CC BY
56
GEOLOGICAL-MINERALOGICAL SCIENCE
OIL SPILLS FROM OFFSHORE DRILLING AND DEVELOPMENT:
CAUSES AND EFFECTS ON PLANTS AND ANIMALS 1 2 Akhmetov R.R. , Krainov S.A. (Russian Federation)
Email: [email protected]
1Akhmetov Radmir Rustemovich - Student;
2Krainov Sergei Alexeevich - Student, PETROLEUM ENGINEERIND DEPARTMENT, SAINT PETERSBURG MINING UNIVERSITY SAINT PETERSBURG
Abstract: article investigates causes of oil spills from offshore drilling and effect on plants and animals. The estimations were made to assess the consequences of spilled oil. For example, it was calculated that 1106460 birds, 110340 turtles and 28260 mammals died because of incident in the Gulf of Mexico and the index of death for 1 square km accounts for 6.5, 0.65 and 0.17 respectively, It was also found put that in the North Sea, Ekofisk and Aldfisk platforms there were changes in benthic community composition along a pollution gradient including a loss of rare species and increases in abundance of pollution tolerant species near platform, sampling gear: 0,1 m2, sieve size: 1 mm. Spills can be caused by people making mistakes or being careless, equipment breaking down, natural disasters such as hurricanes, deliberate acts by terrorists, countries at war, vandals, or illegal dumpers. Keywords: offshore drilling, oil spills, animals welfare, offshore development, pollution.
РАЗЛИВЫ НЕФТИ ПРИ БУРЕНИИ И РАЗРАБОТКЕ МЕСТОРОЖДЕНИЙ НА ШЕЛЬФЕ: ПРИЧИНЫ И
ПОСЛЕДСТВИЯ ДЛЯ РАСТЕНИЙ И ЖИВОТНЫХ
12 Ахметов Р.Р. , Крайнов С.А. (Российская Федерация)
1Ахметов Радмир Рустемович - студент;
2Крайнов Сергей Алексеевич - студент, кафедра транспорта и хранения нефти и газа, Санкт-Петербургский горный университет, г. Санкт-Петербург
Аннотация: в статье анализируются причины разливов нефти при бурении на шельфе и последствия для животных и растений. Были проведены расчеты, чтобы оценить вред, наносимый разливами. Например, было посчитано, что 1106460 птиц, 110340 черепах и 28260 млекопитающих погибло в Мексиканском заливе при разливе нефти. На 1 квадратном километре погибло 6.5, 0.65 и 0.17 живых существ. Было также обнаружено, что при разливах в Северном море, Экофиске и Алдфиске последствия катастрофы были следующими: потери редких видов животных либо полное исчезновение. Разливы могут возникать по причине ошибок людей, поломок оборудования, природных катаклизмов, актов терроризма, вандализма. Ключевые слова: бурение на шельфе, разливы нефти, благополучие животных, разработка месторождений на шельфе, загрязнение.
Oil spills into rivers, bays, and the ocean most often are caused by accidents involving tankers, barges, pipelines, refineries, drilling rigs, and storage facilities. Spills can be caused by:
1. people making mistakes or being careless.
2. equipment breaking down.
3. natural disasters such as hurricanes, terrorism.
Let us take a more specific look at the process to understand what are the spills caused by equipment breaking down. This is a brief description: to find oil reserves in deepwater sites, oil companies use electronic equipment that sends and measures sound waves that penetrate the ocean floor and bounce back. Sophisticated software allows the companies to convert the returning sound waves into 3-D images of what lies below the ocean floor. If the company detects a reserve, it drills an exploratory well to confirm the finding. Once the oil reserve is confirmed, oil companies drill into the sea-floor and place large pipes that draw out the oil. The drilling process is like pushing huge drinking straws down into the ocean floor until they reach the oil reservoir. More specifically the process of drilling and the blowout preventer structure are presented on figure 1. When the pipes puncture the reserve, the pressure on the underwater oil forces it up through the pipes. To control the oil, drilling operations use valves that can increase, decrease, or shut off the oil flow. The process of offshore drilling is described by the next steps [8]:
1. Environmental footprints and regulatory reviews.
2. Environmental management of seismic and other geophysical work.
3. Subsea drilling, well operations and completions.
4. Well control management and response.
5. Offshore production facilities and pipelines, including arctic platform designs.
6. Offshore transportation.
Fig. 1. Diagram of Well and Blowout Preventer (offshore drilling)
Effects on benthic communities:
Seabirds are strongly affected by oil spills. When they get covered in oil, the heavy oil weights down the birds and is unable to fly. Often, the bird will then attempt to rid itself of the oil lining, and will eat the oil. As the oil is poisonous, the bird will either die or suffer greatly from being poisoned. All these lead to the bird's inability to carry out its natural life processes such as hunting for food, and eventually, the bird will die, unless it is rescued and
given proper treatment. Furthermore, the oil penetrates and opens up the bird's plumage, reducing its insulation activity and making it susceptible to hypothermia and temperature fluctuations, as well as less buoyant in the water.
