the fluid density, in the event that the density increases above the values indicated by the drilling program, you can run the risk of fracturing the formation, since the formation has a maximum allowable pressure to fracture.

The density of the drilling fluid is a property that in its increase makes the hydrostatic pressure it exerts on the walls of the well increase, and in many cases the hydrostatic pressure of the drilling fluid may be higher than the maximum allowable pressure that the formation accepts to fracture.

If the formation fractures, all the drilling fluid will escape from the well through those channels or breaches resulting from the fracture of the formation.

As all the drilling fluid escapes, the hydrostatic pressure exerted by the drilling fluid on the walls of the well will decrease to the point where it is lower than the formation pressure, so if the formation pressure is higher than the hydrostatic pressure of the drilling fluid then fluids such as oil and/or gas can migrate from the bottom of the well to the surface, and this combined with the friction at the surface and with the oxygen present can cause an explosion or what is called in the oil jargon as a blowout.

Therefore the drilling fluid density values can not be too low or too high, so they should be kept in a range dictated by the design of the drilling program of a particular well to be drilled.

Greetings friend and I hope I have answered your question effectively.