"virtually unabated" is a correct and usable phrase in written English.
You can use it when you want to express the concept of something continuing without much weakening or interruption. For example, "The rains continued virtually unabated throughout the summer."
Officials in Sudan hope to persuade the families of children born out of wedlock to accept and raise them, but the crisis of abandonment continues virtually unabated.
An ancillary slave trade that had developed distressed Europeans, who forgot that their depredations against Africans had continued virtually unabated until the early 19th century, and they prevailed on the khedive to abolish this commerce.
A peace accord completed here almost 19 months ago has never taken hold, with battles raging virtually unabated as the Congolese and their allies, Angola, Namibia and Zimbabwe, confront the rebels and their backers, Rwanda and Uganda.
The gestures seemed clearly intended to facilitate the mission of the American peace envoy, Gen. Anthony C. Zinni, who arrives this week to try to wrench the Israelis and Palestinians apart after the most violent spate in bitter fighting that has continued virtually unabated for 17 months.
In fact, BP announced that they are now actually siphoning 5,000 barrels per day through the riser insertion tool (RIT), and the live video feed shows the flow virtually unabated (the feed is overloaded, so you may not be able to see it until later tonight).
Donald Chen, executive director of Smart Growth America, a nonprofit research coalition in Washington, D.C., says that the overall declines in urban density, loss of open spaces, and increased auto use that accompany sprawl are continuing "virtually unabated".
Yet most continued to operate unabated.
However, exposures from most toxic waste sites continue unabated.
Moreover, stocks that are traditionally sensitive to the economy, like Caterpillar and Goodyear, were trading as if a recession were imminent, even though virtually all the economic numbers show that the boom continues unabated despite four rounds of interest-rate hikes by the Federal Reserve.
A recent study by researchers at Loyola Marymount University and the Massachusetts Institute of Technology concluded that unabated warming would render Persian Gulf cities like Abu Dhabi, Dubai, and Dhahran virtually unlivable in a matter of decades.
This virtually guarantees that the human tragedy of refugees at the U.S. border will continue unabated.
