Large and massive warehouses and tanks, lighting towers and metal structures at night, oil factories and laboratories in the Kingdom of Saudi Arabia, the concept of petroleum engineering in the Gulf countries, oil and gas refineries, petrochemical industries and projects, the renaissance of the Saudi national economy
The concept of extracting and exporting underground resources, quality of tools and equipment for the manufacture and storage of petroleum, an oil platform for extracting oil, a close-up of a drilling rig drilling for oil in the middle of the sea, huge drilling machines
Drilling and prospecting for underground resources in the Kingdom of Saudi Arabia, petrochemical industries and projects in the Kingdom, pipelines and heavy steel equipment, huge drilling machines used in extracting petroleum, development of the Saudi economy, work in the field of industrial and petroleum engineering.
Oil production and refining plants and factories, engineering, equipment and huge industrial warehouses, close-up of oil and gas refining plant, petrochemical industrial projects, economic growth and progress, oil production in the Kingdom of Saudi Arabia
Lighting of towers and metal structures at night, large and huge warehouses and tanks, oil factories and plants in the Kingdom of Saudi Arabia, the concept of petroleum engineering in the Gulf countries, oil and gas refinery, petrochemical industries and projects, the renaissance of the Saudi national economy
Factories and laboratories of the Kingdom of Saudi Arabia in Al-Shorouk, oil and gas refining plant, Dukhan refinery, laboratories, petrochemical industries and projects, huge and large warehouses, engineering and industrial equipment.
The concept of petroleum engineering, oil and gas refinery, petrochemical industries and projects, the renaissance of the Saudi national economy, oil factories in the Kingdom of Saudi Arabia, the quality of machinery and equipment in factories that extract oil wealth from the depths of the sea
Large and huge warehouse tanks, metal towers and structures in desert lands, oil and gas refineries, petrochemical industries and projects, the concept of petroleum engineering in the Gulf countries, the renaissance of the Saudi national economy, fuel factories in the Kingdom of Saudi Arabia
Adoption of modern techniques and technology in gas production in the Kingdom of Saudi Arabia, quality of oil production laboratories and equipment, cartoon drawings of a Saudi-Gulf Arab engineer wearing a protective helmet working on an oil refinery, following up on the progress of factory work, Saudi professions and jobs
Monitoring the progress of work in factories, the concept of gas productivity in the Kingdom of Saudi Arabia, Saudi jobs and professions, a close-up photo from the back of a Saudi Gulf Arab engineer wearing a helmet and a protective vest standing between pipelines at sunset, the background of an oil refining factory
Petrochemical industries and projects, working in petroleum engineering, close-up from the back of a Gulf engineer wearing a protective suit and helmet assessing the quality of oil plants in Saudi Arabia, oil and gas refining plant in the industrial area
Quality of oil production plants and equipment, economic growth and progress, petrochemical industrial projects, monitoring the progress of factory work, cartoon drawings of a Saudi Gulf Arab engineer wearing a safety helmet, adopting modern techniques and technology in gas production in the Kingdom of Saudi Arabia
Metal and chemical industries, oil factories in Saudi Arabia, quality of petroleum production plants and equipment, large industrial facilities, oil and gas refinery, petrochemical projects contributing to the renaissance of the Saudi national economy
Renaissance of the Saudi national economy, oil factories and laboratories in the Kingdom of Saudi Arabia, oil and gas refineries, the concept of petroleum engineering in the Gulf countries, large and huge warehouses and tanks, petrochemical industries and projects
The concept of petroleum engineering in the Gulf countries, oil and gas refineries, petrochemical industries and projects, the renaissance of the Saudi national economy, the view of large and huge warehouses and tanks at sunset, oil factories and laboratories in the Kingdom of Saudi Arabia
Renaissance of the Saudi national economy, the concept of petroleum engineering in the Gulf countries, metal towers and structures in the desert, oil and gas refineries in the Kingdom of Saudi Arabia, large and huge warehouses and tanks, petrochemical industries and projects.
The concept of petroleum engineering in the Gulf countries, the renaissance of the Saudi national economy, oil and gas refineries, petrochemical industries and projects, towers and metal structures in desert lands.
