List of top Geology Questions asked in IIT JAM GG

A coal seam occurs in a stratigraphic sequence as shown in the figure. If a vertical borehole is drilled at location B, the coal seam will be intersected at a depth (in m) of ........ 

From the data shown in the table, the weighted mean size (in micrometer, correct to two decimal places) of the sediment population is ............ 
\[ \begin{array}{|c|c|} \hline \text{Grain Size (micrometer)} & \text{Dry Sediment Weight (in gram)} \\ \hline 4 & 50 \\ 20 & 75 \\ 40 & 125 \\ 60 & 50 \\ \hline \end{array} \]

Consider the schematic isobaric T-X phase diagram in the binary forsterite (Fo)-fayalite (Fa) chemical system. If there is equilibrium crystallization of melt (L), the wt.% of olivine crystallized from a melt of composition "a" at a temperature T2 is ......... 

Consider a schematic isobaric ternary phase diagram A-B-C, shown below, which is contoured with isopleths of liquidus temperatures (in \(^\circ C\)), reveals crystallization behaviour of melt (L) of different compositions during cooling. When a melt of composition "a" lies at a temperature of 1800\(^\circ C\), the variance (or degree of freedom) of the magmatic system is ........ 

A set of sedimentary rocks A, B, and C are affected by a fault F-F. The amount of vertical throw (in m) along the fault is ............ 

In the given profile section, P, Q, R, S, and T are sedimentary rocks. Identify the type of unconformity in the sedimentary sequence. 

Match the seismic discontinuity in Group I with their occurrence in Earth's interior in Group II. 
\[\begin{array}{|l|l|} \hline \textbf{Group I} & \textbf{Group II} \\ \hline \text{P. Conrad} & \text{1. Between lower mantle and outer core} \\ \hline \text{Q. Mohorovičić} & \text{2. Between crust and upper mantle} \\ \hline \text{R. Gutenberg} & \text{3. Between inner and outer core} \\ \hline \text{S. Lehmann} & \text{4. Between lower and upper crust} \\ \hline \end{array}\]

Identify the fold in the given figure, where T₀ and Tα represent the axial plane thicknesses at the hinge and limb, respectively. 

Match the landform in Group I with the corresponding geological process in Group II. 
\[\begin{array}{|l|l|} \hline \textbf{Group I} & \textbf{Group II} \\ \hline \text{P. Cinder Cone} & \text{1. Eolian} \\ \hline \text{Q. Ox-bow lake} & \text{2. Glacial} \\ \hline \text{R. Draas} & \text{3. Volcanic} \\ \hline \text{S. Drumlin} & \text{4. Fluvial} \\ \hline \end{array}\]

Match the twinning in Group I with the corresponding mineral in Group II. 
\[\begin{array}{|c|c|} \hline \textbf{Group I} & \textbf{Group II} \\ \text{P. Cross-hatched} & \text{1. Plagioclase} \\ \hline \text{Q. Carlsbad} & \text{2. Microcline} \\ \hline \text{R. Polysynthetic} & \text{3. Sanidine} \\ \hline \text{S. Brazil} & \text{4. Quartz} \\ \hline \end{array}\]