As an artery of the national economy and strategic resources industry, the Chinese oil industry is entering a new historical stage in which mining costs are higher and mining risks are greater. Oil and gas resources are relatively poor in China, and the country’s geographical environment is rather complex. Consequently, the difficulty and cost of mining is very high. Most onshore oil fields are moving into middle and later development periods. The Chinese continental shelf is rich in petroleum and gas. Accordingly, marine petroleum exploitation has become inevitable. China's offshore oil development technology, however, is relatively backward, and it cannot satisfy the need for mining; consequently, international ocean petroleum cooperation has become an inevitable choice for China. In recent years, China's offshore oil development has been successful, but the frequency of problem incidents is increasing in the field of international petroleum cooperation. For example, in May 2010, an oil spill accident occurred on a drilling platform called ONE NUMBER of South China Sea, which is a platform belonging to CNOOC (the China National Offshore Oil Corporation), Tianjin branch; the tilting accident of the Shengli oil field drilling platform happened in September 2010, and the oil leak of COPC (ConocoPhillips China) in Bohai Bay happened in June 2011. The increase in the number of these emergencies seriously threatens people's health, life, and property security, and causes huge economic loss and environmental harm. Effective analysis of the internal mechanism of those incidents, which cause marine environmental pollution problems, may provide a better solution or new insights into international ocean petroleum cooperation. In addition, research results may provide intellectual support for environmental protection in China and an analytical framework for similar incidents. In summary, the COPC Bohai Gulf oil spill is a very typical ocean contaminative event for international petroleum cooperation and, using that event as the research object, we adopt an economic game theory point of view, analyze the deep reasons for excessive development, and provide a basis for marine environmental legislation and management.

The international petroleum cooperation marine environmental pollution issue is considered to be a branch of emergency management. Emergency management is an active research field and many researchers have made numerous contributions in this area. Graham T. Allison published Essence of Decision, which brought emergency management and scientific decision making into the management discipline, and provided a theoretical basis for emergency management research [1G.T. Allison, and A. Graham, Essence of the Decision, Pearson Education: USA, 1999.]. Haddow, G., Bullock, J., and Coppola, D.P. summarized the historical context and the present-day trend of emergency management, and provided significant practical, real-world experiences through documented case studies [2G. Haddow, J. Bullock, and D.P. Coppola, Introduction to Emergency Management., Butterworth-Heinemann: UK, 2013.]. Van De Walle, B., Turoff, M., and Hiltz, S.R. described the developed process of the combination of information systems and emergency management, and presented several typical case analyses and practical technologies [3B. Van De Walle, M. Turoff, and S.R. Hiltz, Information Systems for Emergency Management., Routledge: London, 2014.]. Comfort, L.K., Waugh, W.L., and Cigler, B.A. reviewed the changeable process of research and practice in emergency management in the public administration field and its impact [4L.K. Comfort, W.L. Waugh, and B.A. Cigler, "Emergency management research and practice in public administration: Emergence, evolution, expansion, and future directions", Public Adm. Rev., vol. 72, pp. 539-547, 2012.
[http://dx.doi.org/10.1111/j.1540-6210.2012.02549.x] ]. Handmer, J. and Dovers, S. provided a policy and institutional framework for emergencies and disasters [5J. Handmer, and S. Dovers, Handbook of Disaster Policies and Institutions: Improving Emergency Management and Climate Change Adaptation., Routledge: London, 2013.]. Seppänen, H., et al. discussed the critical information needs for cooperation, a method for describing communication, and the components of system trust in emergency operations [6H. Seppänen, J. Mäkelä, P. Luokkala, and K. Virrantaus, "Developing shared situational awareness for emergency management", Saf. Sci., vol. 55, pp. 1-9, 2013.
[http://dx.doi.org/10.1016/j.ssci.2012.12.009] ]. Owen, C., et al. developed a four phases’ teamwork model for complex multi–team coordination in emergency management [7C. Owen, C. Bearman, B. Brooks, J. Chapman, D. Paton, and L. Hossain, "Developing a research framework for complex multi–team coordination in emergency management", Int. J. Emergen. Manage, vol. 9, pp. 1-17, 2013.
[http://dx.doi.org/10.1504/IJEM.2013.054098] ]. Liu, L., et al. presented a risk-based framework for dynamic decision making for emergency management [8L. Liu, Y. Liu, X. Wang, D. Yu, K. Liu, and H. Huang, "Developing an effective 2-D urban flood inundation model for city emergency management based on cellular automata", Nat. Hazards Earth Syst. Sci., vol. 51, pp. 381-391, 2015.
[http://dx.doi.org/10.5194/nhess-15-381-2015] ]. Those researchers made many research contributions. Additionally, many researchers have applied emergency management to different fields (e.g., medical science [9C. Young, K.Y. Wong, and L.K. Cheung, Effectiveness of Educational Poster on Knowledge of Emergency Management of Dental Trauma–Part 1. Cluster Randomised Controlled Trial for Primary and Secondary School Teachers., vol. 8, Plos One, no. 9, p. e744833, 2013.], city management [8L. Liu, Y. Liu, X. Wang, D. Yu, K. Liu, and H. Huang, "Developing an effective 2-D urban flood inundation model for city emergency management based on cellular automata", Nat. Hazards Earth Syst. Sci., vol. 51, pp. 381-391, 2015.
[http://dx.doi.org/10.5194/nhess-15-381-2015] ], educational management, and other areas [10J. Liu, and X. Fan, "A research on foreign students emergency management system in China", In: IEEE International Conference, IEEE, 2013, pp. 269-73.
[http://dx.doi.org/10.1109/GSIS.2013.6714797] ]).

