After nearly three decades since the conclusion and implementation of BUYBACK CONTRACTs in the oil and gas industry in Iran, objections to this CONTRACT, particularly from the perspective of foreign investors has been revealed. Failure to allocate a share of the produced oil and gas to foreign investors and subsequently discussing possibility of reserve recognition, short terms of BUYBACKs and non participation of oil companies in production period, non admissibility of BUYBACKs fiscal system for foreign investors and the Iranian content are among many challenges which have been set forth by CONTRACTors. In order to solve such problems and attract expertise and financial resources to the Iranian oil and gas projects, a new petroleum CONTRACT has been introduced by Iran, the so-called Iranian Petroleum CONTRACT (IPC). The present article will comparatively analyze BUYBACK and IPC in three aspects naming ownership, reservoir recognition and fiscal regime and will conclude that under IPC, the same as BUYBACK, ownership of petroleum in situ and produced oil and gas vest by the government. Also, IPC’ s CONTRACTor, the same as the CONTRACTor under the BUYBACK, is able to recognize oil and gas reserves in accordance with the PRMS guideline, and its fiscal regime although in some areas has been improved, some objections can be raised.

Signing Oil CONTRACTs with international oil companies for upstream and downstream operations in Iran's oil industry has a long history. After the discovery of oil, the first international oil CONTRACT was signed in Iran. Different types of oil CONTRACTs have been used in Iran. In most cases, the adequacy of CONTRACTs in terms of economic benefits has raised questions and ambiguities for Iran. To investigate this topic, the gas BUYBACK CONTRACTs are evaluated from an economic point of view. In order to assess the results more carefully, these CONTRACTs are compared with the Production Sharing CONTRACTs. Phases 2 and 3, and also 4 and 5 of South Pars Gas Field have been selected for this paper. Since these projects have been awarded in the form of buy-back CONTRACT, in addition of defining different scenarios, the Production Sharing CONTRACT for the project has been simulated. After finding the best scenario in terms of the production sharing CONTRACTs for both projects, we found that for phases 2 and 3 of the South Pars, the Production Sharing CONTRACT and for phases 4 and 5, the BUYBACK CONTRACT, are proved to be more favorable for Iran.

The choice of financial regime in oil-rich countries depends on proven reserves, exploration and production costs, geological characteristics, political risks, and oil market conditions. In this article, CONTRACTual components of three CONTRACTs IPC, BUYBACK, and PSC are introduced using Visual Basic programming language, and a model structure for a 42-season period scenar-io with oil prices is created. Also, modeling based on the parameters of the Shadegan oil field is another innovation of this work. The aim of this research is to investigate the effective indica-tors in the oil and gas industry CONTRACTs based on oil price scenarios. The results of this study show that many of the constraints of the reservoir owner country have been modified in the direction of protecting oil fields and effectively controlling CONTRACTor's fees in modified mutual agreement and production sharing CONTRACTs, and the financial system of the new oil CONTRACTs is more efficient in case of an oil price increase and in the final years of production compared to production sharing and BUYBACK CONTRACTs. In this study, comparing indicators such as internal rate of return, payback period, profitability index, and the share of both parties in the CONTRACT based on real and simulated data showed that entering into new oil CONTRACTs in Iran, especially IPC in the Shadegan oil field, can protect the oil field, prevent uncontrolled oil extraction, and control CONTRACTor's revenues, leading to lower costs and higher revenues compared to BUYBACK and production sharing CONTRACTs for the host country (Iran).

Production Sharing CONTRACT (PSC), BUYBACK CONTRACT (BBC) and Iran Petroleum CONTRACT (IPC) are considered as three rival CONTRACTs in upstream oil & gas field in Iran. So, decision makers in the process of selecting a suitable CONTRACT from the set of three mentioned CONTRACTs consider a set of jurisprudential, legal and economic conditions about these CONTRACTs. In this paper with the aim of explaining the economic capacity of the three CONTRACTs in comparision with each other and based on Static Optimal Methods, we compare these contacts in terms of two important economic indices of optimal investment and oil production and then, we prioritize them. Finally, we have concluded that upstream CONTRACTs of Production Sharing, Iran Petroleum CONTRACT and BUYBACK are ranked in the first, the second and the third place from the perspective of optimal investment level, and from the perspective of optimal oil production level, in case of more participation of private sector and less interference of public ector, these CONTRACTs are ranked the first, the second and the third, respectively.

