Gyrocopter zooms in on Karoo
Crucial study of Karoo rock structure gets off the ground
THIS week a gyrocopter will start flying over the Eastern Cape part of the Karoo, carrying an instrument that will survey the rock to a depth of a kilometre.
The geophysics research is critical to any decision about shale gas development.
“For the first time in this part of the Karoo, we will be measuring the magnetism of the rocks to determine if there are deep fault lines, fractures and magnetically mineralised rock bodies, from a few hundred metres down to a kilometre,” says geophysics professor Moctar Doucouré.
He is a member of the Africa Earth Observatory Network (AEON) of the Earth Stewardship Science Research Institute at Nelson Mandela Metropolitan University in Port Elizabeth.
The gyrocopter will be flying 40m above the ground along a 10 000km survey line straddling the districts of Jansenville, Klipplaat and Waterford.
It has taken many months to get the project airborne because every landowner and community in the survey area has needed to give consent.
This has required the building of trust and ensuring landowners feel comfortable about why the data is needed and for whom.
The survey land is within the area the network has been researching for three years.
“It is one thing to create big projections in terms of gross domestic product, but what does this mean for the environment, the people on the ground and the existing agricultural economy?
“There are so many factors that need to be considered.
“We need to know, for example, whether there are deep faults and fractures, as they would be a conduit for gas and contaminants from fracking or deep drilling.
“This could also precipitate micro earthquakes.”
Doucouré says a key starting point is “to establish a natural baseline of how the Karoo looks today – the surface and the subsurface – so that if shale gas exploration and/or fracking ever take place, we will be able to see exactly what has changed”.
Since 2013, the researchers’ focus has been the Karoo’s shale gas baseline.
The team of professors and 30 Master’s and PhD students are co-ordinating several baseline studies in the Karoo – from groundwater data to livelihoods to deep rock structure to community health to ecosystem health – to develop the first comprehensive portrait of the Karoo.
“We have done measurements of the electrical conductivity and microseismicity down to 5km depths.
“We need to put all this data together to better understand the interplay between the fracture zones and sedimentary rocks, in particular the hard mudstones of the Whitehill Formation, which is known to be a potential source of shale gas at depth.”
The professor says it is too early to comment, but the team is starting to gather key data, including information about the quality of water and the levels of salinity in deep level rock formations.
The research network and institute provide postgraduate student development through mentorship and research.
Thirty-two of the university’s postgraduate students are connected to the institute across faculties, including the arts, health sciences and business and economic sciences.
The Eastern Cape government has contributed R16 million to the research programme, while the university has provided R15m through the network and institute, predominantly by supporting postgraduate students and research capacity.
One of the team’s key engagements in the Karoo has been to explain to landowners and communities why this is “real” research.
Since 2011, the Karoo’s citizens have heard representatives of oil and gas companies claiming to have carried out in-depth research that has included studies of the Karoo’s groundwater.
The companies’ water studies were little more than desktop exercises, based on which they felt justified to make statements about the safety of the water and environment in their hands.
Groundwater is the main source of water in the Karoo and if shale gas mining were to go ahead, a vast amount of water would be required.
Farmers and communities in the Karoo access groundwater down to a depth of about 150m, but the same groundwater source may lie as deep as 500m in places.
“It is critical to research and analyse properly the Karoo’s groundwater as it is today, with the host structures in the surface and subsurface. This requires years of applied hydrogeology, geophysics, geochemistry and ecosystems research,” says Doucouré.
He is pleased that since 2014 they have made significant progress with groundwater sampling.
“To date our postgraduate students have sampled more than 700 boreholes across the Eastern Cape part of the Karoo.
“The samples are analysed for their chemistry in our (university) laboratory by expert technicians. This includes analysing biogenic methane levels, which are very different from the thermogenic methane at deep levels associated with fracking.”
Doucouré says baseline studies are all about creating a foundation of thorough research from which to think and act.
“You cannot take decisions or produce accurate economic forecasts until you have collected and analysed the required data. Only then can you create a clearer picture of the resource, in this case, shale gas, and the environment where it exists,” the professor says.
The same applies to any other form of mining, including uranium, for which the Karoo is also being targeted.
To assist the people of the Karoo to better understand the researchers’ work, the team has arranged meetings and round-table discussions with communities, local and district municipalities, and agricultural bodies such as Agri Eastern Cape, Agri SA and the National Wool Growers’ Association.
They have also led an educational focus initiative in Cradock, where they demonstrated a “mock fracking” in a sandbox, using colourants to show how fracking water flows through the sand.
“Citizen science is a big part of our approach and we are training 10 women from Cradock to do water sampling and monitoring.
“They will be able to take readings of basic water measurements, like salinity, temperature and levels in the boreholes, and send them to our university laboratory in Port Elizabeth using smartphones.
“This will assist us in flagging problems.”
Doucouré says this training is to be extended to other municipalities.
The team has chosen to start this in Cradock because it is demarcated
You cannot take decisions until you have data
in most of the exploration licensing application areas.
The team has been using a drone to survey the area from Tarkastad to Cradock, Graaff-Reinet and Aberdeen.
The drone is capable of carrying 5kg of photographic and video equipment to monitor the surface and ecosystem of the Karoo.
It will also use hyperspectral remote sensing instruments to measure plant and soil conditions.
“We are also collecting samples of living Karoo micro invertebrates, which are sensitive to changes in the environment,” Doucouré says.
This work is being done in collaboration with the Chair of Shallow Water Ecosystems at the university.
A postgraduate student in the department of botany is testing the effects of fracking fluid on Karoo plant species that are of conservation concern.
This work is being done in a lab- oratory, but is also to be carried out on a larger scale where the plants are growing in the Karoo.
The findings of all these and other research initiatives are to be holistically analysed and assessed by the team.
They are also to be made available to everyone.
“We are getting close to being able to release some interesting finds, hopefully before the end of the year,” says Doucouré.