Some scholars have provided in-depth research regarding the emergency management of marine environmental pollution. Groner, M.L., et al. emphasized the necessity of surveillance for marine diseases and proposed several pieces of advice for marine disease emergencies [11M.L. Groner, J. Maynard, R. Breyta, R.B. Carnegie, A. Dobson, and C.S. Friedman, "Managing marine disease emergencies in an era of rapid change", Phil. Trans. R. Soc. B., vol. 371, p. 20150364, 2016.
[http://dx.doi.org/10.1098/rstb.2015.0364] ]. Yoo, B., Oh, K., and Baek, J. studied emergency response systems and recovery apparatuses for oil spill accidents in marine environments and provided a developed oil diffusion apparatus to minimize casualties [12B. Yoo, K. Oh, and J. Baek, "A Study on Improved Emergency Management System-Focused on Response to Diffusion of Oil Spilled in Marine", J. Korean Soc. Safety, vol. 30, pp. 83-89, 2015.]. Kirby, M.F., Gioia, R., and Law, R.J. described eight principles of effective post-spill monitoring programs in marine environments [13M.F. Kirby, R. Gioia, and R.J. Law, "The principles of effective post-spill environmental monitoring in marine environments and their application to preparedness assessment", Mar. Pollut. Bull., vol. 82, no. 1-2, pp. 11-18, 2014.
[http://dx.doi.org/10.1016/j.marpolbul.2014.01.038] [PMID: 24576390] ]. Kristiansen, S. summarized classic analysis approaches and technologies to monitor marine pollution and predict resulting loss [14S. Kristiansen, Maritime Transportation: Safety Management and Risk Analysis., Routledge: London, 2013.]. Although many researchers have produced numerous studies, marine environmental pollution is developing rapidly, and we need to continue recording experiences of marine pollution incidents and perfecting the theory of emergency management.

The research of game theory presents a strategy question; participants select a strategy when they confront, compete, or face the same situation. A game requires at least four elements: game participants, the collection of all strategies that are selected by participants, the sequence of the game, and the benefit of the game. Game theory entered the mainstream of economic research in the 1980s. The Nash equilibrium expanded game theory from cooperative to noncooperative, and the evolutionary game is an important branch of game theory from the 1970s. Game theory was gradually perfected from the 1980s to the 1990s and it became an important and core analysis method. Game theory is used in all aspects of economic theory (e.g., dynamic noncooperative game [15D.A. Castañón, "Dynamic Non cooperative Games", In: Encyclopedia System Control, Springer: London, 2015, pp. 323-329.] and Bayes-Nash equilibria [16R. Gomes, and K. Sweeney, "Bayes–nash equilibria of the generalized second-price auction", Games Econ. Behav., vol. 86, pp. 421-437, 2014.
[http://dx.doi.org/10.1016/j.geb.2012.09.001] ]).

If the production of the oil fields is 10,000 barrels, the price of one barrel is 100$, the average cost is 10$, so that the revenue is 90$ for one barrel, and the exchange of dollars into RMB is 6.22, F_g is 200 thousand RMB, new F_g is 3 billion RMB, C_ge is 120 billion RMB (which is determined based on the oil spill in the Gulf of Mexico), C_gm is 20,000 thousand RMB, L_gn is 20,000 thousand RMB, L_kn is 40,000 thousand RMB, P_d is one third, b is 2000 barrel, X is one third, L_knP_dn is 0.1 billion RMB, and Z is one third.

