Question

Placer deposits form when ____. (1 point)

Answer 1

Answer:

The answer is "heavy eroded particles settle out of moving water".

Explanation:

• Placer deposits are formed by surface weathering and ocean, river or wind action resulting in concentration of some valuable heavy resistant minerals of economic quantities. The placer can be an accumulation of valuable minerals formed by gravity separation during sedimentary processes.
• The type of placer deposits are namely, alluvial (transported by a river), colluvial (transported by gravity action), eluvial (material still at or near its point of formation), beach placers (coarse sand deposited along the edge of large water bodies) and paleo-placers (ancient buried and converted rock from an original loose mass of sediment).

• The most common placer deposits are those of gold, platinum group minerals, gemstones, pyrite, magnetite, cassiterite, wolframite, rutile, monazite and zircon.

Learn more:

• What does very poor placer mean

         brainly.com/question/11300782

• Explain how placer mining works

        brainly.com/question/10922009

Keywords:  placer, deposits, alluvial,colluvial, eluvial, beach-placer, pleao-placer

Answer 2

The correct answer is: heavy eroded particles settle out of moving water.
 Placer deposits form when heavy eroded particles settle out of moving water. Placer deposits naturally accumulate heavy, valuable minerals, which are formed by the gravitational effect during sedimentary processes. As a result, these minerals are concentrated in residual, beach and stream deposits thereby forming ore deposits.