Only about half of the 32 teams that eventually will play in the NCAA Basketball Tournament have wrapped up berths entering the final week of the regular season.

In past years, most of the playoff field already had received bids by this time. But the NCAA Basketball Committee decided this season to wait another week (until next Sunday) before determining the tournament alignment.

Of the 18 conferences that get automatic sports in the tournament, only the West Coast Athletic Conference (San Francisco) can name its league representative today.

Michigan in the Big 10 and UCLA in the Pacific Eight have all but wrapped up their league titles but still have pivotal games left. Otherwise, the remaining conferences either will stage tournaments this week to determine an NCAA representative or facr the possibility of needing a playoff to break first-place ties.

North Carolina, which won the ACC regular-season crown, is assured of a bid, and it seems likely that independent Nevada-Las Vegas and such conference teams as Utah, Arizona, Tennessee, Kentucky, Cincinnati, Louisville and Arkansas will be in the tournament either as champions of as at-large representatives.

This is how the four NCAA tournament regions stand entering the final week: EAST

(Five league champions, three at-large berths)

Penn and Princeton are tied for the Ivy League lead, each with four conference games remaining. Both must play Columbia, the third-place team, on the road.

The Southern Conference playoffs end Wednesday night. The favorites will be Furman and VMI, regular season co champions. Furman has about well the last few weeks, although VMI won the only meeting between the two.

Unless a dark horse like North Carolina State or Maryland wins the ACC tournament, the two most likely ACC representatives will be North Carolina and Wake Forest. Clemson, which normally would be a major contender for a bid, is ineligible for the NCAA playoffs. The ACC Tournament winner plays in the East, and the league's at-large school probably will wind up in the Mideast Region.

Rutgers and Villanova are the top choices in the Eastern Collegiate Basketball League tournament, which also includes George Washington, Hofstra, Temple and Lafayette all have a legitimate shot at taking the East Coast Conference playoffs.

Possible at-large teams in the East include the SEC runner-up (Tennessee or Kentucky) and one of the ECAC tournament winners. MIDEAST (FOUR CONFERENCE CHAMPIONS, FOUR AT-LARGE TEAMS)

Even if Michigan winds up tied with Minnesota for the Big 10 title, the Wolverines will go the Mideast since Minnesota is ineligible for the NCAA Tournament. Big 10 officials say, however, that the NCAA would not take the third-place team, most likely Purdue, as an at-large school.

The Tennessee-Kentucky game Saturday in Knoxville will determine the SEC champion Saturday. If Kentucky, which leads by a game, loses, then the two will tie and a playoff will be held. If Kentucky wins, the Wildcats will play in the Mideast (held on their home floor) while Tennessee will be an at-large team.

The Ohio Valley Conference representative will be determined by a league tournament. Austin Peay, the regular-season champ, is a heavy favorite to win. Miami (Ohio) and Central Michigan are in a virtual tie for first in the Mid-American Conference, with Toledo and Northern Illinois just a game behind.

Possible at-large teams are Detroit, Marquette, Notre Dame, an ACC school, and an ECAC tournament winner. MIDWEST

(Four conference champions, four at-large teams)

Arkansas, which ran away with the Southwest Conference title, now must meet the survivor of the league tournament to see who goes to the NCAA playoffs. The Big Eight is in the midst of a league tournament, with Kansas State, the surprise regular-season titlist, favored to win.

The Metro Severn Tournament will be held at Memphis State. Unless another league member pulls off a major shocker, either Louisville or Cincinnati will play in the Midwest, the other most likely in the West Region.

Southern Illinoi and New Mexico State will hold a playoff to determine the Missouri Valley champion. Probable at-large teams will include a Western Athletic Conference school (Arizona or Utah), the Pac Eight runner-up (Oregon or Washington State), and ECAC tournament winner and Creighton. WEST

(Five Conference champions, three at-large teams)

This looms as the best of the regions. No. 1-ranked San Francisco will be undefeated if it beats Notre Dame at South Bend Saturday. The Dons long ago clinched the West Coast Athletic Conference title.

UCLA holds a one-game lead over Oregon in the Pac Eight. The Bruins must beat tailender USC to wrap up yet another NCAA trip. Oregon, however, has to get by Oregon State to avoid ending in a tie with Washington State for second place.

Utah and Arizona, both 9-3 in the WAC, each have one game left. Utah plays at Brigham Young while Arizona travels to Arizona State. If they stay tied, a playoff will be held.

A league tournament will determine the Pacific Coast Athletic Conference champion. Long Beach State and San Diego State tied for the regular season title. Idaho State is the odds-on favorite to win the Big Sky tournament.

Possible at-large teams include Nevada-Las Vegas, Cincinnati or Louisville and a Big Eight School (Oklahoma or Missouri).