The National Iranian Oil Company’s drilling operations and the discovery of hydrocarbon reserves have witnessed a considerable rise over the last five years, the head of NIOC’s Exploration Department said.
“Seismic and geophysical operations in joint oil and gas fields in border regions have gained impetus and NIOC’s next priority is gathering geophysical data to discover new reserves in the Persian Gulf,” Mehdi Fakour was also quoted as saying by IRNA.
Giving a breakdown, the official noted that the number of drilled onshore and offshore oil and gas wells has experienced 100% growth and the length of drilled wells has increased by 36% during the five years.
According to the official, close to $100 million have been spent on two- and three-dimensional seismic surveys since last March, covering 20,000 kilometers in 11 provinces, up fourfold compared to a year ago.
The company needs $1.4 billion to expand its activities and conduct 2D and 3D seismic surveys on 100,000 kilometers of surface areas over the next seven years, he added.
A 2D seismic survey is an exploration method used to create a map of the structures beneath Earth’s surface. The method sends energy waves into the Earth. The different rock formations then reflect the waves back to the surface, where they are recorded over a period of time and converted into a seismic image.
Fakour noted that local engineers have indigenized seismic survey knowhow and talks are underway with neighbors, including Iraq, Oman, Tajikistan and Russia, to transfer expertise and carry out seismic surveys.
According to the official, the process of discovering a new hydrocarbon reserve takes at least seven years, collection of geophysical data requires five years and the rest is spent on seismic surveys and drilling operations.
Aeromagnetic Surveys
NIOC has discovered hydrocarbon reserves in the southwest with the help of aeromagnetic surveys (AMS) conducted by domestic knowledge-based firms.
Fakour said early aeromagnetic studies show that the new reserves hold close to 16 billion barrels of oil in the Zagros area of western Iran.
“Instead of seismic discovery methods, NIOC employs magnetic methods that are faster and more precise,” he said, adding that as they are responsive to lateral variations in rock properties and gravity, magnetic methods are best suited for detecting steep anomalies such as faults.
An aeromagnetic survey is an airborne geophysical inspection performed using a magnetometer aboard or towed behind an aircraft. A magnetometer is an instrument used to measure magnetic forces, especially the earth's magnetism.
The applications of AMS in engineering geology include near-surface geological mapping, structural geology mapping and three-dimensional geological subsurface model construction.
In an aeromagnetic survey, an airplane, flying at a low altitude with a magnetic sensor, flies back and forth in a grid-like pattern over an area, recording disturbances in the magnetic field.
According to Fakour, plans are underway to study 175,000 km of Iran’s area with aeromagnetic methods.
“Contracts worth $400 million were signed with local and foreign companies to implement geological survey nationwide last year and new agreements worth $600 million will be concluded in the near future,” he said.
The official said the development of oil and gas fields will secure energy supply in the future.
Oil experts believe that the economy will struggle if the oil industry, the engine of economic growth, does not get the long-awaited impetus after years of underinvestment.
Fakour said reliance on geophysical and seismic data can help accelerate the discovery of small- and medium-sized fields.
“NIOC’s Exploration Department is undertaking nine seismic and geophysical initiatives across the country simultaneously and as soon as they yield positive results, drilling operations will follow,” he said.
“Geophysical data, used to provide information on the physical properties of the Earth's surface and subsurface, play a key role in locating hydrocarbons, minerals and other natural resources.”
Recoverable Reserves
In the past 40 years, 73 oil and gas fields have been discovered in Iran and exploration conducted at hydrocarbon fields shows Iran’s recoverable gas reserves have risen by 283 billion.
“They include 36 oilfields and 37 gas fields, 26 of them are joint fields,” Fakour said.
Iran (34 trillion cubic meters) and Russia (32.6 tcm) hold the largest proven gas reserves in the world.
In addition to lack of investment, the oil and gas industry is facing new challenges, one of which is its high consumption of water and energy resources, which subject it to increasingly stringent environmental standards.
This constrains them to rethink extraction, production and distribution methods to obtain or maintain their operating license.
They also have to provide guarantees and ensure transparency in the environmental discharge of their activities.
According to the official, a total of 19 oil and gas fields, including 48 reservoirs, were discovered in the past eight years.
“As of 2014, 10 gas fields were discovered with total in-place reserves of 2 tcm, as well as nine oilfields containing 60 billion barrels of in-place oil,” he added.
Elaborating on some of the provincial discoveries, Fakour said the gas fields of Pazan in Fars Province, Khar-Tang in Bushehr Province and Charak in Hormozgan Province, as well as Yadman and Sepehr oilfields in Khuzestan Province, are among major deposits discovered during the period.
