The Malta Independent 27 April 2024, Saturday
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Despite Minister’s assurance, geologist insists updated geological map ‘tampered with’

Sabrina Zammit Sunday, 19 November 2023, 07:30 Last update: about 6 months ago

Chamber of Geologists president Peter Gatt insisted that Malta’s geological map has been tampered with in the latest 2022 update, despite assurances to the contrary by Finance Minister Clyde Caruana in Parliament.

A few days ago, in two posts on Facebook, Gatt wrote that the area where Miriam Pace died after her Hamrun house collapsed in March 2020 had been marked as being middle globigerina (brown) in 1993. But, in the updated 2022 map, the same area became lower globigerina (yellow).

Asked about the changes on the geological map by PN MP Darren Carabott in Parliament last Wednesday, Minister Caruana said that the latest developed map was drawn up by the British Geological Survey (BGS) using the latest technology.

Caruana highlighted the shift from a 1:25,000 scale in the 1993 map to a more detailed 1:10,000 ratio in the recent version.

"The 2022 map is based on evidence available at the time of the survey, scientific research and more modern geological concepts… (it shows) changes in the placement of borders and geological structures (such as faults) that improve the relationship between geology and topography, and ensure consistency with available evidence, including on-site observations, as well as modern geological mapping practices."

But Gatt is arguing otherwise.

To support his counterclaim, in comments given to The Malta Independent on Sunday, after the minister’s reply, Gatt said that while the new scale ratio of 1:10,000 “confirms that the 2022 map has a much higher resolution than the previous one, instead of showing more detail (as would be expected) it has more omissions and inexplicably omits a large area of middle globigerina extending from the limits of Fleur-de-Lys to Hamrun, shown in the previous 1993 map”.

He said that the Continental Shelf Department did not present any new evidence to support “the erasing of the middle globigerina over such a large area”.

“There is no rational reason for the tampering of the geological map unless someone is benefitting from this tampering,” he said.

“The ‘updated’ map of 2022 also erased middle globigerina from a large adjacent area throughout Santa Venera, extending from the limits of Fleur-de-Lys to Hamrun, around the former house of Miriam Pace, which collapsed during rock excavation,” he said.

He said that tampering could have a long-term effect on public safety. Legal Notice 136 of 2019 obliges the perit (architect and civil engineer) to consult the geological map of Malta prior to excavation. There is a difference between lower globigerina and the much weaker middle globigerina.

Contacted by The Malta Independent on Sunday, the Finance Ministry said that from studies carried out by BGS at the request of the Continental Shelf Department, “successive geological map interpretations of an area can change as new evidence becomes available, geological concepts change and new mapping methods are used”.

The report said that the 2022 map represents the islands’ strata at the ground surface, where the mapped strata are at least one metre thick. In central Malta, the mapped strata include the Lower Globigerina Limestone Member and the Middle Globigerina Limestone Member.

“In the locality identified as Miriam Pace’s former house, the 2022 geological map shows Lower Globigerina Limestone Member to be present. This is consistent with the interpretation shown in the 1993 geological map, that is, Lower Globigerina Limestone Member is also shown at this locality,” the report said.

It added that this area of Malta is urbanised, with infrastructure or housing covering most of the ground, thus limited natural rock exposures were observed during field mapping in this area. Evidence from the surrounding area was used to complete the geological interpretation, “a common and often necessary approach in geological mapping”.

However, Gatt (above) said that the geology of the southern part of the Santa Venera tunnel area is well studied and indisputably proven to have middle globigerina limestone at the surface “clearly seen along the rocks of the road cut leading to the tunnels, showing several metres of this rock (now partly covered by a wall)”.

In its defence, the ministry said that the report commissioned shows that the 2022 geological map is consistent with the limited and sparse evidence that was available to the geologists during the survey, including in the vicinity of Pace’s former home.

“Urbanised areas typically represent areas of greater geological uncertainty. In such areas, targeted site investigation, potentially including drilling and logging of boreholes, may provide additional evidence that allows the geological interpretation to be revised. Due to the interpretative nature of geological maps, they are intended to guide, but not substitute, appropriate site investigation, including local-scale studies,” the report said.

It added that things could be altered in the future if and when additional information may become available (for example, borehole logs that BGS have not previously had access to) that would require a re-interpretation of the geological map in this area.

Gatt also pointed out that the geological map is published online by the Continental Shelf Department, “although this department does not employ geologists and did not consult the Malta Chamber of Geologists during the production of the map”.

However, in his reply in Parliament the minister said that the BGS engaged a total of six foreign geologists and one local for the map update.

 

The role of geologists

Geologists are appointed as court experts in many countries, especially in matters related to rock excavation, ground contamination, forensic geology and quality of building materials, Gatt said, adding that “I believe that Malta remains the exception… Appointing persons who are not geologists may result in disinformation and a disservice to justice”.

Middle globigerina limestone is a problematic rock, especially when excavated, he explained.

The geologist continued that collapses of built structures, next to very shallow excavation in middle globigerina, have already been reported in Mriehel in the past few years.

It should be noted that Legal Notice 136 on avoidance of damage to third party property requires the sampling of rock by coring prior to excavation.

Moreover, he said that the enacted Legal Notice 136 of 2019 had effectively weakened the protection of third parties by removing the requirement of a geological investigation found in the previous Legal Notice 72 of 2013.

The geologist said that a geological investigation is far more comprehensive and detailed (and would require a professional geologist) than rock sampling by cores required by Legal Notice 136 “that could be done by anyone, including persons who know nothing about the rocks of Malta”.

Gatt was also asked whether he believes that the MCG is given the recognition it deserves.

The Malta Chamber of Geologists (MCG) is the national association of geologists, which is registered as a professional organisation in Malta and is a member of European Federation of Geologists along with national associations of geologists representing 28 countries.

However, he said that the MCG has been left out of the newly-established Building and Construction Consultative Council (BCCC) whose members were approved by Planning Minister Stefan Zrinzo Azzopardi.

“The local exclusion of geologists contrasts with what happens elsewhere, such as in Switzerland where our counterparts, the Swiss National Association of Geologists (CHGEOL) represents geologists on the Swiss regulating body for the built environment,” he said.

Gatt said that the Chamber was made aware that plans for the official recognition of so-called “geological architects”, who are not geologists by profession and not members of MCG.

“These ‘geologists’ will not be qualified to do the work of professional geologists and we could expect a worsening of standards of public safety which were already undermined by Legal Notice 136 that removed the requirement of a geological investigation.”

The geologist continued and said that some European countries have long recognised the profession of the geologist represented by their national association of geologists and set up their national Geological Service or Survey, “whereas Malta remains the only country in Europe without a national geological service”.

“This administrative lacuna is denying Malta the expected standards of public safety and the wealth we can get from our natural resources on land and especially from our vast continental shelf,” he said.

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