Kerogen is an intermediate compound in the process of petroleum formation in a sedimentary basin. This is typically classified into four categories (Type-I, Type-II, Type-III and Type-IV) based on the relative amount of carbon (C), hydrogen (H), oxygen (O) present in it (shown in the figure below). Which of the following is the X-axis and Y-axis, respectively?
Kerogen is an intermediate compound in the process of petroleum formation in a sedimentary basin. This is typically classified into four categories (Type-I, Type-II, Type-III and Type-IV) based on the relative amount of carbon (C), hydrogen (H), oxygen (O) present in it (shown in the figure below). Which of the following is the X-axis and Y-axis, respectively?
Show Hint
- H:C ratio and O:C ratio
- O:C ratio and H:C ratio
- C:H ratio and C:O ratio
- C:O ratio and C:H ratio
The Correct Option is B
Solution and Explanation
- On the X-axis, the oxygen-to-carbon (O:C) atomic ratio is plotted. This ratio reflects the oxygen content in the organic matter. As kerogen matures, the O:C ratio decreases due to loss of oxygen-containing compounds (e.g., CO$_2$, H$_2$O).
- On the Y-axis, the hydrogen-to-carbon (H:C) atomic ratio is plotted. This ratio reflects the hydrogen content in the organic matter. A higher H:C ratio is associated with oil-prone kerogen (Type I), while lower H:C ratios are linked to gas-prone kerogen (Type III/IV).
- From the figure, we can clearly see Type-I kerogen has high H:C and low O:C values, making it oil-prone. Type-III and Type-IV kerogens have lower H:C ratios and relatively higher O:C values, indicating gas-prone or inert material.
- Therefore, the correct labeling is: \[ \text{X-axis = O:C ratio, \quad Y-axis = H:C ratio} \]
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Identify the option that has the most appropriate sequence such that a coherent paragraph is formed:
Statement:
P. At once, without thinking much, people rushed towards the city in hordes with the sole aim of grabbing as much gold as they could.
Q. However, little did they realize about the impending hardships they would have to face on their way to the city: miles of mud, unfriendly forests, hungry beasts, and inimical local lords—all of which would reduce their chances of getting gold to almost zero.
R. All of them thought that easily they could lay their hands on gold and become wealthy overnight.
S. About a hundred years ago, the news that gold had been discovered in Kolar spread like wildfire and the whole State was in raptures.
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\[ \begin{aligned} N & = \text{Initial (original) oil in place, stb} \\ G & = \text{Initial volume of gas cap, scf} \\ m & = \text{Ratio of initial volume of gas cap to volume of oil initial in place, rb/rb} \\ S_{wi} & = \text{Initial water saturation} \\ S_{oi} & = \text{Initial oil saturation} \\ B_{oi} & = \text{Initial oil formation volume factor, rb/stb} \\ B_{gi} & = \text{Initial gas formation volume factor, rb/scf} \end{aligned} \]
The total pore volume (in rb) of the reservoir is:
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