Steel pipelines and cables, monitoring the progress of work in factories and plants, close-up from the back of a Saudi Arabian Gulf engineer working in an oil and gas refinery, working in the field of petrochemical industries and projects, the concept of gas productivity in the Kingdom of Saudi Arabia
Saudi jobs and professions, monitoring the progress of work in factories, close-up photo from the back of a Saudi Arabian Gulf engineer wearing a traditional thobe and shemagh standing between pipelines at sunset, the concept of gas production in the Kingdom of Saudi Arabia, background of an oil refinery
Quality of oil production plants and equipment, Use of modern techniques and technology in gas production in Saudi Arabia, Close-up of a Gulf Arab man wearing a helmet and a protective jacket holding a tablet in his hand and following the progress of the factory, Youth professions and jobs, Oil refinery background
Factories and laboratories in the Kingdom of Saudi Arabia, Nahar oil and gas refining plant, Dukhan refinery laboratories, petrochemical industries and projects, huge and large warehouses, engineering and industrial equipment.
Follow up the progress of work in factories and plants, a group of Saudi Arabian Gulf engineers working in an oil and gas refining plant, working in the field of petrochemical industries and projects, steel pipelines and cables, the concept of gas productivity in the Kingdom of Saudi Arabia
Follow up the progress of work in factories and plants, a group of Saudi Arabian Gulf engineers working in an oil and gas refining plant, working in the field of petrochemical industries and projects, steel pipelines and cables, the concept of gas productivity in the Kingdom of Saudi Arabia
Modern techniques and technology in oil and gas production in the Kingdom of Saudi Arabia. Rear view of a Saudi businessman wearing a thobe, helmet and headband watching the progress of factory work, large buildings with many pipes and steam rising in the sunlight, blue sky with clouds, Saudi professions and jobs in the background of an oil refinery
The concept of gas production in the Kingdom of Saudi Arabia, Saudi professions and jobs, following up on the progress of work in factories, a picture from the back of two Saudi Arab Gulf engineers wearing helmets and protective vests standing between pipelines at sunset, background of the oil refining plant
Oil storage areas in the Kingdom of Saudi Arabia, petrochemical projects contributing to the renaissance of the Saudi national economy, metal and chemical industries in desert areas, a picture of oil and fuel storage, huge industrial facilities, the quality of laboratories and equipment for the production of underground resources
Saudi jobs and professions, following up on the progress of work in factories, a close-up photo from the back of a Saudi Gulf Arab engineer wearing a helmet and a protective vest standing between pipelines at sunset, the concept of gas productivity in the Kingdom of Saudi Arabia, background of an oil refining plant
Adopting modern technologies in gas production in Saudi Arabia, following up on the progress of work in factories, the interior of a large industrial building equipped with pipes, heavy equipment and tools, the concept of engineering and industry
Industrial engineering and equipment, petrochemical industries and projects, steel pipelines and cables, oil and gas refining plant in the industrial area, large and huge warehouses, factories and plants in the Kingdom of Saudi Arabia
Working in the industrial engineering sector, a close-up photo of a Saudi Gulf Arab engineer wearing a jacket and a protective helmet standing with crossed hands at his workplace, Saudi laboratories and factories, youth engineering professions and works, standing confidently and looking at the camera
Fuel factories and mines in Saudi Arabia, large and huge warehouses and tanks, towers and metal structures in desert lands, oil and gas refineries, petrochemical industries and projects, the concept of petroleum engineering in the Gulf countries, the renaissance of the Saudi national economy
Following up on the progress of work in factories, the concept of gas production in the Kingdom of Saudi Arabia, Saudi professions and jobs, a picture from the back of engineers, a picture from the back of a Saudi-Gulf Arab businessman wearing the traditional Saudi thobe standing in a desert area at sunset, the background of an oil refinery factory
Follow up the progress of work in factories, the concept of gas production in the Kingdom of Saudi Arabia, a picture from the back of a Saudi Arabian Gulf man wearing traditional dress and a shemagh standing in an oil and gas refining plant, working in the field of petrochemical industries and projects, steel pipelines and cables
Following the progress of work in factories, a close-up photo from the back of a Saudi Gulf Arab engineer wearing a helmet and a protective vest standing between pipelines at sunset, the concept of gas production in the Kingdom of Saudi Arabia, Saudi professions and jobs, background of an oil refining factory