Iran's oil and gas industry requires investments of US$ 15 billion in the short-term and over US$ 50 billion in the medium term. Iran tries to interest international oil companies (IOC) in investing in Iran's oil and gas business by offering BUYBACK CONTRACTs. Under a BUYBACK CONTRACT an IOC invests and when production starts the field is handed over to the National Iranian Oil Company (NIOC) or one of its representatives. The IOC gets its costs and an agreed upon profit paid out of the oil and/or gas gross profits, assuming the field produces as agreed upon and the international energy prices are high enough. According to the Iranian government the BUYBACK CONTRACT contains sufficient incentives for an IOC to invest in Iran. The IOCs, however, disagree. They claim that they solely bare the risks in a BUYBACK CONTRACT, whereas the Iranian counterpart receives all windfall profits. Furthermore, the IOCs claim that the utilization of Iran's oil and gas reserves will be sub-optimal if they are not involved in optimizing long-term recovery. This paper formulates the BUYBACK CONTRACTs as such one could compare with other CONTRACTual framework like production sharing. Also the paper offers optimization solutions for BUYBACK CONTRACTs as such Iran could pay the minimum amount to the investor.

Maximization of the economic value of the exploitation of oil and gas resources in economic literature as the target state (as owner of the resource) is known. This goal is achievable when the CONTRACT conditions (which regulate the behavior of investors in the exploitation of the reservoir) is also taken into account. In this paper, the dynamically optimal oil production in the one of the Iran's oil fields in the South West with a BUYBACK CONTRACT framework is considered as a case study by the use of Bellman equation in Matlab program and with regard to expected price path and interest rate scenario, the results shows that the optimal production path traced by model in comparison to path specified in the CONTRACT is different. In addition, Comparison these results and CONTRACTual profile to the expected behavior of international oil companies that is proposed high production level in early years of reservoir life cycle are consistent. Note that, any changes in the CONTRACT parameters would the constant parameter of cost function and minimum production rate condition in the model. According to the have been that in Status of High expectations of prices, Optimum path specified in the model, there is no reaction to changes in these factors.

The purpose of this study is to compare the economic efficiency of Iran's petroleum CONTRACTs, BUYBACK CONTRACTs, and production-sharing CONTRACTs. This study also determined the optimum path for production and drilling operations in the Yadavaran oil field which has special importance because it is a joint field with Iraq. It was estimated using real field data and the SQP algorithm by MATLAB software. First, the objective function, the constraints of each CONTRACT model, and the cost function are defined and expressed based on field data. For the objective function, the oil price is determined based on the reference price scenario and based on the forecast of the US Energy Information Administration (EIA). Cao et al (2009) 's cost function model is also modified by using historical field data (first development phase data) to be applied to the study field. The results show that the most efficient oil CONTRACT is the Iran petroleum CONTRACT, with a low floor for capital costs and no limit to the number of drilled wells. it was proved that the BUYBACK CONTRACT with the ceiling of capital costs incompatible with the recovery coefficient has recorded the lowest efficiency. Also, the Iran petroleum CONTRACT can be a good alternative to the BUYBACK CONTRACT, because it can well solve the problems of the BUYBACK CONTRACT, especially for joint oil fields where the priority of the objective function of the maximum cumulative production over the objective function of the maximum present value of the total profit is more desirable.

Companies employ several forms of cooperation to reach success in the global competitive market. Coordination models seek to find the practical solution to encourage supply chain members to make decisions to improve overall profit. Note that, cooperation CONTRACTs are useful tools to make supply chain members behave coherently and coordinately with each other in order to gain SC's profit as final purpose. This paper aims to determine the most appropriate CONTRACT that can make cooperation between SC levels. In this case supply chains and cooperation CONTRACTs were reviewed and as a result of this study. Afterwards, a two echelons SC and mentioned CONTRACTs in the title chose are investigated. By considering the game theory approach, static games by complete information and Nash equilibrium as a solving method and probabilistic demand of consumers, initial profit function models of SC echelons were designed and subsequently, the secondary models redesigned with the consideration of the specific circumstances of each CONTRACT. Then, some experiments were designed by MINITAB software and solved by EXCEL and LINGO software. Eventually, by analyzing outputs, rebate CONTRACT is determined as the most appropriate way of establishing cooperation among the SC levels.

Leading towards sustainable water use and optimal allocation of water resources, water banks are efficient institutions. Water banks facilitate the trade of surface water and groundwater and engender water security. This study develops a couple agentbased groundwater model in NetLogo platform to assess economic and hydrologic impacts of water bank's water BUYBACK programs in the case study of Rafsanjan Plain. Results show that BUYBACK programs can temporarily ameliorate the condition of the Rafsanjan Aquifer, so there is a need for taking other measures, like the cap-and-trade policy, in conjunction with BUYBACK program. The drawdown of aquifer's unit hydrograph reduces from 80 to 58 cm per year owing to the BUYBACK program. Moreover, the water bank improves the economic situation of the area as it increases the farmers' net benefit by 6 percent.