Geologic cycle of soil formation — choose the correct chronological sequence of processes leading to soil and rock recycling at the Earth's surface:

Difficulty: Easy

Correct Answer: Weathering → transportation → deposition → upheaval

Explanation:


Introduction / Context:
The geologic cycle describes how rocks break down into soils, get transported and deposited, and then are uplifted and exposed again. Recognizing the typical sequence helps civil engineers interpret soil profiles, depositional environments, and anticipated geotechnical properties such as density, grading, and fabric.


Given Data / Assumptions:

  • Cycle is simplified to the dominant surface processes.
  • Weathering broadly includes physical and chemical breakdown of rock.
  • Transportation occurs via water, wind, or ice; deposition forms sediments; uplift (upheaval) exposes them again.


Concept / Approach:

Rock first undergoes weathering near the surface, producing soil and detritus. Agents then transport particles to new locations where they are deposited as layers with characteristic sorting and stratification. Tectonic forces may later uplift these deposits, exposing them to renewed weathering and continuing the cycle. This idealized sequence matches many surficial geology observations relevant to siting foundations and earthworks.


Step-by-Step Solution:

Start with intact rock at or near surface.Weathering reduces rock to soil and fragments.Transportation moves the material downslope or downstream.Deposition forms sedimentary layers or residual accumulations.Upheaval/uplift exposes deposits to future weathering, closing the loop.


Verification / Alternative check:

Regional geomorphology and stratigraphy commonly show weathered bedrock overlain by transported and deposited sediments, later tilted or uplifted by tectonics.


Why Other Options Are Wrong:

Sequences starting with upheaval or transportation before weathering invert the causal order; deposition cannot precede weathering of source rock.


Common Pitfalls:

Assuming a single pathway; in reality, local cycles may skip steps or repeat sub-steps, but the canonical order remains as given.


Final Answer:

Weathering → transportation → deposition → upheaval

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