Another group of animals strongly affected by oil spills are the Sea Otters. Otters have air bubbles located in the fur of their bodies which enable them to float and survive the cold waters. When oil spills occur, oil covers the otter's bodies and often covers these air holes. As a result, otters may die of hypothermia, are unable to swim properly, and eventually die.
The third group of animals affected strongly are Killer Whales. Oil spills have led to the endangering of killer whales. Oil affects the killer whales in two ways. Firstly, it plugs up the blowholes of the killer whales, and the killer whale will be unable to breathe. Secondly, the Killer Whale may eat fish that swam through the oil, or fish already poisoned by the oil, and the killer whales too will get poisoned by the oil, and will die [7]. Lastly, oil spills affect small organisms. Oil spills affect small organisms living in the sea, such as plankton, and larval fish, as well as bottom-dwelling organisms like oysters, seaweed, mussels. When these organisms die due to the oil, this affects the food chain, Fish who prey on these animals will have difficulty finding food, and may die. This will in turn affect their predators and so on.
Studies have shown that the environmental damage of oil spills are far greater than originally thought. The hydrocarbons in petroleum-based oil is able to negatively impact marine life at concentrations as low as one part per billion. The heavier components of crude oil such as polycyclic aromatic hydrocarbons cause the most damage. Although being less toxic then lighter components such as benzene and toluene, unlike these components they are not volatile and do not evaporate easily. The oil mixes deeply into pebbles or sandy beaches, and remains there for months or years [8]. These are the pictures of different animals died as a result of oil pollution after Montara disaster (Figure 2).
^ -
^ >
Fig. 2. Poor animals abandoned by people in Montara after oil spill. Source: (CBS 8), (News Limited), (http://spanish. china. org. cn/photos/txt/2010-06/23/content_20325213.htm)
The same type of image is provided for Mexican incident (Figure 3).
Fig. 3. Poor animals abandoned by people in Mexico after oil spill. Source: (AP Photo/Charlie Riedel), (AP Photo/Gerald Herbert), (Mario Tama/Getty Images)
From this images we could see that independently from the location of the oil spill, the harm to animals is the same. All of them suffer from pollution and receive injuries or die.
We want to try to show the real numbers about the damage to poor birds, turtles, mammals and fish on the example of the disaster in the Gulf of Mexico. These are the calculations and the histogram (Figure 4). Species totally died because of Mexican Gulf oil spill
Sd = n xm, (1)
The index, which shows the number of animals, which died because of 1 square kilometre of oil in the sea:
o m >n
S =—2-, where (2)
S2
S2 - the area of the Gulf of Mexico spill
n - number of species daily died in the Gulf of Mexico from oil pollution
m2 - number of days needed to clean the spill in Mexico
Example of the calculation for birds:
S = 6147 >180 = 1106460 birds totally died
0 6147 >180 ^
S =-= 6,5 birds/km
170000
Table 1. Daily dead wildlife because of the Gulf of Mexico oil spill
Species daily died Species totally died The index of death for 1 square km, birds/km
Birds 6147 1106460 6.5
Turtles 613 110340 0.65
Mammals 157 28260 0.17
Fig. 4. Number of totally died species after the spill in the Gulf of Mexico
Effects on plants in the sea: The oil forms a thick layer on the water surface, and this layer blocks out light and prevents gaseous exchange. When this happens, not only will the plants not be able to photosynthesise, animals underneath the affected area will find that the supply of oxygen slowly diminishes, and is unable to be continuously replenished by the environment. When plants cannot photosynthesise, they eventually die, leading to a vicious effect on the food chain, ultimately affecting all animals. The table of biotic community change from of spills is provided to demonstrate effect on environment from disasters.
