'deep repercussions' is a correct and usable phrase in written English.
You can use it to refer to a situation in which the consequences of an event are more serious or far-reaching than expected. For example: "The oil spill will have deep repercussions for the environment and the local economy."
The changes may have deep repercussions for the United States.
The decision of which gear to use in a given situation can have deep repercussions.
The US has set the stage by keeping a distance – an approach that has had deep repercussions.
For Iraq, the events in Syria have deep repercussions, centering on the fact that the Syrian opposition forces are seeking to achieve a mirror image of what occurred a decade ago in Iraq.
"The resignation of Carlos Alvarez as vice president has sown a profound crisis in the governing alliance," said an editorial published today in the country's largest-circulation daily, Clarin, "which has deep repercussions for the country's political life and probably the economy as well".
How it ends will have deep repercussions for decades to come.
It is in the domestic arena, however, that the constitutional changes will have the deepest repercussions.
But because Mr. Nicholas is on parole, the arrests could have deeper repercussions.
People prefer physical books, not out of old-fashioned attachment but because the nature of the object itself has deeper repercussions for reading and comprehension.
Although many people blame the terrorist attacks on the twin towers and its fallout on Afghanistan as the major cause behind the terrorism, there are deeper repercussions of this whole phenomenon.
"If history is a guide, the fear of deep political repercussions I don't think the data bear that out," he said.
