Jeopardy: The Geology & Melting Edition
Formed by the cooling and solidification of molten rock, this primary category includes intrusive varieties like granite and extrusive ones like basalt.
igenous rock
A clastic sedimentary rock composed predominantly of rounded, gravel-sized or larger rock fragments is classified.
colmargrate.
Which of the following best describes an intrusive (plutonic) igneous environment?
Magma cools slowly beneath the Earth's surface, allowing large mineral crystals to grow
Which of the following parent rocks transforms into marble during metamorphism?
limestone
Which of the following processes is a classic example of physical (mechanical) weathering driven by the expansion of freezing water in rock fractures?
frost wedgeing
This category of rock is characterized by visible layers or strata and is created by the compaction and cementation of weathered mineral debris or organic remains.
sedimentary rock
Which of the following best distinguishes weathering from erosion?
weathring is the in place and chemical break down of rock whearas erosion is the physical removal and transport of those whearthed materials.
An igneous rock with a phaneritic texture is characterized by which of the following features?
Mineral crystals that are large enough to be seen with the unaided eye due to slow cooling.
Which characteristic best defines contact metamorphism compared to regional metamorphism?
It is driven primarily by heat from a rising magma intrusion acting on the local country rock without intense directed pressure.
The process by which atmospheric oxygen reacts with iron-bearing minerals in a rock, creating a reddish-brown rust coating (such as hematite or limonite), is known as:
Oxidation
Marble and slate belong to this category of rocks, which are transformed from older parent rocks through intense heat and directed pressure without fully melting.
metamorphic
The precipitation of mineral cement from groundwater filling the remaining pore spaces.
How do felsic igneous rocks typically differ from mafic igneous rocks in terms of chemical composition and color?
Biological absorption of sediment by deep-dwelling microorganisms.
What primary physical condition causes platy or elongated minerals in a metamorphic rock to align in parallel bands, producing foliation?
Directed differential stress (unequal pressure) pushing perpendicular to the preferred mineral orientation.
Why does breaking a large rock into smaller pieces significantly increase the overall rate of chemical weathering?
Common beneath divergent boundaries and mantle plumes, this melting mechanism happens when hot mantle rock moves upward, reducing the surrounding confining pressure.
decompression melting
Which of the following rocks is classified as a chemical sedimentary rock formed by the precipitation of minerals from evaporating water?
Rock salt / Halite
What causes the distinctive "vesicular" texture seen in volcanic rocks like pumice or scoria?
Gas bubbles trapped in cooling lava as it solidifies at or near the Earth's surface
When shale undergoes low-grade regional metamorphism, what fine-grained, foliated rock does it typically form?
Which scenario describes a combined process of biological and physical weathering?
Operating primarily at subduction zones, this melting process lowers a rock's melting temperature by introducing water and other volatile compounds from subducted oceanic crust.
flux melting.
Cross-bedding within a sandstone layer is most useful to geologists for determining what aspect of the depositional environment?
The direction and movement of ancient paleocurrents like wind or flowing water.
What does a porphyritic texture (large crystals called phenocrysts set in a finer-grained groundmass) indicate about a rock's cooling history?
The magma experienced a two-stage cooling process—slow cooling at depth followed by faster cooling closer to the surface or during an eruption.
Which textural description best fits non-foliated metamorphic rocks like quartzite and marble?
A granoblastic mosaic of tightly interlocking, equidimensional mineral crystals.
How does running water primarily erode a stream or river bed?
By hydraulic action (the force of moving water) and abrasion as suspended sediment scrapes against the channel.