Sedi ment type Tra
Locati on Well information Barium Hydroc arbon ce met als Biotic community change
100 m, increases in
Gulf of Meixc o Hard botto m 3 platforms Elevated within close proximity to platform Elevate d within close proximit y to platform Cd, Hg, Pb, Zn deposit-feeding nematodes and polychaetes in the meiofauna. Sampling gear: 0,25 m2, sieve size: 500 micrometres, benthic
community composition significantly different within 50 m [1]
Changes in benthic
North Sea, Ekofis Fine or very fine sand 903 tons oil-based drilling mud discharged from 19841985 at Ekofilsk community composition along a pollution gradient including a loss of rare
k and Aldfis k platfor ms 20003000 m 20003000 m species and increases in abundance of pollution tolerant species near platform, sampling gear: 0,1 m2, sieve size: 1 mm [2]
Changes in benthic
North Sea. 65- Sr, Cu, Cd community along a pollution gradient including a loss of rare
Valhal l, Gyda platfor ms 69 m; 65m; 180 m 15650 tons; 19720 tons; 5240 tons 40006000 m 40006000 m species and increases in the abundance of pollution tolerant species near platforms, ordination. Sampling gear: 2 0.1 m2 Sieve Size: 1 mm [3]
Mid- 120
Atlant ic Contin ental m. Medi um/ fine Single exploratory well 1.6 km, 21-fold increase in Ba - - 150 m, lower species diversity and abundance. Sieve size: 0.5 mm [6]
Shelf sands
References in English / Список литературы на английском языке
1. Gray J.S., Clarke K.R., Warwick R.M., Hobbs G. ,1990. Detection of initial effects of pollution on marine benthos: an example from the Ekofisk and Eldfisk oil fields, North Sea. Mar Ecol Prog Ser 66:285-299.
2. OlsgardF., Gray J.S., 1995. A comprehensive analysis of effects of offshore oil and gas exploration and production on the benthic communities of the Norwegian continental shelf. Mar Ecol Prog Ser 122:277-306.
3. Roger С., Heather R., Stern A. Preventing offshore oil spills. Gold, Russell and Ben Casselman, 2010. Far Offshore, a Rash of Close Calls. Wall Street Journal. Dec. 8. Business.
4. Mooney C., 2011. Oil Spills and offshore drilling. Energy and environment, San Diego.
5. Sam Mannan M., Rashid Hasan A., Eric van Oort, 2016. Human Factors and Ergonomics in Offshore Drilling and Production: The Implications for Drilling Safety. Ocean Energy Safety Institute Dec.
6. Ellis J., Gail S. Fraiser, 2012. Discharged drilling waste from oil and gas platforms and its effect on benthic communities. Marine Ecology Pgogress Series June.
7. Report of the Montara Wellhead Platform Incident. Report of the Incident Analysis Team. March 2010. Australian Maritime Safety Authority.
8. Fish and Wildlife collection report: June, 10, 2010.
References / Список литературы
1. Грэй Д.С., Кларк К.Р., Варвик Р.М., Хоббс Г., 1990. Регистрация эффектов загрязнения морской среды обитания: пример месторождений Экофиск и Элдфиск. Мар Экол Прог Сер 66:285-299.
2. Ольсгард Ф., Грэй Д.С., 1995. Сравнительный анализ послкдствий морского бурения на морские виды Норвежского континетального шельфа. Мар Экол Прог Сер 122:277-306.
3. Роджер К., Хэтер Р., Стерн А. Предотвращение разливов нефти при морском бурении. Голд Расселл и Бэн Каслман, 2010. Бурение на отдаленном шельфе. Журнал Уолл-Стрит. 8 декабря. Бизнес.
4. Муни С., 2011. Разливы при морском бурении. Энергия и окружающая среда, Сан Диего.
5. Сэм М., Рашид Х.А., Эрик ван Оорт, 2016. Человеские факторы и эргономика при морском бурении: Меры безопасности при бурении. Институт сохранения энергии в океане, декабрь.
6. Эллис Д., Гэйл С.Ф, 2012. Влияние разливов нефти при морском бурении на морскую среду. Морская экология. Серия прогресс, июнь.
7. Отчет о разливе при морском бурении (Монтара). Отчет аварийной бригады. Март, 2010. Служба Австралии (морская безопасность).
8. Коллективный отчет о состоянии диких животных и рыб (10 июня 2010).
MODELING AND CHARACTERIZATION OF ACHIMOV GAS-CONDENSATE RESERVOIR GEOLOGICAL, HYDRAULIC
SECTOR AND GEOLOGICAL CROSS SECTION 1 2 Akhmetov R.R. , Krainov S.A. (Russian Federation)
Email: [email protected]
1Akhmetov Radmir Rustemovich 4-year student;
2Krainov Sergei Alexeevich 4-year student, PETROLEUM ENGINEERIND DEPARTMENT, SAINT PETERSBURG MINING UNIVERSITY, SAINT PETERSBURG
Abstract: geological and hydrodynamic sector model of the deposit were developed in this paper. The geological cross section of the complex-lenticular structure of the Achimov strata was plotted. Then were described some crucial parameters of Achimov field and imaged on the figure. Porousness varied from 16 to 19%, but for considered 4 square km area it was equal to 16. Oil saturation was between 35 and 60%. It was found out that formation pressure and temperature were 270-310 MPa and 81-96°C respectively. The occurrence depth is 2750-3850 m. Thickness of permeable beds is up to 1-3 m.
