The world's newest lava lake appeared in Africa for the first time in 75 years.

Described as a "very small, bubbling lava lake," by Benoit Smets, a volcanologist at the European Center for Geodynamics and Seismology in Luxembourg in an interview with Live Science, "It disappears and reappears, but if the current activity continues, we will probably have a lava lake like we have at [neighboring volcano] Nyiragongo within a few years to decades." 

Scientists believe this lava lake could be here to stay permanently, but it's unclear when the flood first formed at the bottom of a 1,650-foot-deep crater.

Sulfur dioxide gas levels never dropped off after the Nyiragongo volcano's 2011-2012 eruption ended, which raised concerns from Robin Campion, a volcanologist at the Universidad Nacional Autonoma de Mexico in Mexico City.

"I noticed something was very strange, because I was constantly seeing that [sulfur dioxide] was quite high," Campion told Live Science. "Only the formation of a lava lake could explain these high values." 

Smets argues that the lava lake didn't actually start to form until much more recently.

A group of scientists, including Smets, were at the volcano in early July and saw fire fountains spurting from the crater-- but no lava lake, reported Live Science. 

Campion calls those spurts the "foundation" of the lake. 

The lake was anticipated since the 2012 eruption of Nyiragongo. Now that the lake is here, it's putting nearby civilians in danger. The threatened towns include Sake and Goma. 

The lava lake threatens civilians with acid rain from its volcanic gas, which corrodes roofs, destroys crops and affects human health, according to Live Science. 

The findings of the lava lake were published Nov. 7 in the journal Geophysical Research Letters.