Oil refineries in Saudi Arabia, the concept of work in the industrial engineering sector, the quality of machinery and equipment in oil extraction plants, modern technologies in the production of oils and gas
Oil refineries in Saudi Arabia, quality of machinery and equipment in oil extraction plants, use of modern technologies in oil and gas production, concept of work in the industrial engineering sector
Pipelines and steel cables, Petrochemical industries and projects, Oil and gas refinery in the industrial area, Factories and plants in the Kingdom of Saudi Arabia, Industrial engineering and equipment, Huge and large warehouses, View of smoke from large industrial facilities at sunset
Huge and large warehouses, petrochemical industries and projects, steel pipelines and cables, a large oil refinery equipped with complex machines in a vast desert landscape and distant mountains, factories and plants in Saudi Arabia, oil and gas refining plant in the industrial area
Saudi Vision 2030, Integrating Technology with Work, Developing the Saudi Economy, Quality of Petroleum Extraction Tools and Equipment, Selling and Exporting Subsoil Resources, Oil and Gas Exploration Machines, Electronic Screen with Statistical Symbols and Graphics, Rising Stock Market Shares
Lighting of towers and metal structures, gas refinery, cloudy sky, oil factories and plants in Saudi Arabia, petroleum engineering concept in the Gulf countries, petrochemical industries and projects, large and huge warehouses and tanks
Oil and gas refineries, towers and metal structures in desert lands, fuel factories and mines in Saudi Arabia, large and huge warehouses and tanks, petrochemical industries and projects, the concept of petroleum engineering in the Gulf countries, the renaissance of the Saudi national economy
Petrochemical industries and projects, oil and gas refinery, concept of petroleum engineering in the Gulf countries, renaissance of the Saudi national economy, lighting towers and metal structures in the evening, large and huge warehouses and tanks, oil factories and plants in the Kingdom of Saudi Arabia
Huge and large warehouses, petrochemical industries and projects, engineering and industrial equipment, factories and laboratories in the Kingdom of Saudi Arabia, oil and gas refining plant in the middle of the sea, Dukhan refinery laboratories.
Oil factories and plants in the Kingdom of Saudi Arabia, petrochemical projects contributing to the renaissance of the Saudi national economy, oil and gas refinery, the concept of petroleum engineering in the Gulf States, lighting towers and metal structures at sunset, large and huge warehouses and tanks
Oil and gas refinery in industrial area, factories and plants in Saudi Arabia, huge and large warehouses, industrial engineering and equipment, petrochemical industries and projects, steel pipelines and cables
The concept of petroleum engineering in the Gulf countries, lighting towers and metal structures at sunset, large and huge warehouses and tanks in desert areas, petrochemical projects contributing to the renaissance of the Saudi national economy, oil factories and plants in the Kingdom of Saudi Arabia, gas refinery
Achieving the industrial revolution, Saudi laboratories and factories, working in the industrial engineering sector, a close-up photo of a Saudi Gulf Arab engineer wearing a jacket and a protective helmet standing with crossed hands at his workplace, youth engineering professions and works, standing confidently and looking at the camera
Renaissance of the Saudi national economy, oil factories and laboratories in the Kingdom of Saudi Arabia, oil and gas refineries, the concept of petroleum engineering in the Gulf countries, lighting towers and metal structures at sunset, large and huge warehouses and tanks, petrochemical industries and projects
Petrochemical industries and projects, work in the field of petroleum engineering, a picture from the back of a Gulf engineer wearing a protective suit and a protective helmet evaluating the quality of oil factories in the Kingdom of Saudi Arabia, an oil and gas refining factory in the industrial zone,
Oil refinery, petrochemical industries and projects, renaissance of the Saudi national economy, large and huge warehouses and tanks, lighting of metal structures, factories and plants in the Kingdom of Saudi Arabia, the concept of petroleum engineering in the Gulf countries
Engineering and urban development of oil refineries in the Kingdom of Saudi Arabia, oil refinery on soft golden sands, harsh and dry climate, adoption of modern techniques and technology in oil and gas production, petrochemical industries and projects, huge and modern tools and equipment
Oil and gas refinery in industrial area, factories and plants in Saudi Arabia, huge and large warehouses, industrial engineering and equipment, petrochemical industries and projects, steel pipelines and cables
Oil factories and laboratories in the Kingdom of Saudi Arabia, oil and gas refineries, renaissance of the Saudi national economy, lighting towers and metal structures at night, the concept of petroleum engineering in the Gulf countries, large and huge warehouses and tanks, petrochemical industries and projects
