In Libya, life seems to go on as usual. Many Americans in Libya are ignoring Reagan's orders to leave, and many Libyans are ignoring Colonel Qaddafi's anti-US rhetoric

United States pressure on Libya's Col. Muammar Qaddafi for his alleged support of terrorism has so far done little to damage the Libyan economy, already shaken by falling oil prices. A week's survey here -- before and after the Feb. 1 deadline when economic sanctions announced by President Reagan took effect -- shows that the daily interests and cares of ordinary Libyan citizens are far removed from the anti-United States and anti-Israel political rhetoric of Colonel Qaddafi. Mr. Reagan announced the sanctions in early January, after Palestinian terrorist attacks at Rome and Vienna airports last December claimed 19 lives. The US and Israel said they had proof that Libya was supporting the terrorists.

On a day when Palestinian guerrilla leaders at a Tripoli news conference threatened to retaliate against US and Israeli planes for Israel's Feb. 4 interception of a Libyan civilian jet, a Libyan professional (who asked to remain unidentified) said his main concern was ``finding food and clothes for my family.''

Few retail shops and only one restaurant remain open in this capital city. Qaddafi's governing General People's Congress, which is due to hold its annual session here in March, has outlawed shops where even one Libyan is employed by another Libyan not of his own family.

Government shops, supplied by faulty ``socialist'' distribution networks, offer pitifully few necessities. They mostly display vast expanses of empty shelves.

Libyans and foreigners, including hundreds of Americans disobeying Mr. Reagan's Jan. 7 order to leave, drive daily into the countryside surrounding Tripoli to buy chickens, eggs, fruit, and vegetables from farmers who peddle their own crops by the roadside.

Sinking oil income is causing Libya to ``desperately seek ways to get rid of oil by barter deals or whatever,'' in the words of a European diplomat.

Western experts say Libyan exports have fallen by about 23 percent, from 1.1 million barrels per day to around 800,000 barrels per day since Reagan forbade US oil companies from operating in Libya.

Of the estimated 1,500 American resident workers and their families whom Reagan ordered out by Feb. 1, an estimated half either never left or did leave, briefly, and have since returned.

A woman from Detroit, Mich. -- who like other US ``illegals'' declined to give her name -- was registering at the Belgian Embassy, which protects US interests here. She applied for a ``Prohibited Transactions'' permit from the US Treasury Department.

``I've lived here 10 years with my Libyan husband and my nine-year-old son, who was born in Michigan,'' she said, laughing. ``I have no intention of leaving just because Mr. Reagan has taken a dislike to this country, and [I have] no reason to do so. So, as you see, I'm applying for a permit to buy groceries in Libya!''

All financial transactions by Americans in Libya, including purchases of food, now require such a license. Some of the Americans say they will challenge the constitutionality of this in US courts.

Many who left before Feb. 1 simply flew to the island of Malta, where the nearest airport is, and then returned to Tripoli. Some of them, mostly oil technicians, said they kept weekend homes in Malta and commuted back and forth anyhow.

Four US oil companies, Occidental Petroleum, Continental Oil (Conoco), Marathon Oil, and Amerada Hess, are in a quandary about the fate of about $1 billion in assets here -- now that neither the US nor Libya allows them to drill for oil here. Unless they can find a way around the ban, Libya could nationalize and seize all these assets.

The other companies are waiting for a US Treasury ruling to clarify whether European subsidiaries can lift the Libyan oil entitlements of the US firms. Some diplomats believe the US Treasury and White House will deliberately withhold clarification ``to let the companies stew in their own juice with Qaddafi,'' as one put it. The Treasury temporarily extended the Feb. 1 deadline to give the companies more time.

Libya formerly had guaranteed European outlets for its crude oil through the American firms' European refineries and subsidiaries. But now, Libya's national oil company must sell oil directly.

In order to make this easier, Libya reportedly agreed with Algeria and Iran to lower official contract prices from $30 to $26 a barrel. The agreement came at a meeting Feb. 5 and 6.

Algeria denied this, but oil analysts here say it was probably true and intended to ease barter deals, such as those between the Soviets and Libya. The Soviet Union, Libya's ally and its main arms supplier, reportedly pumps more than 120,000 barrels per day. It writes payments for this oil off Libya's debt of more than $10 billion for Soviet arms and military equipment.

The Soviet Union resells the oil at a profit on the European spot market. Since spot prices have already fallen to $16 a barrel or less, the Soviets are not keen about Libyan offers to renew former barter deals using a $20 price.

``The big question,'' says an oil industry specialist, ``is what will happen to the 300,000 bpd [barrels per day] the US companies were lifting [producing and exporting]? Libyan storage tanks are now filled to overflowing. Many are badly maintained and leaky. The whole system is operating far below peak efficiency, and the demand for oil in Europe grows less all the time.''

``If the US really chooses to follow through on the Reagan sanctions,'' explained one European whose government, like other European Community members, declined to follow the US measures, ``the Reagan administration could make things very tough for Libya.''

``But,'' he continues, ``that would mean paying really close attention and barring the import and use of imported US-patented oil technology, which is what makes the Libyan oil industry work.''

``We doubt that the US administration will do this. If, on the other hand, the Reagan administration looks the other way and permits the oil companies to let their European subsidiaries lift their oil, the impact on Libya will have been practically zero. In that case, why bother to have imposed sanctions at all?'' Mr. Cooley, an ABC news correspondent based in London, is a former Monitor correspondent who specializes in the Mideast and north Africa.