WEATHERING — Outcomes of the weathering process Which of the following correctly describes possible results of weathering acting on rocks at or near Earth's surface?

Introduction / Context:
Weathering is the in-place alteration and disintegration of rocks, setting the stage for soil formation and erosion. It includes both chemical and mechanical processes, each producing different outcomes at the rock surface.

Given Data / Assumptions:

• Options refer to loss, gain, and physical breakup.
• Weathering is distinct from erosion (transport), but products can be moved later.
• Multiple outcomes may occur simultaneously at a site.

Concept / Approach:
Chemical weathering can remove components (leaching), add new materials (through precipitation or secondary mineral formation), and transform minerals. Physical (mechanical) weathering breaks rocks into smaller pieces without changing mineral chemistry. Therefore, a comprehensive answer must include all these possibilities.

Step-by-Step Solution:
Recognize chemical removal: loss of ions via solutions → leaching.Recognize chemical addition: secondary minerals or precipitates can accumulate in horizons (illuviation).Recognize physical disintegration: fragmentation due to thermal stress, frost action, unloading, or biological activity without chemical change.Hence, all listed outcomes are valid.

Verification / Alternative check:
Field profiles show eluviation (export) and illuviation (import) zones, and outcrops exhibit exfoliation and block disintegration—all components of weathering outcomes.

Why Other Options Are Wrong:
Any single option alone is incomplete; weathering includes diverse outcomes.“Only chemical alteration without any physical change” ignores well-documented mechanical processes.

Common Pitfalls:
Equating weathering solely with either chemical decay or mechanical breakup; in reality, both operate together.

Final Answer:
All of the above