Adopting modern technologies in gas production in Saudi Arabia, following up on the progress of work in factories, the interior of a large industrial building equipped with pipes, heavy equipment and tools, the concept of engineering and industry
Oil and oil extraction, underground resources in the Kingdom of Saudi Arabia, quality of oil extraction tools and equipment, silhouette of an excavator exploring for oil in the desert at sunset, Salwit
Fuel factories and mines in Saudi Arabia, large and huge warehouses and tanks, towers and metal structures in desert lands, oil and gas refineries, petrochemical industries and projects, the concept of petroleum engineering in the Gulf countries, the renaissance of the Saudi national economy
Petrochemical industries and projects, work in the field of petroleum engineering, a close-up photo of a Gulf engineer wearing a protective suit and a protective helmet evaluating the quality of oil factories in the Kingdom of Saudi Arabia, an oil and gas refining plant in the industrial zone
Engineering professions and jobs, monitoring the progress of factory work, cartoon drawings of a Saudi Gulf Arab engineer wearing a protective helmet, adopting modern techniques and technology in gas production in the Kingdom of Saudi Arabia, quality of oil production plants and equipment, petrochemical industrial projects
Steel pipelines and cables, gas productivity concept in Saudi Arabia, monitoring the progress of work in factories and plants, a group of Saudi Arabian Gulf engineers working in an oil and gas refining plant, working in the field of petrochemical industries and projects
Adoption of modern techniques and technology in oil and gas production in the Kingdom of Saudi Arabia, quality of production plants and equipment, platforms for extracting oil and oils in the middle of desert lands, extraction and export of underground resources at sunset
Fuel factories and mines in Saudi Arabia, large and huge warehouses and tanks, towers and metal structures in desert lands, oil and gas refineries, petrochemical industries and projects, the concept of petroleum engineering in the Gulf countries, the renaissance of the Saudi national economy
Steel Pipelines and Cables, Huge and Large Warehouses, Petrochemical Industries and Projects, Large Oil Refinery with Complex Machinery, Factories and Plants in Saudi Arabia, Oil and Gas Refining Plant in Industrial Area
Renaissance of the Saudi national economy, the concept of petroleum engineering in the Gulf countries, towers and metal structures in the desert, oil and gas refinery in the Kingdom of Saudi Arabia, large and huge warehouses and tanks, petrochemical industries and projects
Oil and gas refinery, lighting towers and metal structures, oil factories and plants in the Kingdom of Saudi Arabia, the concept of petroleum engineering in the Gulf countries, petrochemical industries and projects, the renaissance of the Saudi national economy, large and huge warehouses and tanks
Use of modern techniques and technology in gas production in Saudi Arabia, quality of oil production plants and equipment, back view of a Saudi Arabian Gulf man wearing a helmet and a protective vest following the progress of factory work, Saudi professions and jobs, oil refinery background
Fuel factories in the Kingdom of Saudi Arabia, large and huge warehouses and tanks, towers and metal structures in desert lands, oil and gas refineries, petrochemical industries and projects, the concept of petroleum engineering in the Gulf countries, the renaissance of the Saudi national economy
Giant industrial engineering and equipment, oil and gas refinery in industrial area, steel pipelines and cables, petrochemical industries and projects, large industrial complex with tall smoke chimneys in Saudi Arabia, huge and large warehouses
Extracting underground resources from the sea, huge machines and heavy equipment used in petroleum exploration, work in the field of petroleum engineering, petrochemical industries and projects in the Kingdom, oil and gas refining factories in the industrial zone in Saudi Arabia, Saudi economic growth and progress
Economic growth and progress, petrochemical industrial projects, monitoring the progress of factory work, cartoon drawings of a Saudi Gulf Arab engineer wearing a safety helmet, adopting modern techniques and technology in gas production in the Kingdom of Saudi Arabia, quality of oil production plants and equipment.
Quality of oil production plants and equipment, petrochemical industrial projects, economic growth and progress, adoption of modern techniques and technology in gas production in the Kingdom of Saudi Arabia, cartoon drawings of an oil refinery in the desert
The concept of work in the industrial engineering sector, the quality of machines and equipment in oil extraction laboratories, modern technologies in oil and gas production, petroleum refining plants in the Kingdom of Saudi Arabia.
