Progress on horizontal oil wells
Cuba's oil company Cupet is taking on the challenge of drilling horizontal wells from the mainland into territorial waters off the island's northern coast
8 de febrero de 2017 - Taken from Granma
Just about anyone can imagine how difficult it is to drill an oil well. It is an uninterrupted task, with no rest, that requires the careful attention of dozens of experts.
The time required to complete the drilling is estimated in months, and unfortunately, the prolonged effort is not always rewarded with the oil sought. In other words, drilling oil wells is a costly, highly risky endeavor.
Clearly this is not about digging a hole, but rather the implacable struggle to make use of what can be found in the planet's entrails, a procedure which requires advanced technique and significant financial resources.
For engineer Julio Jiménez Vázquez, leading work onsite for the Cuban state oil company Cupet, drilling is no more than a way to communicate with an oilfield below the earth's surface. He asserts that to complete the job as hoped, one must be able to wait patiently, in anticipation of good news.
He notes that the daily cost of such an effort is in the tens of thousands of pesos, depending on the type of well, and that over the course of the work, one must carefully observe operations, paying attention to the most minimal detail and resolving a variety of unforeseen issues.
"The well is later put into production for years, and the information reported is very valuable for future drilling," notes Jiménez, one of the experts designated to discuss the issue.
The level of complexity is greater when a well is horizontal or changes direction, like those recently drilled by the Central Cuban Drilling and Extraction Company (EPEP-C), in the West Varadero area, which are technologically complicated. They begin on the mainland and reach record distances in territorial waters.
Experts agree that the program underway is this part of Matanzas province has provided many lessons for geologists and personnel linked to oil exploration and drilling in the country.
"Before, looking for oil was relatively easy. Wells were vertical, between 1,200 and 2,000 meters deep, with small angles of inclination. This was the way it was until 2000, when seismic studies and exploratory drills revealed that the Varadero field extended in a northwesterly direction, under the seabed."
Jiménez explains that this drove productive development and, from that time on, horizontal wells were drilled in the area around Boca de Camarioca, an extension of the Varadero Field, the most productive of the northern coast between Havana and Matanzas, which provides heavy crude, and where 97% of the country's production of oil and natural gas is concentrate
"The first extended well was the Varadero 1000. A total of nine have now been completed, all with notable levels of production recorded. At this time, we are drilling the Varadero 1008, which will be the longest drilled in Cuba, with a length of eight kilometers, placing our country among the world's elite of long distance, horizontal wells."
He explained that since its beginning on December 18, 2016, all work has been done in accordance with relevant international regulations, and that thus far, drilling has advanced some 1.3 kilometers. He clarified that the job has not been easy, and that the daily rate of progress is below projections made before work began.
"We have not faced any serious problems, but the extremely hard subterranean rock makes daily progress slow, and obliges us to proceed carefully to deal with continual obstacles, such as a change of drill bit," the engineer commented, while pointing out that the region's heterogeneous geological formations make drilling difficult.
To achieve the ambitious goal of drilling these wells, the country has contracted international companies and several highly specialized service providers who handle drilling equipment, directional control, mud logging, electricity, and foundations, to name a few issues.
It is clear that this involves the latest technology, which is very costly and only within the reach of wealthy countries. Required are a group of indispensable techniques to reach oil below the bedrock and address all the details implicit in the drilling process.
For example, in order to drill the Varadero 1000 well, the country was obliged to contract the Chinese state company Great Wall, to construct a 3,000 horsepower tower, since Cupet's equipment did not have the power to drill at a distance of 8,000 meters.
Most impressive, to untrained observers reaching the site where the Varadero 1008 is under construction, is the giant drilling tower.
Several men dressed in red and blue overalls work feverishly to control what is happening unseen, far underground. The entire team is conscious of the real challenge presented by this well, the deepest in Cuba.
One of the men analyzing data in his control booth, installed close to the beautiful beach resort of Varadero, is engineer Elber Smith Armenteros, principal supervisor of the works, who follows the well's progress along with other experts on duty, day and night, in their fully equipped huts.
"We work 12 hour shifts. The supervision group is in my station, from where the entire process is followed, in constant communication with the other areas. Everyday, at 8:00am, we conduct a kind of check-up to make adjustments and discuss possible eventualities."
The "mayor", as everyone calls him, attributes particular importance to the wellbeing of staff members, who are provided adequate working conditions including food and lodging at the work site.
Every uneventful work day is welcomed enthusiastically by all. Specialists like Rolando González, Yampier Rodríguez and Yiriliam Pérez are confident that everything is being done according to expectations and are encouraged by the hope of finding oil.
The day they see the liquid gold they are seeking begin to flow is, however, still far off. A long period of activity awaits them now.
What is required, Julio Jiménez recalls, is continuing the invariable drilling process, and not missing a single detail in the enigmatic figures provided by sensors deep within the earth.
He insists that this strategy of seeking oil beneath the seabed, from the mainland, lowers costs, and has had positive results thus far.
Fortunately, all horizontal wells drilled to date have been good producers. The Varadero 1008 will not be an exception, he said. If fate smiles on the efforts of workers, the EPEP-C will expand its horizons and reinforce its status as one of the leading state enterprises in the country.