A fissure in a rock formation towering above Popeye Village's Anchor Bay has existed for hundreds of years and does not threaten the picturesque site, geologists have said.

A grainy photo with the fissure circled in red prompted cries of alarm on social media, with users wondering if the rocks were at an imminent risk of collapse. 

"Is Popeye Village safe? Are we risking a natural disaster at no time at all?" asked a Facebook user who shared the post.  

Concern quickly spread, with many people drawing comparisons with the recent collapse of a somewhat more famous rock formation.

"What happened to the Azure Window could happen here," one layman warned.

Geologists allay fears

But historic photos dating back at least two decades show that the fissure has long existed, and expert geologists told Times of Malta that there is little cause for alarm. 

"The plateau fracture [highlighted in the social media post] was already charted in topographical maps of the beginning of the 20th century," University of Modena and Reggio Emilia geomorphologist Mauro Soldati told Times of Malta, "and it is likely that it dates back to hundreds of years ago, if not millenia." 

The fissure can be seen in this aerial photo taken in 1998... Photo: PA

Prof. Soldati leads an expert team who, in collaboration with the University of Malta, carry out extensive monitoring of various sites across Malta's north-west coast, with the aim of providing scientific data for authorities to identify and manage risk areas. 

Their work includes GPS monitoring of the Anchor Bay area highlighted by alarmed social media users. 

Aerial imagery

Those unconvinced by Prof. Soldati's assurances can also take comfort in photographic proof that the fissure is not a recent phenomenon. 

An aerial photo dating back to 1998 clearly shows the fissure, and comparing it to a more recent one from 2016 shows that the cleaved rock has not shifted over the past two decades. 

Both images were sourced from the Planning Authority's GeoServer database. 

The fissure is also clearly visible in several online photos of Popeye Village, which started off as a film set in 1980 and has now become a tourist attraction in its own right. 

...as well as in this similar shot taken two years ago in 2016. Photo: PA

Rock formations

Malta's north-west coast is characterised by what geographers term "lateral spreading", with brittle upper coralline limestone sitting atop softer blue clay. While the former creates a sharp, steep scarp face, blue clay leads to more gentle slopes which often stretch down to sea level.

In his comments, Prof. Soldati emphasised the geomorphological differences between rocks Anchor Bay at the Azure Window formation which disappeared into the sea last March.

The two, Prof. Soldati said, were "not comparable". 

The Azure Window protruded into the sea and had no natural buffer to withstand direct impacts, with its "steep rectilinear morphology" making it further susceptible to collapse. 

Anchor Bay, on the other hand, was shaped by landslide activity rather than pounding waves. Its plateau has been joined and faulted by tectonic activity and chemical weathering - caused by rain water reacting with minerals in rocks - having widened joints and allowing rainwater to seep in deeper. 

Scientists from the University of Modena and Reggio Emilia working with others from the University of Exeter have found that the main cliff slope above Popeye Village was formed around 21,000 years BP [Before Present], with movement occurring when sea levels were an estimated 130 metres below their present level.