Final answer:
Rocks from Peru and Brazil are likely different types because they formed in different ways, like igneous, sedimentary, or metamorphic rocks, despite containing similar minerals.
Step-by-step explanation:
The rocks from Peru and Brazil are likely to be different types because they formed in different ways, despite both being comprised of rock material. This aligns with option 4: Different types because they formed in different ways, as classified by geologists.
Geologists classify rocks into three basic categories based on their formation processes: igneous, sedimentary, and metamorphic. Igneous rocks are formed from the cooling and solidification of magma or lava. Sedimentary rocks are created from the accumulation and cementation of mineral and organic particles, whereas metamorphic rocks arise from the transformation of existing rocks due to heat and pressure. The composition of minerals in these rocks can be an indication of their origins.
Even if the rocks from Peru and Brazil contain some identical minerals, they can still be entirely different types of rocks depending on how they formed. For example, granite (igneous), arkose sandstone (sedimentary), and gneiss (metamorphic) may contain the same minerals but are classified differently due to their distinct formation processes. Geological factors, such as tectonic settings and environmental conditions, play a crucial role in determining how these rocks are formed.