NEW YORK, AUG. 14 -- The stock market closed out a week of dramatic gains and record trading volume by posting a modest decline today.

The Dow Jones average of 30 industrials slipped 6.06 to 2685.43, but nevertheless finished the week with a gain of 93.43 points. That surpassed the previous record weekly advance of 92.91 set the week that began March 10, 1986.

Volume on the New York Stock Exchange came to 196.12 million shares, down from 217.07 million Thursday. The week's total turnover of 1.11 billion shares also represented a new high.

The Dow Jones industrial average, which first crossed the 2700 level at midsession on Thursday, spent part of today's session above that point before pulling back.

Before the market opened, the Commerce Department reported that the nation's merchandise trade deficit widened in June, with imports exceeding exports by $15.71 billion.

The figure came in well above most advance estimates on Wall Street, and disappointed traders who had been hoping for evidence that the dollar's long decline from early 1985 through this spring had begun to improve the competitive position of U.S. industry in world markets.

The news sent interest rates higher in the bond market, offsetting enthusiasm over the successful completion Thursday of a Treasury auction of bonds and notes.

However, as stock prices fell at the opening, brokers said they attracted buyers who had been waiting for an opportunity to get in on the bull market, which passed its fifth anniversary this week. The rest of the session was pretty much a standoff between the bulls and bears.

CNW was the day's standout performer, jumping 13 1/8 to 39 1/4. The railroad holding company said it was talking with several other parties about a possible sale or restructuring.

Newmont Mining rose 2 3/4 to 79 3/4. An investment group including Mesa Limited Partnership has acquired 9.1 percent of Newmont's stock and indicated that it might increase its position.

Niagara Mohawk Power led the active list, down 1/8 at 15 1/4 on volume of more than 10 million shares. Analysts attributed much of the activity in the stock to strategies by traders seeking to capture the company's quarterly dividend.

Auto stocks were strong, aided by some recent upbeat sales figures. General Motors climbed 2 to 93 1/2; Chrysler 3/4 to 45 1/4, and Ford Motor 3/4 to 109 7/8.

Nationwide turnover in NYSE-listed issues, including trades in those stocks on regional exchanges and in the over-the-counter market, totaled 230.84 million shares.

Standard & Poor's index of 400 industrials lost 1.21 to 389.38, and S&P's 500-stock composite index was down .66 at 333.99.

The Nasdaq composite index for the over-the-counter market edged up .06 to 451.61. At the American Stock Exchange, the market value index closed at 363.61, down .40.