NDA (II) 2022 General Ability Test · Question 96 of 150

Correct — D, paleogeography. Split the word and the definition falls out — 'paleo' means ancient and 'geography' means the description of the Earth's surface, so paleogeography is the reconstruction of the Earth's geography in past ages. That is exactly what the stem describes, the making and reading of historical maps of where land, sea, mountains and shorelines stood at a given point in geologic time. Familiar reconstructions of Pangaea and Gondwana are paleogeographic maps.

• (a)paleoclimatology — Paleoclimatology reconstructs past climates — temperature, rainfall, ice cover — from evidence such as ice cores, tree rings and pollen, not maps of land and sea.
• (b)paleogeomorphology — The 'geomorph' root narrows it to ancient landforms and relict or buried surfaces, which is a sub-field rather than the whole-Earth mapping the question describes.
• (c)paleolithology — The 'litho' root points to rocks; it is not the standard name for reconstructing the past distribution of land and sea, and the term also invites confusion with the Palaeolithic age of prehistory.

Paleogeography reconstructs how the Earth's surface was arranged at successive points in the geological past. The evidence comes from the rock record — the type and setting of sedimentary layers, the fossils they contain, and palaeomagnetic signals frozen into rocks that record the latitude and orientation at which they formed. Assembled across a time scale, these give maps of drifting continents, vanished seas and former mountain belts.

Every option shares the 'paleo' prefix, so the whole item rests on reading the second half of the word. Match the root to the subject — climate for climatology, landforms for geomorphology, rocks for lithology, and the description of the Earth's surface for geography. Only the last one matches 'historical maps of the Earth'.

• Paleogeography maps the past distribution of continents, oceans, shorelines and mountain belts.
• Its evidence includes sedimentary facies, fossils and palaeomagnetic data preserved in rocks.
• Palaeomagnetic results from Indian rocks show the Indian landmass drifted northward from Gondwana before colliding with Asia.
• Paleoclimatology is the parallel field for past climates, reconstructed from ice cores, tree rings and pollen records.

• Choosing paleoclimatology because both fields reconstruct the deep past — one maps places, the other reconstructs climate.
• Confusing paleogeography with the Palaeolithic period of human prehistory.

A terminology item solved by root-splitting; the second half of the word decides the answer.

• practice — not a real PYQ

  The reconstruction of past climates from ice cores, tree rings and pollen records is called

  • (a)paleogeography
  • (b)paleoclimatology
  • (c)paleobotany
  • (d)paleontology

  Answer(b) paleoclimatology — paleogeography maps past land and sea instead.

• practice — not a real PYQ

  Maps showing the assembled supercontinent Pangaea are best described as

  • (a)topographic maps
  • (b)paleogeographic maps
  • (c)cadastral maps
  • (d)thematic weather maps

  Answer(b) paleogeographic maps — they show the Earth's surface as it was arranged in a past geological age.