Huge machinery and heavy equipment used in petroleum exploration, work in the field of petroleum engineering, oil and gas refining plants in the industrial zone in Saudi Arabia, extracting underground resources from the sea, petrochemical industries and projects in the Kingdom, Saudi economic growth and progress
Huge and large warehouses, petrochemical industries and projects, steel pipelines and cables, a large oil refinery equipped with complex machines in a vast desert landscape and distant mountains, factories and plants in Saudi Arabia, oil and gas refining plant in the industrial area
The concept of gas productivity in Saudi Arabia Monitoring the workflow in factories, pipelines and steel cables, a close-up shot of a group of Saudi Gulf engineers working in an oil and gas refining plant, working in the field of petrochemical industries and projects
Engineering development of oil refineries in Saudi Arabia, oil mines on soft golden sands, harsh and dry climate, adoption of modern technologies in oil and gas production, petrochemical industries and projects, huge and modern tools and equipment, towers and metal structures in desert lands
Large and massive warehouses and tanks, lighting of towers and metal structures at sunset, the concept of petroleum engineering in the Gulf countries, oil and gas refinery, petrochemical industries and projects, the renaissance of the Saudi national economy, oil factories and plants in the Kingdom of Saudi Arabia
Oil and gas refineries, petrochemical industries and projects, the concept of petroleum engineering in the Gulf countries, the renaissance of the Saudi national economy, fuel factories and mines in the Kingdom of Saudi Arabia, large and huge warehouses and tanks, towers and metal structures in desert lands
The quality of machinery and equipment in oil extraction plants, a picture showing a Saudi Arabian Gulf man in a transparent way at sunset and behind him are oil refinery factories in the Kingdom of Saudi Arabia, the use of modern technologies in the production of oils and gas, the concept of work in the industrial engineering sector, a view of clouds in the sky
Renaissance of the Saudi national economy, large and huge warehouses and tanks, factories and plants in the Kingdom of Saudi Arabia, the concept of petroleum engineering in the Arab Gulf countries, oil and gas refinery, petrochemical industries and projects
Fuel factories and mines in Saudi Arabia, large and huge warehouses and tanks, towers and metal structures in desert lands, oil and gas refineries, petrochemical industries and projects, the concept of petroleum engineering in the Gulf countries, the renaissance of the Saudi national economy
Oil refinery factories in the Kingdom of Saudi Arabia, the concept of work in the industrial engineering sector, the quality of machinery and equipment in oil extraction factories, modern technologies in oil and gas production.
Follow up the progress of work in factories and plants, a close-up photo of a Saudi Arabian Gulf engineer working in an oil refinery, working in the field of petrochemical industries and projects, steel pipelines and cables, the concept of gas productivity in the Kingdom of Saudi Arabia
Achieving the industrial revolution, Saudi laboratories and factories, working in the industrial engineering sector, a close-up photo of a Saudi Gulf Arab engineer wearing a jacket and a protective helmet standing with crossed hands at his workplace, youth engineering professions and works, standing confidently and looking at the camera
Huge and large warehouses, petrochemical industries and projects, steel pipelines and cables, a large oil refinery equipped with complex machines in a vast desert landscape and distant mountains, factories and plants in Saudi Arabia, oil and gas refining plant in the industrial area
Petrochemical industries and projects, working in the field of petroleum engineering, a picture from the back of a group of Gulf engineers wearing protective suits and helmets assessing the quality of oil factories in the Kingdom of Saudi Arabia, an oil and gas refining plant in the industrial area
Supervising oil plants and factories in Saudi Arabia, back view of two Saudi Arabian Gulf workers wearing orange protective suits and helmets, pipelines extending from the depths of the sea to the refineries, working in the field of petroleum engineering, oil and gas refinery
Fuel factories and mines in Saudi Arabia, large and huge warehouses and tanks, towers and metal structures in desert lands, oil and gas refineries, petrochemical industries and projects, the concept of petroleum engineering in the Gulf countries, the renaissance of the Saudi national economy
Following the progress of work in factories, Saudi professions and jobs, a picture from the back of two Saudi Gulf Arab engineers wearing work uniforms walking in an oil refining plant, the concept of gas productivity in the Kingdom of Saudi Arabia, blue sky background
Oil factories and plants in the Kingdom of Saudi Arabia, the renaissance of the Saudi national economy, oil and gas refining, the concept of petroleum engineering in the Gulf States, large and huge warehouses and tanks, petrochemical industries and projects
Use of modern techniques and technology in gas production in Saudi Arabia, a picture from the back of a Saudi Arabian Gulf man wearing a helmet and a protective vest following the progress of factory work, engineering professions and jobs, oil refinery background, quality of oil production plants and equipment
Saudi laboratories and factories, work in the industrial engineering sector, a close-up photo of a Saudi Gulf Arab engineer wearing a jacket and a protective helmet standing with crossed hands at his workplace, youth engineering professions and works, standing confidently and looking at the camera
Huge drilling machines used in petroleum extraction, exploration for underground resources in the Kingdom of Saudi Arabia, development of the Saudi economy, petrochemical industries and projects in the Kingdom, pipelines and heavy steel equipment, work in the field of industrial and petroleum engineering.
