An article on oil-company profits in the April 5 Business & Finance section incorrectly listed the 1981 capital expenditures and exploration budget for the Atlantic Richfield Co. Arco's 1981 capital expenditures budget actually calls for outlays of $4.1 billion, $2 billion of which is to be spent on exploration within the United States.

For the past year and a half, the nation's major oil companies have enjoyed a gusher of profits. Propelled by the 1979 jump in foreign oil prices and the lifting of price controls here at home, oil-industry earnings have surged to unprecedented levels.

In 1979, oil profits accounted for a third of all manufacturing earnings and two-thirds of their total increase from the previous year, according to a Citibank survey. Last year, with other sectors in a slump, oil earnings grew 13 times as fast as others, amassing 44 percent of the industry's total net income.

But the riches have proved an embarrassment as well, raising a spate of economic and social questions: What would the oil companies do with all that cash -- buy up department stores, as Mobil did in 1974? Can they really find much new oil? Is the industry amassing a disproportionate share of economic clout?

This month, details of the oil companies' 1980 financial reports are coming in, and the figures -- along with interviews with independent analysts who keep close tabs on the industry -- show that the profits picture, while eye-popping, is not necessarily as troublesome as some critics had feared.

For one thing, the 1979-80 spurt has come abruptly to an end. The industry is being squeezed between newly soaring oil costs and a reduced consumption, making it impossible to raise prices enough to maintain its profit margins. Most oil firms are expecting first-quarter declines, some as high as 25 percent.

Second, to the surprise of the skeptics, the oil companies have been spending well over 90 percent of their 1979-80 windfall of new exploration, drilling and refinery modernization, and it's beginning to pay off, particularly in development of share oil and discoveries of natural gas.

And contrary to some apprehensions, they're not scattering their money on unlikely acquisitions. The two most visible exceptions -- Exxon's 1979 acquisition of Reliance Electric Co. and Mobil's purchase of Montgomery Ward -- have proved conspicuously bad investments, not likely to be repeated.

What the oil companies have done with their remaining available cash -- still a gargantuan sum by most standards -- is to buy heavily into the related coal and mineral-extraction industries, businesses that themselves are now cash-poor and need capital for new equipment and modernization.

Over the past few weeks, there's been an avalanche of such acquisitions:

Sohio just doled out $1.8 billion for the Kennecott Corp., the nation's largest copper producer. Standard Oil of California is trying to take over giant Amax mines for $4 billion. And Seagram & Sons, the Canadian-based distiller now heavily into oil operations, tried to buy St. Joe Minerals Corp., ultimately losing out to the Fluor Corp.

The difficulty is, the rush worries some onlookers more than Exxon's purchase of Reliance did. Opponents fear the coal takeovers and investments in solar-technology firms will enable the oil companies to manipulate the nation's entire energy supply and possibly retard development of coal and solar power.

Henry M. Banta, former energy adviser to Sen. Edward M. Kennedy (D-Mass.), argues that the rush to buy up mining companies only goes to prove that the oil firms "simply can't spend all the money they're making" even with the sharp expansion in exploration, and he says the government oughtn't to countenance it.

Instead, Banta says, Washington ought to raise the windfall profits tax or require the oil firms to return the excess earnings to their stockholders, who then can invest in other ventures. If the ailing mining firms can't get capital through regular market channels, he asks, why should Big Oil provide it?

And Edwin Rothschild, director of the Energy Action Educational Foundation, argues that the oil giants' often-mixed performance in operating coal companies shows that, apart from the initial infusion of capital, their takeover of such ailing industries doesn't always help them to revive.

If anything, Rothschild charges, the oil companies tend to sit on competing forms of energy such as coal and solar-power to "balance them off" against petroleum, which is still their major profit source -- and interest. The movement of money to Big Oil, he says, is coming at the expense of other industries.

But other analysts caution it still isn't clear precisely how big a threat the rush to rocks actually is. The oil industry and the mineral extraction industries have been kissing cousins for decades. Oil companies got into the uranium and coal businesses long ago, and some even have bought copper mines.

Bernard J. Picchi, petroleum industry specialist for the Salomon Brothers investment house here, points out that mining is a natural for oil companies to use their expertise in geology and digging. The majors realize their oil won't last forever, and they have to diversify somewhere.

