Iraqi forces tightened their hold on the fringes of this important port city today and intensified their attacks on Abadan, the refinery center immediately to the east, in an effort to take effective control of Iranian territory on the waterway opening into the Persian Gulf.

While tenacious Revolutionary Guard forces continue to hold the center of Khorramshahr for Iran, Iraq's superior manpower and firepower are slowly wearing down the resistance.

So far, however, Iraq has shown little inclination to send its infantry into the center of the city, where casualties almost certainly would be extremely high and politically dangerous.

Instead, Iraq sent warplanes to bomb Abadan today for the first time in nearly a week and directed artillery barrages into Khorramshahr's center from portions of the city it already holds.

Iraq's official radio said today that Khorramshahr's "final fall into the hands of the Iraqi forces will open the way to Iranian territory adjacent to the Shatt-al-Arab waterway, through the vital town of Abadan."

An Iraqi military communique said Iraq's warplanes had destroyed the television station and fuel storage tanks in Abadan. In the early days of the war, Iraqi bombing had set afire much of the Abadan refinery, Iran's largest.

But in Khorramshahr today, the tenacious Iranian forces were still managing to block the Iraqi Army. The fact is that after 16 days of war, of a relentless artillery siege, of tank attacks, air bombings, ground probes and, in the last two days, a new offensive thrust, the Iranian city is holding. The battle of Khorramshahr is still being fought.

Captain Anonymous, the brusque Iraqi Army officer delegated to show the occasional visitor around his country's front lines in Iran, was not open to any doubts today about the extent to which Iraq is in control of this shattered and smoldering port city.

Picking his way through canyons of metal cargo containers in the western edge of the Khorramshahr dockyards, the tall captain, a luxuriant black mustache bristling over his lip, asked rhetorically: "You don't see any Iranians here, do you? Can you doubt any longer that Khorramshahr is ours?" i

As he spoke, a battery of Iraqi Army 130mm guns opened up with a startling series of sharp bangs, arching shells toward the city center from positions in the thick date palm grove just across the narrow waterway from here. To the rear, up the left bank of the waterway where the main Iraqi positions still are, there was another artillery salvo.

Just on the other side of the 10-foot-tall brick fence that separates the dockyards from a palm plantation, a heavy .50 caliber machinegun was stitching the air between the halting and sporadic pop-pop of semiautomatic rifle fire.

Where the captain stood, between scattered stacks of cargo, no Iranian Revolutionary Guards were to be seen.

Here, at least, on this corner of the dockyards, on the far western edge of the city, which lay somewhere beyond the brick wall, where columns of black smoke were rising and the earth was shaking, the Iraqi Army indeed was in control -- if just barely so.

But the crackling of gunfire not more than 500 yards away in the palm trees belied the repeated claims by officers and soldiers here that the city was really under Iraqi control.

The Iraqi Army squats menacingly on the dusty flat plain that leaves here from Basra, the Iraqi port at the head of the shipping waterway. The Army's numbers are in the tens of thousands, equipped with hundreds of artillery pieces, antiaircraft guns, rockets, tanks and modern tracked bridging equipment, in anticipation of the moment they move forward, over the Karun River, beyond Khorramshahr, to the burning oil complex of Abadan.

This vast, Soviet-trained and equipped force, however, has only just barely lapped the western edges of the city it has been besieging since the third day of the war.

Although the Iraqis claim to have taken the dockyards, along the banks of the Shatt-al-Arab, they only hold a western corner of them.

The rest of the dock area is a desolate no-man's-land where Iranian snipers fire from the steel-plated superstructures of ocean freighters, trapped at the wharf by the war and where tanks, at night exchange fire across the asphalted cargo yards that still separate the Iraqi and Iranian forces in the dock area.

An Iraqi lieutenant, lounging near the dockyard gate, spoke of "pockets of resistance" and snipers in the city, which, aside from its armed human combatants, has been abandoned by its former population of 350,000 except for braying donkeys and roving packs of dogs.

The officers spoke of some 300 to 400 fervent Revolutionary Guards, making a suicidal stand in the rubble-strewn city. But they are not alone, having been reinforced in the past 10 days by Iranian Army commandos and armored troops whose British-made Chieftain tanks still guard the strategic bridge over the Karun River, which the Iraqis will have to cross if they are to move toward Abadan.

With their superior manpower and firepower outside Khorramshahr, time is clearly on the Iraqi's side.It is hard to imagine that they could not win the city if they ever really committed themselves to a close quarters assault, fighting house-to-house to the Kuran River east of the city. That, at least, would give them a chance to move up their modern, tracked river-bridging vehicles, which today were being masked in the palm groves just west of the border to the northwest.

There is little doubt that Iranian resistance is slowly being worn down. The rate of their artillery fire against the Iraqis has fallen off appreciably in the past couple of days, indicating that they may be running short of ammunition.

Their Phantom jets, which in the first 10 days of the war seemed to wander where they wanted, picking off Iraqi military positions, have suddenly become a rarity.

That the Iraqis actually managed to capture a corner of the dockyards shows that despite their cautious advance in the periphery of the city, they have made gains, if not as large as they claim.

Tied to the long concrete wharf stood five of the dozen or so foreign freighters that have been trapped in the port since the war began Sept. 22. Three bore the ugly scars of war.

One, the Capriolo out of Naples, had received a direct hit and the fires that followed forced its Italian crew to seek refuge in an adjacent Greek ship. There the two crews have been huddled through the endless days of the war below decks, seeking safety and playing cards.

Miraculously, there were no casualties on any of the ships, though seamen reported being scared to death for much of the time.

Aboard a Chinese freighter, the Yangchun, 49 Chinese crew members reported that they have been reduced to using the oily, dirty waters of the Shatt for drinking water because other supplies have run out, and the Iraqi occupiers of this end of the port only occasionally bring them new supplies. The crew, like on all the ships, keeps below decks for protection from the shells during the day, emerging only in the evening to get a breath of fresh air.

Proof that the war in Khorramshahr is still far from over lies just about 500 yards along the river where Iraqi T55 tanks are drawn up in sandbagged gunposts.

Behind them the Iranian Navy base along the river was burning briskly, sending up a boiling cloud of thick, greasy black smoke over the river.

Looking down at it all, Wang Tan Lung, the captain of the Yanchun, shuddered as a new salvo of artillery opened up less than 400 yards away across the river. "I want peace, not war, he said."