According to the above value, the optimal result from the two dimensions is . From equation (8), COPC revenue, government revenue, the probability of government finding the overdevelopment, and the cost of government have a functional relation. If, according to current Chinese environmental law, 200,000 RMB is the maximum fine for environmental pollution, the probability that COPC has an intention to make the overdevelopment decision is 300. If the maximum fine is 3 billion, the probability for overdevelopment is 2%, so a high fine can effectively prevent overdevelopment. Because the optimal point is influenced by three parameters, we can make a sensitivity analysis for them. As shown in Fig. (2), C_gm has a positive relationship with Y, and F_g, and P_d has a negative relationship with Y. When other parameters do not change, F_g must improve to 2 billion fines, which can significantly prevent overdevelopment. When other parameters do not change, P_d is 1, and the action of over-development will have a 100 percent chance of occurring. Through sensitivity analysis of the model’s parameters, we find that improving F_g sharply is the simple and direct method to prevent oil companies from overdeveloping.

Fig. (2) The sensitivity analysis of three parameters of .

From the three-dimensional model, COPC production action will have two extreme points; one is absolute overdevelopment and the other is absolute moderate development, as shown in Fig. (3). From the above analysis, we can assume COPC is at the state of making the overdevelopment choice, Y is 1, and if we want to make the point unstable, the evolutionary strategy should satisfy ; in that situation, we can transform the equation, . If the fine is 200 thousand RMB, then is false, so if we want COPC to make the moderate development choice, the fine should be 3.66 billion. This fine can make the overdevelopment points unstable, and a high fine will force COPC managers to make the moderate development decision.

Fig. (3) ConocoPhillips balance transfer trajectory under punishment constraints.

The oil spill in the Bohai Gulf occurred as the necessary result of China’s current international petroleum cooperation, and as the result of a multi-player game. The overdevelopment strategy of COPC will cause oil spilling, and it is the wise selection for COPC. From the above analysis result, enhancing the international petroleum cooperation contracts’ selection, setting reasonable fines for overdevelopment and pollution, strengthening supervision of societal opinion for international petroleum cooperation, setting the industry credit admittance mechanism, and constructing an impartial, transparent, and efficient mechanism will reduce the overdevelopment and pollution of Chinese international petroleum cooperation. These research results can help industry superintendents handle and prevent a similar event.

We recommend strengthening the international petroleum cooperation’s contracts’ selection, and breaking the value chain of the local petroleum company and the international petroleum company. At the oil leak in Bohai Bay, the local petroleum company and the international petroleum company formed a community of interests through production share contracts; they behaved similarly in the subsequent accident process. Generally speaking, local petroleum companies should supervise international petroleum companies, but in this contract, it is easy to neglect this important responsibility, thereby harming the international marine environment. Contracts, like risk service contracts and pure service contracts, that can mitigate the risk, should be adopted.

We recommend increasing the fines for overdevelopment and pollution to add to the petroleum enterprises’ costs for unlawful behavior. Currently, China’s Environmental Protection Law specifies a maximum fine of 3 to 20 thousand RMB; this law cannot satisfy the needs of reality. From the analysis of two dimension game between COPC and government, we can see that whether COPC makes the overdevelopment decision depends on the government’s fine, the probability of the government discovering the overdevelopment, and the cost of the government’s supervision. From the analysis, we find that, if the fine is more than 0.6 billion, it can effectively suppress the trend of overdevelopment decisions by COPC. When societal opinion is added, the fine will be raised to 3.66 billion RMB. From this analysis, we can see that three-dimensional game analysis is better than two-dimensional game analysis.

We recommend strengthening the effect of societal opinion in supervising international petroleum cooperation. Installing industry credit admittance mechanisms and constructing impartial, transparent, and effective accountability mechanisms will be effective methods of preventing pollution and enhancing social responsibility. From the analysis, we see that government can improve the efficiency of supervision with the help of societal opinion. Especially today, societal opinions can decrease the asymmetry of government supervision, so that government must provide an avenue for societal opinions (e.g., credit industry credit admittance mechanisms and impartial, transparent, and effective accountability mechanisms, which will give societal opinions a greater role in protecting our environment).