UGC NET Earth Systems & Environmental Geoscience: practice questions

1 · Origin and evolution of the earth and its spheres · medium

What do banded iron formations record?

1. Human iron smelting in the Bronze Age across Europe and Asia
2. Oxygen from early photosynthesis reacting with dissolved iron in oceans
3. Ice ages caused by Milankovitch cycles in the last million years
4. Volcanic eruptions on the Moon during the giant impact that formed the Moon itself

2 · Origin and evolution of the earth and its spheres · hard

Which process best explains the formation of the Moon?

1. Fission of a fast-spinning earth during the Great Oxidation Event
2. A giant impact of a Mars-sized body with the proto-earth
3. Capture of a passing asteroid by the earth's gravity 1 billion years ago
4. Condensation from the solar nebula far from the earth, followed by migration

3 · Minerals and rocks: igneous, sedimentary, metamorphic · hard

In Bowen's reaction series, which mineral crystallises last as magma cools?

1. Calcium plagioclase
2. Quartz
3. Olivine
4. Pyroxene

4 · Weathering and soil formation from parent material · medium

Hydrolysis of potassium feldspar mainly produces:

1. Quartz and calcite crystals with sodium
2. Olivine and pyroxene
3. Kaolinite clay, K+ and dissolved silica
4. Haematite and gypsum

5 · Geomorphic processes and landforms · medium

An oxbow lake forms when:

1. A glacier retreats from a cirque
2. A sand bar closes a bay
3. A river meander is cut off
4. A sinkhole fills with rain

6 · Geomorphic processes and landforms · hard

A first-order and a second-order stream join. What is the Strahler order downstream?

1. First order
2. Third order
3. Second order
4. Fourth order

7 · Mineral resources and the environmental impact of extraction · hard

India's District Mineral Foundations, created by a 2015 amendment to mining law, aim to:

1. Export minerals duty-free
2. Nationalise all private mines
3. Ban all mining in forest areas across the country
4. Use mining revenues for communities affected by mining

8 · Natural hazards: volcanoes, landslides, tsunamis · medium

Which magma type produces explosive eruptions and stratovolcanoes?

1. Seawater mixed with sand
2. Magma with no dissolved gas
3. Low-viscosity, gas-poor basaltic magma
4. Viscous, silica- and gas-rich magma

9 · Paleoclimate records: ice cores, sediments, tree rings · medium

Air bubbles in ice cores directly record past:

1. Ocean salinity
2. Rock types
3. Atmospheric CO2 and methane
4. Earthquake magnitudes

10 · Paleoclimate records: ice cores, sediments, tree rings · hard

During the Last Glacial Maximum (~21,000 years ago), sea level was about:

1. The same as today
2. 120 m lower than today
3. 1,200 m lower than today
4. 12 m higher than today