List of top Geology Questions asked in GATE Geology and Geophysics

In the isochemical phase diagram shown below, the curved arrow represents the P-T path. The variance at peak metamorphism is _. 


 

Which characteristic feature(s) best explain(s) the HIMU mantle reservoir?
Choose the explanation(s) for negative Eu anomalies in upper crustal rocks like granite and granodiorite.

The units A to H marked on the figure represent different rock formations. Select the option that describes the chronological sequence from old to young. 


 

In a hypothetical scenario, the element Y has 4 stable isotopes \(^{197}{Y}\), \(^{198}{Y}\), \(^{199}{Y}\), and \(^{200}{Y}\). The isotope \(^{199}{Y}\) is radiogenic and is formed by \(\beta^-\)-decay of the isotope \(^{199}{X}\) of the element X with a half-life of 3.51 billion years. An igneous rock, which has behaved as a closed system, has three different minerals P, Q, and R, which crystallized from the same magma 2 billion years ago, with initial X/Y ratios of 1.75, 2.05, and 0.75, respectively. Which one of the following statements is true for the ratio \(^{199}{Y}/^{200}{Y}\) in this igneous rock in the present day?
A particular Index of Alteration (IA) is defined as the molar concentration ratio (expressed as weight percentage) of fluid immobile element(s) to fluid mobile element(s) and is expressed by \(100 \times \left(\frac{[Al_2O_3]}{[Al_2O_3] + [Na_2O] + [K_2O]}\right)\). For chemical weathering of silicate rocks, which one of the following statements is correct?
In a hypothetical rock, the Kd values of element E in minerals M1, M2, and M3 are 1.5, 1.0, and 0.5, respectively. The modal abundances of M1, M2, and M3 are 10%, 40%, and 50%, respectively. The bulk partition coefficient of element E in this rock is ________
Compared to Fe, Mg, and Ca, the content of K is extremely low in igneous clinopyroxene. Which of the following CANNOT explain its low abundance?
Which of the following rocks is/are characteristic of fossil subduction zones?
Which of the following statements is/are NOT correct for stratigraphy of the Himalaya?

Which one of the following statements correctly describes the features in the geological map? 


 

Shown below is a schematic plot of \(\varepsilon_{Nd}\) (deviation of \(^{143}Nd/^{144}Nd\) in a sample relative to CHUR) versus time. The two solid lines represent the evolution curves for the depleted mantle reservoir and the continental crust. Which one of the four dashed lines, marked 1, 2, 3, and 4, represents the evolution of the CHUR? 


 

During a geochemical exploration survey in a hilly terrain, Cu concentration of stream sediments from a third order basin outlet was measured to be 3000 ppm. Considering a catchment area of 10 km\(^2\) and a Cu background value of 200 ppm, which one of the following options is the productivity of this catchment for Cu?
Which one of the following statements explains why elements Li, Be, and B have low cosmic abundance?

Consider two intersecting, north-easterly striking and south-easterly dipping dikes Y1 and Y2, which are exposed on an east-west trending vertical wall of a granite (X) quarry as shown below. 

The angle that the dikes make with the horizontal on the quarry wall is

Which of the following time boundaries correspond(s) to major mass extinction events?
A type of fold which is relatively sharp and angular at its synformal and antiformal hinges is known as:
Which one of the following expressions represents porosity of a rock?