Motorists in the Washington area and much of the nation will not necessarily face new gasoline lines in the wake of President Carter's decision to halt Iranian oil purchases, industry analysts said yesterday.

Local officials, hoping that a new crunch like last spring's would not be felt here, decided not to immediately reimpose odd-even gasoline rationing.

"There really shouldn't be any need for lines if people don't panic and start topping off again," said Jack Werner, an official in the District of Columbia energy office.

In California, however, Gov. Edmund G. (Jerry) Brown Jr. said that he would reimpose the odd-even system next week.

The cutoff by Carter also is not expected to cause any shortage of home heating oil in the Washington area this winter. Industry analysts say stocks of heating oil here and nationwide are huge.

"I think we could make 'er right easy through the winter whether they turn off Iran or not," said Walter Meighan, president of Griffith-Consumers, the largest home heating oil distributor in the Washington area.

The only part of the country that may feel an impact from the cutoff of Iranian oil is New England, which is totally dependent on imported oil, industry analysts said. Even there, they said, there may be no impact unless Iran totally cuts off its world exports.

Prices of gasoline and heating oil, however, are another matter.

Many oil executives said they hope U.S. companies can make up lost Iranian oil imports by shuffling around oil from other sources. But they also say prices will continue to soar.

Yesterday, Dan Lundberg, a gasoline market forecaster, said that by the end of the year the average price of gasoline will rise an additional 16 cents a gallon, to a total of $1.17 a gallon.

A great deal of this increase, however would have taken effect whether or not oil supplies from Iran were cut off.

Last week, major oil company executives had said they expected the Organization of Petroleum Exporting Countries to raise prices another $4 or $5 a barrel at their December meeting.

An increase in the official cartel price of $5 a barrel would add about 12 cents a gallon to gasoline and other fuel prices. OPEC's price range for oil ranges now from $18 to $23.50 a barrel.

Spokesmen for most of the seven line to 1,300 of the 1,500 service stations in the Washington area said the oil cutoff probably would have only a negligible impact on gasoline and heating oil deliveries.

If Iran continues to produce the oil that normally would be delivered to the United States and sells it instead to other countries, that action would leave other oil-producing countries with more oil that can be directed to the United States, several oil men said yesterday.

"Providing Iran continues to produce and export at levels they have (worldwide), I don't see any impact except for an adjdustment in distribution patterns," said a Mobil spokesman.

At the same time, both the oil men, local officials and other expressed a watchful, cautious attitude.

"We're sure going to have to get back to conservation," said Glenn Lashley, a spokesman for the American Automobile Association.

Energy officials from the District, Maryland and Virginia said they will confer today or tomorrow on what action -- if any -- to take as a result of the cutoff.

"We're concerned about panic buying. We're hoping to head that off," said Gene Oishi, a spokesman for Maryland Gov. Harry Hughes.

Virginia energy chief George Jones said, "I think we can handle the cutoff of the Iranian oil without any major dislocation -- the sort of confusion and economic turmoil we had this summer. People know they can conserve, they know how to adjust their lives."

Nonetheless, Virginia energy officials sent telegrams yesterday to officials in nine Northern Virginia jurisdictions asking them if they want the odd-even gasoline rationing system reimposed. In another poll last week, when some lines started materializing at Northern Virginia stations, officials in the nine jurisdictions unanimously said they did not want odd-even imposed again.

On Capitol Hill last week during closed door sessions before the Senate Energy Committee, Energy Secretary Charles Duncan stressed that U.S. oil inventories are at comfortable levels.

The nation's primary stocks of crude oil and petroleum last week stood at 1,272 million barrels, which is about normal. Although gasoline stocks have dropped slightly senior administration officials said yesterday they were pleased that, during the four weeks ending Nov. 2, Americans used 8 percent less petroleum than they did during 1978.

Heating oil stocks, meanwhile are well above the administration's 240 million barrel winter inventory target.

The supply situation is further eased by the fact that it takes 6 to 7 weeks for tankers to ship oil from Iran to U.S. ports, and there is nearly a 45-day supply of oil on the seas.

John Lichtblau of the Petroleum Industry Research Foundation in New York, said, "the cutoff won't cause gas lines, and won't be a catastrophe." Like other oil executives, though, Lichtblau said, "I am not sure how easy it will be for the United States to pick up oil to replace lost Iranian imports."

Another noted analyst, Walter J. Levy, said in a phone interview that the key question is whether Iran will cut back oil production altogether in retaliation to Carter's announcement. "Ideally, if the Rianians continue pumping oil, will just be switched around."

Both Levy and Lichtblau, however, speculated that the National Iranian Oil Co. is likely to earmark oil formerly sold to American companies for shipment to the United States for direct sale to the spot market -- where oil is sold on a one-time basis instead of under longterm contract. If Tehran does move all of that oil to spot sales it will add upward pressure on world oil prices.

Last weekend one shipment of oil sold on the spot market was quoted at $43.50 a barrell almost twice the cartel's official price.

In recent days Energy Secretary Charles Duncan has said that, to prevent a disproportionate share of a possible cutdown in Iranian imports, he was ready to impose mandatory crude oil allocations. Under crude oil allocations, companies such as Ashland Oil or Amerada Hess, which are highly dependent on Iranian imports, would receive oil from other American majors such as Mobil, Exxon, or Sohio with oil to spare.

Yesterday Dan Lacy, an Ashland Oil spokesman said, "We'll be short by about 100,000 barrels a day, but will try to make it up from our suppliers." Ashland refines a total of 425,000 barrels a day at seven refineries in North Central and Appalachian states.

The company that will be hardest hit by the cutoff, however, will be Amerada Hess, which operates a 700,000-barrel-a-day refinery in the Virgin Islands. Oil industry sources say that Hess receives about half of its crude oil from Iran.

Last summer, at former Energy Secretary James R. Schlesinger's request, Amerada Hess supplies Iran with shipments of kerosene -- heating oil -- to avert a shortage in the politically troubled Persian Gulf state that was once OPEC's second-leading producer.

Other American companies that depend to a lesser extent on Iran are: Exxon, Mobil, Atlantic Richfield, Gulf Oil, Texaco, Charter, Mapco, Sun Oil, Marathon, and Standard Oil of California.

Earlier this year, when Hess was totally cut off from Iranian supplies, it was able to make up its losses by increasing shipments of oil from Alaska's North Slope.