Mountain chains and river systems generally run North-South throughout the continent thus making for formidable barriers to East-West expansion.
The quartz is more resistant to abrasion and chemically more resistant than the feldspar. The result is that the quartz remains in the stream but the feldspar breaks down to clay or is dissolved.
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Answer
Area B will have more iron deposits than area A.
Explanation
Iron ore deposits are located in sedimentary rocks. They are formed from chemical reactions that combined iron and oxygen in marine and fresh waters. Hematite (Fe2O3) and magnetite (Fe3O4) are the two important minerals in iron oxides deposits. Iron ore are formed through chemical reactions that utilize iron and oxygen, where the gas combine with iron in dissolved form to produce Hematite and Magnetite which are deposited in the sea floor as banded iron formations. During a volcanic eruption more iron ore deposits are located near its foot
