Function Index 1 Introduction Abstract: This chapter introduces basic concepts and techniques for data mining, including a data mining process and popular data mining techniques. It also presents R and its packages, functions and task views for data mining.
Alqahtani and Azra N. TOC is composed mainly of three components: When the value of TOC is greater than 1. However, this piece of information alone is not sufficient.
Adequate convertible in situ organic carbon content is still required to generate commercially producible hydrocarbons.
The generation index of hydrocarbon is generally obtained by additional screening processes to determine the level of maturity LOM and organic matter type. Together, these processes give further assessment of the potentiality of unconventional reservoirs.
TOC significantly influences the response of the well logs collected for rock characterization and well monitoring. To further examine these influences, a Colorado School of Mines research project analyzed the influence of TOC on the acoustic and geomechanical properties of Eagle Ford Shale.
Using high-resolution log-derived reservoir data can help overcome most of the core sampling constraints and provide real-time in situ reservoir characterization. Therefore, several studies have developed new methods to estimate TOC from well logs.
The construction of a TOC log allows for rapid identification and classification of potential organic-rich zones, the determination of zones that should be sampled for specialized geochemical analysis, and the determination of the TOC vertical distribution in the formation for input to basin evaluation models.
The developed TOC quantification methods are based on measurements of gamma ray, resistivity, density, sonic, neutron, or nuclear magnetic resonance NMR tools.
Many well log-derived TOC quantification methods are indirect measurements and require empirical correlations of the log data to the geochemical data obtained from the cores.
The accuracy of empirical correlations depends on several factors including the specific characteristics of the organic-rich shale source rock. Variations in LOM for the three wells help determine the limitations of each method.
Because changes in organic content can produce significant changes in formation density, the TOC-density method attempts to correlate formation density to TOC. This method was first applied by James Schmoker and colleagues at the U. In both studies, the petrophysical system of shale was found to be composed of rock matrix minterstitial pores ipyrite p and organic matter o.
Pyrite mineral is a part of the system because of its high density and its measurable effect on formation density. Therefore, formation density can be defined as shown in Equation 1.
The delta log R approach initially developed by Quinn Passey at ExxonMobil Upstream Research uses a similar principle that involves a combination of porosity and resistivity logs. The method employs the overlaying of a porosity log in arithmetic scale and the resistivity log in logarithmic scale on an organic-lean shale interval to estimate TOC from the interval at which the two curves separate.
A sonic, density or neutron log can be used in this technique, but a sonic log is typically selected since density and neutron logs are adversely affected by the borehole conditions.
The regional background is not easy to determine, but Passey used 0. This technique requires a baseline selection that is subjective and requires some level of expertise. Heavy minerals such as pyrite can affect resistivity logs and require caution in the TOC evaluation process.
In addition, the method may not be applicable at all maturity levels.
X-ray diffraction analysis shows similar mineralogy in the Eagle Ford formation at all three well locations. A geochemical analysis indicates that TOC varies from 2.
Because of the limited amount of core data available for this study, it was not possible to find a good correlation between the volume fraction of pyrite and organic matter for the Eagle Ford.
Therefore, the analysis used the correlation of pyrite and organic matter obtained with the TOC-density method.
Because the three wells were drilled using oil-based fluid and their image logs indicated no borehole condition issues, the computation of TOC from the density log became straight forward.
From the plot, the computed organic content of the three wells appears to be in reasonable agreement with that obtained from core samples. To apply this method, compressional transit time and resistivity logs were plotted on the same track, and then the resistivity logarithmic scale was adjusted to get both curves overlain over a significant depth range of organic-lean interval.
The baselines of resistivity and transit-time logs are chosen as the average values for the identified interval. Once the baseline is established, organic-rich intervals are identified by separation and non-parallelism of the two curves.
The LOM was obtained from Figure 2.
Advantages And Limitations The availability and quality of log and core data are two major constraints that influence the evaluation of TOC quantification methods. Each of the methods used in the Eagle Ford study has advantages and limitations. The average percentage of absolute difference for each method compared to core-derived TOC was 0.
It is difficult to draw a solid conclusion on which TOC quantification method represents a better fit for the Eagle Ford Shale because of the limited number of core samples used in this study. As more Eagle Ford data become available, it may be possible to obtain a better correlation.
Alqahtani is a petroleum engineer for Saudi Aramco Oil Company. He holds a B.Total organic carbon (TOC) is determined by treating an aliquot of dried sample with sufficient phosphoric acid () to remove inorganic carbon prior to instrument analysis.
Consider, for example, the case when TCO analysis applies to a potential IT system acquisition. IT TCO comparisons from publishing analysts tend to focus narrowly on costs due to purchase, maintenance, and straightforward operating expenses.
Here the emphasis is on comparing different vendor solutions fairly. Related articles.
Case study - Tin plating wastewater treatment Feb. 15, The Client The Client is a steel industry based in the Middle East producing tinplates for food cans. Introduction .. The Impact of Mission, Vision, and Culture on Profits and Strategic Planning. TOC and JIT Sale and Inman have conducted a survey of 45 Indian companies comparing the performance and the change in performance of companies reporting TOC adoption.5 TOC and Six Sigma Ehie and Sheu propose an integrated TOC/Six Sigma framework to combine the benefits of Six Sigma and TOC from a sample of PeCOD® Case Study #10 Event detection comparison of PeCOD, TOC, UV & SUVA.
2. The L PeCOD® Analyzer was used alongside TOC, UV, and SUVA over a four-month period, Figure 2: peCOD, TOC, UV, and SUVA results from a Texas WTP for filter 4 effluent, before, during, and after ozonation going offline.