Physio-Mechanical Properties and Petrographic Analysis of NikanaiGhar Limestone KPK, Pakistan

Petrographic, physical, and mechanical assessment investigation of NikanaiGhar limestone aggregate exposed in the Lower Dir area of Malakand Division, Pakistan, were conducted to evaluate and investigate its potential for use as a construction material for engineering projects. Different geotechnical tests and petrographic analyses were performed to evaluate its potential for construction purposes. Geotechnical tests include unconfined compressive strength, ultimate tensile strength test, specific gravity, share strength, porosity, and water absorption. The evaluated physical attributes were compared to standard specifications to determine their suitability as a construction material. Petrographic investigation indicates mainly two types of stones. Stylolitic spar stone and Spar stone are metamorphosed equivalent limestones and are not prone to alkali-silica reactivity. Mutual relationships between physical parameters have been described by simple regression analysis. Significant direct correlation of specific gravity with ultimate tensile strength and uniaxial compressive strength was noted. However, negative trends of Porosity with ultimate tensile strength and uniaxial compressive strength were observed which is in accordance with standard. The analysis revealed that the limestones of NikanaiGhar Formation fall within the standard specification limits and can be used as aggregates for the indigenous construction industry.

Depositional facies and reservoir characteristics of the Early Cretaceous Lower Goru Formation,Lower Indus Basin Pakistan:Integration of petrographic and gamma-ray log analysis

The sand intervals of the Early Cretaceous Lower Goru Formation are a conventional reservoir,generally distributed in the Middle and Lower Indus Basin of Pakistan.Lithostratigraphically formation is classified into two parts;the upper parts are predominantly composed of shale,siltstone,and thin layers of alternate shale and sandstone,while the lower parts are composed of sandstone with interlayering of shale and limestone.The sandstone of the Lower Goru Formation has been further divided into A,B,C,and D sand intervals based on reservoir quality.Detailed depositional facies and reservoir characteristics are essential for the evaluation of hydrocarbon exploration and development.This paper aims to evaluate the depositional environment and reservoir characterization of the siliciclastic reservoir of the Early Cretaceous Lower Goru Formation by integrating the gamma-ray log patterns and petrographic analysis and scanning electron microscopic(SEM)analysis.Petrographic characterization of the sand intervals and Gamma-ray log signatures were used for the interpretation of the depositional environment of the reservoir intervals.Petrographic analysis reveals that the sandstone of the Lower Goru Formation is fine-to medium-grained,well-sorted,arkose or feldspathic arenite.Primary intergranular macroporosity,secondary intragranular macropores,and Intercrystalline micropores were identified within the sandstone by the SEM analysis.The diagenetic analysis suggests that the sandstone possesses high porosity,low permeability,and has undergone significant alterations such as compaction,quartz cementation,feldspar dissolution,and clay minerals alteration.Five electrofacies are interpreted based on gamma-ray log patterns including(1)funnel shape(FA);(2)bell shape(FB);(3)cylindrical shape(FC);(4)bow shape(FD);and(5)serrated shape(FE)patterns.The interpreted facies results reveal shoreface environment for A-sand,Tidal flat for B-sand,mixed tidal flat for C sand,Tide dominated mixed for D-sand,and transgressive shelf for Esand.The present study will be helpful for the assessment of the reservoir quality of the Early Cretaceous Lower Goru Formation for further exploration and development in the Indus Basin of Pakistan.

Formation of Ca_3SiO_5 prepared by electric and microwave burning

A new method of sintering Ca3SiO5 by the combination of conventional and microwave heating methods was studied. The influence of transitional metal oxides such as Fe2O3, Cr2O3, MnO2, and V2O5 used as the additive of microwave absorption on the microwave-promoted burning of Ca3SiO5 was investigated. The experimental results indicate that the new burning technique is capable of promoting the sintering of Ca3SiO5. At 1200-1300℃ in an electric furnace, Ca3SiO5 can be obtained only when the sample is heated in a microwave for 110-240 s, and the free lime content is below 40wt%. Based on the experiments, Fe2O3, Cr2O3, MnO2, and V2O5 can enhance microwave sintering. Amongst them, Cr2O3 is the most effective. The characteristic of the X-ray diffraction peaks of Ca3SiO5 is similar to those of standard Ca3SiO5, but the peaks are wider.

Slag Melting Characteristic of Slag Forming and Slag Splashing for BOF Less Slag Smelting

The slag melting characteristic of slag forming and slag splashing for 300 t BOF less slag process is researched by combining the methods of the slag chemical composition, the melting point determination and the petrographic analysis. The results show that the melting point of final slag for less slag smelting is 20 ~C lower than that for conventional smelting. According to results of the petrographic analysis, the C3S （3CaO ~ SiO2） and C2S （2CaO · SiO2） content for less slag smelting are lower than those for conventional smelting, while the RO （FeO, MgO, MnO, etc） phase and C4AF （4CaO · Al2O3· Fe2O3） phase are higher than those for conventional smelting. According to results of the chemical analysis, the （CaO） content and slag basicity for less slag smelting are higher than those for conventional smelting, while （FeO） and （MgO） content in slag for less slag smelting are almost equal to those for conventional smelting. The reason why slag melting point for less slag smelting is lower than that for con- ventional smelting is that the quantity of added fluorite for less slag smelting is more than that for conventional smel- ting. According tO the analysis results the slag melting point is determined by the C3S, C2S, RO phase and C4AF content. According to the results of slag melting characteristic before and after slag splashing for less slag smelting, the present adjusting slag process has little effect. It is important to adjust the composition of BOF final slag. The （FeO） content in slag is to be reduced at the slag splashing and adjusting slag process for less slag smelting.