EMerald’s role in the project was to accurately characterize the real geological conditions along the planned railway route, with the help of airborne electromagnetic(AEM) surveys, drilling data, machine learning and 3D modelling.
“It is the first time that technology like ours has been used on an infrastructure project in the region, so it is a marquee moment for both RUMO, EMerald and the region”, says Andi A. Pfaffhuber, CEO of EMerald Geomodelling.
AEM surveys and 3D modelling at the forefront
The aim of the project was threefold: to understand large-scale trends in ground conditions; to map different soil and rock types, both in terms of soil type and in terms of mechanical properties; and to optimize upcoming drilling campaigns, with a focus on reducing the number of total drillings required.
Field surveys to acquire AEM data were carried out in December 2021. The AEM surveys covered portions of three different segments of the railway. EMerald then monitored the data collection remotely, ensuring that data quality was sufficient for its detailed, geotechnical applications. A total of 170 km of railway alignment and 730 line-km of flights were covered by these field surveys.
EMerald generated geophysical models – specifically electrical resistivity models – that were then interpreted to generate ground models, before presenting recommendations of areas in need of follow-up ground investigations.
“By using both AEM data and existing data, combined with internal software, we were able to provide RUMO with suggestions of where to focus their follow-up investigations. This proved very valuable for them, and they estimate that it saved them about 33% of the drillings they would otherwise have done”, says Anne Have Rasmussen, Director of Operations at EMerald Geomodelling.
3D volumetric models of different materials were also performed, indicating the certainty of different predictions.
“We were able to give a prediction of the sediment type along the length of the railway sections. This aids, among other things, RUMO in planning their excavation methods”, says Rasmussen.
Weather proves challenging
Flying in Brazil during December, however, is no straightforward task.
“As the AEM data collection occurred during Brazil’s rainy season, flying was challenging due to the heavy rainfall. Furthermore, all gathered data needed to be thoroughly treated before it could be utilized. However, the combination of a skilled team and our extensive project experience made us overcome the challenges we faced”, Rasmussen explains.
Efficient drilling plans allowed for quicker start and less risk
Commenting on the results, Jose Carlos Filho, Executive Manager of Expansion Projects at RUMO, had the following to say:
“The partnership with EMerald was a must to overcome the huge deadline challenges that faced in the project, which is currently the largest project in our portfolio. In addition, this innovative technique of geomodelling brought key values such as the increase of the project’s executive plan capability.”
“By applying EMerald’s technology, the project was able to begin quicker and with less risk. The geological models delivered by EMerald provided us the opportunity to create a more efficient drilling plan, and it also reduced the geological risk overall of the project”, Filho concludes.