'immense mass' is a correct and usable phrase in written English.
It can be used to refer to a large amount of something, often used to describe physical objects such as a huge mountain or a vast body of water. For example, "The immense mass of the mountain was breathtaking and awe inspiring to see."
And the big whales, the leviathans — how to explain their immense mass?
In his 1889 treatise "Regimental Losses in the American Civil War, 1861-1865," Fox presented an immense mass of information.
This simple idea was backed with an immense mass of well-documented detail and, at times, a memorable skill in sketching character.
The 20th century witnessed an immense mass of the oral literature of preliterate peoples and of the writings of all the great civilizations translated into modern languages.
The Lafayette, being an "immense mass of iron" bearing heavy guns, would have a coal barge and the General Price, a captured Confederate ship, double rafted to it.
His most important works for his royal patron are to be seen in the immense mass of screens and gates with which he embellished Hampton Court palace.
Indeed it is: among the theory's predictions was that violent events in the universe involving immense masses – such as the collision and merging of two black holes – could set the fabric of spacetime ringing, the ripples spreading across the cosmos and stretching or squeezing space as they pass.
Processing immense masses of data allows more efficiency or more convenience.
And then, all of a sudden, I heard this long, low moan, swelling until it became immense, a huge mass of sound that destroyed our furniture and blew apart our walls and then the whole neighborhood and left me all alone.
A vet who carried out a post mortem on the animal commented on its "immense muscle mass and definition", the court was told.
Aristide had become the leader of an immense, protean mass movement that since the early eighties had been struggling--now by revolution, now by election--to seize power from Haiti's longtime rulers.