"What's happening is exactly what should be happening in an efficient business economy," Picchi says. "The oil companies don't want to spread out into fields that are too far removed from their expertise. And God knows the extraction industry needs the capital."

That the oil windfall so far has gone largely into new exploration is backed up by some impressive figures. Statistics show total drilling rigs now operating in the United States have soared to 3,582, a gain of 913 rigs, or 34.2 percent from a year ago and the 11th record week. In 1976, the number was 1,658.

The number of active seismic crews working within U.S. borders has quintupled over the past 12 months, topping the 600 mark this month for the first time in more than 25 years. Drilling of wildcat wells also has increased sharply. And U.S. exploration abroad also is on the rise.

Moreover, the increased exploration is beginning to hit pay dirt. Industry data show total oil production in the United States actually rose rather than declined in 1980 for the first time in recent memory, and 1981 promises more of the same. Projections for coming years show capital spending up even more sharply.

Leading the pack -- expectedly, because of its size and profits picture -- is the Exxon Corp., which alone will spend a staggering $11 billion for capital projects and exploration. That's almost as much as the entire federal energy budget, and the figure is up 38 percent from Exxon's 1980 total.

Standard Oil Co. of Indiana will spend $5.1 billion, a rise of 20 percent; Mobil, $5 billion, 27 percent above 1980's levels; Standard of California, $4.2 billion; Conoco, $2.9 billion; Arco, $1 billion. And in most cases, the companies' projections show even higher figures for coming years.

Should the industry be spending more of its money on exploration? Oil company spokesmen say the main reason they're not drilling more is the current expansion has caused such a crippling equipment shortage. In some cases, the companies also are constrained by limitations on drilling rights.

There also are serious concerns that the boom in new exploration may be unnecessarily bidding up drilling costs. Industry statistics show the price of drilling rigs and other equipment soared 23 percent in 1979 and rose even more rapidly in 1980. Still another big jump is under way this year.

And future exploration costs will be pushed up even more rapidly by location and technology: The easy-to-drill domestic sites already have been explored. What remains are those in Alaska, the North Sea or offshore. The new frontiers are in oil shale and synthetic fuels, all costly to develop.

Moreover, Aivars Krasts, Conoco's vice president for planning, points out that besides spending for exploration, the oil companies also must spend billions to revamp outdated refineries so they can handle the new higher-sulfur crude that is beginning to flow from the Middle East and most newly discovered wells.

There's no argument that even with the hefty new exploration effort, the oil companies' cash-pot is enormous. Moreover, what shows up on the books doesn't represent all their buy-up power, by any means. The industry also has spectacular borrowing ability -- and in most cases, that has barely been tapped.

Jack, F. Bennett, Exxon's senior financial officer, predicted in an interview that the industry's investment will increase so rapidly that even with current profit levels, his own firm -- and other majors -- soon will be spending "a lot more than they can generate internally" and will have to borrow heavily.

And Picchi expects more and more oil companies to have to go to the stock market to obtain expansion capital. Only two or three did so in 1981, evidence of the industry's flush position. But the number this year "could be double," he says.

Nevertheless, the current profits figures obviously still are embarrassing to some companies. Although Exxon and Conoco executives were willing to talk openly about their firms' financial pictures, Mobil and Standard of Indiana refused to discuss the issue. Company spokesmen insisted no one was available.

Must the government cut back its "windfall profits" tax, as the industry keeps contending, to boost exploration? Most analysts say no. Oil executives are hard put to prove they'd be drilling much more if the tax weren't there. And the industry is doing well, despite the extra levy.

Indeed, by most reckoning, the long-range outlook is for continued high profits, although the gusher is slowing. And if the government speeds up gradual removal of the remaining controls on natural gas prices, there could be a new profits explosion again.

For now, however, bloated inventories and sagging demand worldwide have caught the industry in a box: Crude oil prices are soaring anew. Refinery costs are rising sharply. And, thanks largely to previous price hikes, domestic oil consumption is on the decline, making new price increases difficult.

As a result, the industry's latest squeeze will continue through much of 1981. The outlook is that Big Oil still will be highly profitable this year and next, but not quite as awash in earnings as it was in 1979 and 1980. The gusher has been temporarily capped. And the fallout hasn't been as bad as expected.