Follow up the progress of work in factories and plants, a group of Saudi Arabian Gulf engineers working in an oil and gas refining plant, working in the field of petrochemical industries and projects, steel pipelines and cables, the concept of gas productivity in the Kingdom of Saudi Arabia
Pipelines and steel cables, Petrochemical industries and projects, Oil and gas refinery in the industrial area, Factories and plants in the Kingdom of Saudi Arabia, Industrial engineering and equipment, Huge and large warehouses, View of smoke from large industrial facilities at sunset
Huge drilling machines used in petroleum extraction, exploration for underground resources in the Kingdom of Saudi Arabia, petrochemical industries and projects in the Kingdom, pipelines and heavy steel equipment, development of the Saudi economy, work in the field of industrial and petroleum engineering
Renaissance of the Saudi national economy, the concept of petroleum engineering in the Gulf countries, metal towers and structures in the desert, oil and gas refineries in the Kingdom of Saudi Arabia, large and huge warehouses and tanks, petrochemical industries and projects.
Petrochemical industries and projects, working in petroleum engineering, close-up from the back of a Gulf engineer wearing a protective suit and helmet assessing the quality of oil plants in Saudi Arabia, oil and gas refining plant in the industrial area
Oil and gas refineries, petrochemical industries and projects, the concept of petroleum engineering in the Gulf countries, the renaissance of the Saudi national economy, fuel factories and mines in the Kingdom of Saudi Arabia, large and huge warehouses and tanks, towers and metal structures in desert lands
Metal and chemical industries, oil factories in Saudi Arabia, quality of petroleum production plants and equipment, large illuminated industrial facilities, oil and gas refinery, petrochemical projects contributing to the renaissance of the Saudi national economy
Adopting modern techniques and technology in gas production in the Kingdom of Saudi Arabia, quality of oil production laboratories and equipment, cartoon drawings of a Saudi Gulf Arab engineer wearing a protective helmet, following up on the progress of factory work, engineering professions and jobs, petrochemical industrial projects
Working in the field of petrochemical industries and projects, steel pipelines and cables, the concept of gas productivity in the Kingdom of Saudi Arabia, following up on the progress of work in factories and plants, a group of Saudi Gulf Arab engineers working in an oil and gas refining plant
Lighting of towers and metal structures, oil factories and plants in the Kingdom of Saudi Arabia, the concept of petroleum engineering in the Gulf countries, oil and gas refinery, petrochemical industries and projects, the renaissance of the Saudi national economy, large and huge warehouses and tanks
Industrial engineering and equipment, factories and laboratories in the Kingdom of Saudi Arabia, a large oil refinery equipped with complex machinery in a vast desert landscape and distant mountains, petrochemical industries and projects, an oil and gas refining plant in the industrial zone, huge and large warehouses, factories and laboratories in the Kingdom of Saudi Arabia
Huge industrial facilities illuminated at dawn, quality of petroleum production plants and equipment, oil and gas refinery, petrochemical projects contributing to the renaissance of the Saudi national economy, oil factories in the Kingdom of Saudi Arabia, metal and chemical industries
Oil and gas refinery, petrochemical projects contributing to the renaissance of the Saudi national economy, oil factories and plants in Saudi Arabia, lighting towers and metal structures at night, pollution resulting from oil production