Gasoline and home heating oil prices in the Washington area have jumped dramatically -- as much as 6 cents a gallon in the case of Exxon regular gasoline -- in the wake of Saudi Arabia's $6-a-barrel crude oil price increase announced last week.

That increase, matched by Qatar, the United Arab Emirates and Venezuela, is considered moderate and only a part of worldwide price increases now being worked out in Caracas at a meeting of the Organization of Petroleum Exporting Countries.

The announcement by Saudi Arabia, which supplies about 20 percent of U.S. crude oil imports, had these immediate effects on Washington area consumers:

Exxon, and Aramco oil producing partner that depends heavily on the Saudis for crude oil, announced yesterday a 6-cent-per-gallon gasoline price increase. The announcement has enormous impact here, where Exxon controls 24 percent of the gasoline market and has had some of the cheapest gasoline prices in town -- as low as 90 cents a gallon for regular at some large stations.

Texaco, another Aramco partner, announced a 3-cent gasoline price increase last Saturday, following the Saudi announcement. Texaco has about 5 percent of the gasoline market here.

Home heating oil prices here just jumped 2 percent in what oil heat distributors say in another effect of the Suadi move. Ten of 15 heating oil companies monitored by The Washington Post registered increases this week after at least two months of steady prices.

It may take a few days for Exxon's 6-cent increase to be passed on to consumers, because dealers are supposed to sell what they already have in their tanks at the old prices.

Some dealers -- as they have in the past -- may immediately raise prices in anticipation of the higher price they must pay when the next tank truck of gas is delivered to them.

The price increase by Exxon will bring its stations in line with Amoco and Gulf, the other big retailers here with 26 and 13 percent of the market, respectively. Both have been 10 cents a gallon or more higher than Exxon for some time.

Exxon was able to keep its price low because of the low price of Saudi crude it was getting and because the Saudis demanded that the saving be passed on to the American public.

The new round of oil price increases resulting from the OPEC meeting is expected to lift the price of gasoline here and nationally at least 15 cents more a gallon by late next year.

The Saudi price increase was also active to Nov. 1. An Exxon spokesman said that fact, "coupled with mounting increases in operating costs made it inadvisable to further delay the price changes."

The new average price of home heating oil in Washington is 90.22 cents a gallon -- up 1.78 cents on average since last week, according to the survey by The Post. The highest increase was 6.7 cents a gallon at the lowest was a penny a gallon.

These increases come on top of a 50-to-100 percent increase in heating oil prices here and nationally during the last year.

While prices are rising, supplies of gasoline and heating oil remain adequate, according to industry representatives. There will be slightly more gasoline available this month than last, and heating oil stocks have been kept high by warm weather and conservation.

Joe Amato, a Silver Spring heating oil dealer, said consumers appear to be mindful of uncertainties of both prices and supply, and are using from 5-to-8 percent less heating oil than normal, even after figures are adjusted for the unseasonably warm weather.

Many of the heating oil prices increases here in the week also appeared to be triggered by Exxon, which included a 3-cent-a-gallon increase for home heating oil with its gasoline announcement yesterday.

Metropolitan Fuels Co., a large Bethesda oil distributor exclusively supplied by Exxon, which has had the lowest price in town -- 82.2 cents a gallon -- for months, yesterday raised its price to 86.96.

Griffith Consumers, the largest home heating oil distributor here, held firm yesterday at its price of several months -- 88.9 cents.

"We've been on a program to keep our prices [down], but sooner or later [OPEC price increases] are going to affect everybody in the industry," said Griffith President Walter Meighan.