A federal judge on Wednesday blocked the Obama administration’s first major regulations on hydraulic fracturing, a technique for oil and gas drilling that has led to a boom in American energy production but has also raised concerns about health and safety risks.

The United States District Court for Wyoming issued a preliminary injunction preventing the Interior Department from carrying out the rules, which were issued in March by the department’s Bureau of Land Management. The ruling, however, stops regulations aimed at only a small fraction of the nation’s domestic oil and gas production.

The Interior Department began drafting the rules, focused on drilling safety, in Mr. Obama’s first term after breakthroughs in the technology, also known as fracking, led to a surge in the production of oil and gas.

The rules were the Obama administration’s first effort to regulate fracking, but they applied only to oil and gas production on federal and tribal lands. The vast majority of fracking in the United States — almost 90 percent — is done on state and private land and is governed by state and local regulations.