Iranian oil production - the lifehood of this troubled nation's economy - increased only slightly yesterday as the government intensified its pressure on striking oil workers in the hope of at least meeting domestic needs and averting the economic chaos that seems imminent.

However, the civil unrest that had threatened to topple the government of Shah Mohammad Reza Pahlavi has spread to other sectors of the economy. Informed observers said the survival of the government may well depend on the shah's ablility to put an end to the oil strike before the loss of export oil revenue combines with the effect of other labor disruptions to put Iran's economy in total disarray.

One knowledgeable official termed the oil strike only a manifestation of a "rolling disaster" in Iran's economy.

A cycle of industrial and service industry strikes, followed by generous wage settlements that have encouraged more strikes, is more ominous in the long run than what could be a short-lived oil workers strike, he suggested because it could lead to a long period of nearly anarchic conditions and the eventual imposition of military rule.

Agriculture reportedly is feeling the effects of labor turmoil with sugar beets rotting in fields and export foods piling up in depots. There have been no official estimates of national output losses in all sectors of the economy, but oberservers said total Iranian production may have dropped by half in recent weeks.

A strike by Iran Air continued last night forcing the cancellation of all the airline'sdomestic and international flights and discrupting other service at Mehrabad International Airport outside Tehran.

There were scattered clashes between protestors and the military in the capital yesterday, including a brief confrontation between rock-throwing anti-shah demonstrators and police at Tehran University.

Hoping to shorten the ioil worker's walkout and foster a sense of normality, the government sent troops into the refineries and oil fields yesterday for the third day in a row to "encourage" the return of employes.

Government officials were said to be warning the 30,000 workers about penalties that can be imposed for ignoring back-to-work orders, and Iranian troops were attempting to assure easy access to the production fields for those willing to work.

The National Iranian Oil Co, has revealed little about the situation in the fields, but informed analysts said Iran's oil production has climbed steadily to about 2 million barrels a day, just over a third of its normal production of 5.8 million barels daily. After the first day of the walkout, production dropped to only 1.1 million barrels.

Officials said current production is enough to meet domestic needs and avert the kind of panic that spread last week when rumors of an oil shutdown caused motorists to beseige filling stations.

But more important in the long run is the effect on Iran's $21 Billion-a-year export revenue, which accounts for 60 percent of the country's gross national product.

Even before the strike, Iranian officials were forecasting a $1.5 billion deficit and saying there would be severe economic repercussions unless the Organization of Petroleum Exporting Countries, substantially raises prices at its Dec.16 meeting in Abe Dhabi.

While only two months ago the oil-producing states seemed willing to settle for a 5 percent increase, analysts are now talking about a figure closer to 10 percent. This would cost consumers $20 billion a year.

Iran's oil revenue is particularly critical now because after granting generous wages increases in many industries during the past two months to quietlabor unrest, the government gave 900,000 civil servants a 25 percent wage increase, plus fringe benefits, at an annual cost of $1.5 billion.

Iran has an $11 billion oil reserve into which it could dip, and borrowing capacity as well. But the specter of spiraling expenditures and, subsequently, rapid inflation worries government economists.

The quick wage settlement, some political observers believe, is a symptom of the shah's tendency to govern by crisis mangement-reacting to events rather than controlling them.

The shah's conservative critics-particularly those in the military and industrial establishment-complain that the government's acquiescence to wage demands has fostered even more demands, which have acquired a political flavor.

The striking oil workers, who recently won a wage increase, are now demanding political concessions, including an end to martial law in 12 cities and immediate freedom for all political prisoners.

The government last week freed 1,126 prisoners on the shah's birthday, and said it will release another 1,000 on Dec.10, World Human Rights Day.

The 4,000 striking airline employes are similarly demanding political-rather wage-concessions. They have called for the the immediate release of all political prisoners, elimination of job discrimination, punishment of the airline's former managing director and an end to pegging of the rial to the dollar.

They are also demanding the firing of all foreign employes, a condition that officials says is becoming more common in labor negotiations.

In the case of the oil workers' strike, the national oil company says it is powerless to negotiate political demands, although the oil company's chairman Hushang Ansary met with the shah earlier this week to discuss the crisrs.

As further evidence that the government is reacting rather than leading, the shah's cities point with mixed feelings to the government's policy of permitting mass demonstrations and restraining military commanders, even though martial law now in effect in cities prohibits political gatherings of more than three persons.

While the order has a humanitarian result, the critics say, it is the kind of reaction to events that conjures visions of a monarch on the run and thereby leads to further antigovernment demonstrations.

On Wednesday, tens of thousands of demonstrators marched in defiance of martial law from Tehran University through downtown Tehran to commemorate the 16th anniversary of the exile of the Shiite Moslem religious leader, Ayatollah Khomeini.

Moreover, the government has lifed censorship on Tehran's newspapers-also in reaction to strikes and demonstrations against press suppression-and this has resulted in free-wheeling coverage of anti-shah activities. On Wednesday, newspapers carried lenghty interviews with freed political prisoners who gave chilling of SAVAK, the secret police.Such coverage normally is unheard of in Iran.

Behind the strategy of these new freedoms, political observers say is the shah's hope that moderate Iranians will tire of the civil unrest and countenance an authoritative and final crackdown on dissidents whenever the shah decides to order it.

Short of that, a compromise between the moderate opposition and the shah, leading to some form of interim government until the promised elections in July, would appear to be the only alternative to a military government in Iran.

Most political observers here believe that if the dissidents hold out for the kind of Islamic socialist republic that Khomeini demands, instead of the constitutional monarchy proposed by some moderates, the resulting economic and civil chaos will lead inevitably to military rule.