Since 2014, Wintershall has held a participation interest in the Aguada Federal block in the Neuquén province and is the operator here. Together with the local state-owned energy company, Gas y Petróleo del Neuquén S.A. (GyP), Wintershall currently investigates the block and will possibly develop it further. The block contains promising oil shale in the Vaca Muerta formation. It is the first shale oil project that Wintershall is conducting as operator.
The exploration and production of unconventional resources poses major technological challenges. Wintershall is in an excellent position to master these challenges, thanks to its many decades of experience in environmentally responsible and efficient production from complex reservoirs, and to its specialist technological expertise in the production of tight gas in Germany.
The target The Vaca Muerta formation
The wells in the Aguada Federal block are targeting the geological Vaca Muerta formation, which extends across the central Argentine province of Neuquén. Vaca Muerta forms one of the largest shale gas and shale oil formations worldwide. At a depth of between 2,700 and 3,000 meters, the formation covers an area of 30,000 square kilometers, which is approximately the size of Belgium. These layers of rock are between 150 and 600 meters thick and have a high organic carbon content. The technical characteristics of the Vaca Muerta shale rock are similar to the shale rock already exploited in the USA.
Aguada Federal The pilot phase
Following a comprehensive analysis of the rock formation with the help of 3D seismic data, two vertical wells were spud during the technology phase in 2015. They are located four kilometers apart. Seven rock cores with a total of length of 121 meters were recovered from the wells. Geologists carefully examined these cores for important properties such as the rock strength and porosity. These wells have provided important information about the properties of the Vaca Muerta formation.
The information obtained from these vertical wells formed the basis for four wells with each of them having a 1,000-meter horizontal section. Within this kilometer, a total of ten fracs have been placed at a distance of approximately 100 meters. Two of the four wells have been drilled to a similar depth, but stimulated differently. This makes it possible to compare, which frac design works better and which part of the Vaca Muerta formations shows higher production in order to optimize the later development.
Wintershall is working closely with the contractors in order to carefully monitor the entire process.
Road to development
In the Neuquén Basin, Wintershall drilled initial wells in the Aguada Federal block to more closely investigate the potential provided by the Vaca Muerta Formation.
Vaca Muerta formationThe Vaca Muerta formation holds one of the world’s largest shale oil and gas resources.
20 years experienceWintershall has been investigating and getting to know the region and geology for the last 20 years.
Being operator in two blocksWintershall carries out shale oil projects as operator at the Aguada Federal and Bandurria Norte blocks.
Bound by tradition High environmental and safety standards are a matter of course
The exploration and production of unconventional reservoirs pose considerable technological challenges. Wintershall is ideally positioned to meet these challenges thanks to its decades of experience in efficient production from complex reservoirs and its unique technological expertise garnered from its tight gas production in Germany.
Wintershall is always commited to complying with international conventions, local laws and regulations, as well as its own high standards that it has set itself with regard to protecting people and the environment. The following principle applies to all its activities: health, safety and environment shall always be given priority over economic success.
Wintershall has been working in Argentina for almost four decades and has established a strong bond with the country. For Wintershall, close ties and good cooperation between industry, policymakers and the public are important for recovering the available energy resources in a sustainable manner.
Wintershall is also engaged in social and cultural projects in the Argentine regions where it works, and supports there numerous local health, education and cultural projects. Wintershall therefore takes responsibility as a reliable partner.
Handling water in a responsible manner
Handling natural resources in a responsible manner, for instance the careful use and protection of water, is a matter of course for Wintershall. The company has set itself the goal of keeping water consumption as low as possible and also to minimize the impact on the environment. Hence, water management that saves resources and the protection of the environment are part of the company’s project planning from the very outset. An environmental impact assessment is carried out by external parties for each project. This assessment also forms the basis for the project authorization by the relevant authorities.
Wintershall aims, even during the pilot phase, to save or reuse as much water as possible, thanks to innovative technologies or by recycling drilling fluids. This way the volume of water used can be reduced with each well. Then, at the end of the drilling campaign, the water is treated and disposed of properly. The consumption and disposal of the water is regulated and monitored by provincial authorities.
When the projects enter the development phase the implementation of a comprehensive water management concept is planned. For example, in the production facilities in Aguada Pichana and San Roque, in which Wintershall holds stake, there are dedicated wells to extract deep formation water (no fresh water). Production water is treated in a processing plant and thereafter reinjected to the formation.
Wintershall is currently discussing with neighboring license holders to develop a common water management strategy.
Harnessing the considerable potential provided by unconventional resources
Argentina has potential: alongside the USA, Argentina is one of the most important growth regions in the field of unconventional oil and gas production. The South American country has the second-largest shale gas resources and the fourth-largest shale oil resources in the world.
According to the U.S. Energy Information Administration (EIA), there are 23 trillion cubic meters of shale gas in Argentina, which equals 11 percent of the global shale gas resources. Argentina also has the fourth-largest shale oil resources worldwide with 27 billion barrels of oil equivalent. Shale oil and shale gas are embedded in the rock where they were formed.
In contrast to conventional and tight gas reserves they were not able to migrate to higher and more permeable rock strata. That is why horizontal wells and hydraulic stimulation (hydraulic fracturing) are necessary to extract this oil and gas. So far, around 700 shale wells in the entire Vaca Muerta region have been drilled.