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The fuzzy clustering technique is one of the ways of organizing data that presents special patterns using algorithms and based on the similarity level of data. In this study, in order to cluster the resulting data from the Babakoohi Anticline joints, located north of Shiraz, K-means and genetic algorithms are applied. The K-means algorithm is one of the clustering algorithms easily implemented and of fast performance; however, sometimes this algorithm is located in the local optimal trap and cannot respond with an optimal answer, due to the sensitivity of this algorithm to the centers of the primary cluster. In addition, it has some basic disadvantages, such as its inappropriateness for complicated forms and also the dependency of the final result upon the primary cluster. Therefore, in order to perform the study more accurately and to obtain more reliable results, the genetic algorithm is used for categorizing the data of joints of the studied area. Applying this algorithm for leaving the local optimal points is an effective way. The results of clustering of the aforementioned data using the two above techniques represent two clusters in the Babakoohi Anticline. Furthermore, for validity and surveying of the results of the suggested techniques, various mathematical and statistical techniques, including ICC, Vw, VMPC, and VPMBF, are applied, which supports the similarity of the obtained results and the data clustering process in two algorithms.

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Depositional microfacies identification plays a key role in the exploration and development of oil and gas reservoirs. Asmari Formation in Oligo-Miocene is one of the most important reservoir Formations for the production and exploration of hydrocarbons in the Middle East and has a high reputation globally for a long time. In the Lorestan region, the sequences of the Asmari Formation have a carbonate-evaporate mixture of the late Miocene. The main aim of this research is to describe and interpret the different facies observations. Investigation of this sequence in one of the wells in this region has led to the identification of 17 sedimentary microfacies that belong to a homoclinal ramp-type carbonate platform. The nature and distribution of facies and environmental conditions of the Asmari Basin have undergone fundamental changes over time so that in the first part of this Formation (containing the first sequence of this Formation), the facies and their distribution pattern are similar to those of Tertiary and also others Zagros regions like Khuzestan and Fars. Still, in the second part (second sequence), there is a significant change in the Asmari basin, the most important of which is the replacement of red coral algae by a rare group of red algae with Aragonite wall. Our findings allows better characterizing and understanding which sedimentological features control the mechanical and its distribution throughout the formation.

As a consequence the leakage from karstic dam foundations and abutments, reservoir storage will be reduced. Due to the complexity of dam sites in karst, estimation of the cement to be used in the injecting boreholes and operating the sealing membrane cannot be readily done. Data mining with decision tree algorithm and searching of databases can help us to find the effective parameters in cement take. In this study, Salman Farsi Dam in Fars province in southern Iran is selected. In this article as a case study, in the left gallery at level of 853 a.m.s.l, 6 boreholes were selected. Important information such as the depth of the borehole drilling, shaft angle, and cement take at different depth intervals, hydro-mechanical behaviors (ground water flow type) gathered with Lugeon tests and were analyzed. 47.76 % of the test data indicates Lugeon ranges in impermeable to very low permeability (3 < Lu ≤ 10). Application of the technique of decision tree showed that when the angles of boreholes lie between 29 and 31.5°, depth of the borehole is less than 32.5 m, Lugeon greater than 15.5 and Hydromechanical behavior belongs to dilatation, wash out or void filling, cement take will follow the empirical Ewert (1985) theory. If the angle of the hole is higher than 31.5 degrees, flow type is void filling or linear, and Lugeon greater than 3.5, cement take and luegon number has not complied. Thus we can order the role of effective parameters on cement take as follows: angle of shaft, hydromechanical flow type, average Lugeon, and finally borehole depth. Eventually, the validity of the model is tested.

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