Sedimentary Rocks Geography Quiz

Compaction is the process of reducing pore space by depositing younger sediments on top of older material. As new sediments accumulate, the weight and pressure cause the sediments to become more tightly packed, reducing the pore space between particles. This process is commonly observed in the formation of sedimentary rocks, where layers of sediment are compressed over time, resulting in the consolidation and hardening of the rock.

All of the given options can have ripples. Ripples occur on the sand beneath the waves at beaches, on underwater sandbars in streams, and on the surface of windswept dunes. Therefore, all of these options can have ripples.

All of the above options, salt, gypsum, and anhydrite, are examples of chemical sedimentary rocks. Chemical sedimentary rocks form when minerals precipitate out of solution and accumulate to form rock. In the case of salt, it forms when seawater evaporates and leaves behind salt crystals. Gypsum and anhydrite form from the evaporation of water in areas with high levels of dissolved minerals. Therefore, all three options are correct examples of chemical sedimentary rocks.

Lineation refers to the preferred orientation of elongated minerals in a rock. It can be observed as linear features such as mineral grains aligned in a specific direction or elongated minerals that are parallel to each other. Foliation, on the other hand, refers to the parallel alignment of mineral grains in a rock, creating a layered or banded appearance. Since the question specifically asks for the preferred orientation of elongated minerals, the correct answer is lineation.

Sedimentary rocks are also known as secondary rocks because they are formed from the accumulation and compaction of sediments over time. These sediments can be derived from the weathering and erosion of pre-existing rocks, as well as the remains of plants and animals. The process of lithification, which includes compaction and cementation, transforms these sediments into solid sedimentary rocks. This distinguishes them from igneous rocks, which are formed from the cooling and solidification of molten rock, and metamorphic rocks, which are formed from the transformation of existing rocks under high temperature and pressure.

If the roundness of a rock is 1, it means that the rock has a perfectly rounded shape. Therefore, the sphericity of the rock is also rounded.

Breccias and conglomerates are both types of sedimentary rocks composed of fragments. The main difference between them lies in the shape of the fragments. Breccias have angular fragments, meaning the fragments have sharp edges and corners. On the other hand, conglomerates have rounded fragments, indicating that the fragments have been rounded and smoothed by erosion and transportation. This distinction in fragment shape is the key characteristic that sets breccias and conglomerates apart from each other.

Ferruginous sandstone is a type of sandstone that contains a high concentration of iron oxide minerals, specifically hematite. Hematite is a reddish-brown mineral that gives the sandstone its characteristic color. It is formed through the deposition and cementation of sand grains along with iron-rich minerals. The presence of hematite in ferruginous sandstone gives it a distinct reddish hue and makes it a valuable resource for iron ore extraction.

Detritus is particles of rock derived from pre-existing rock through processes of weathering and erosion. A fragment of detritus is called a clast.

Marl is a type of sedimentary rock that is composed of a mixture of clay and calcium carbonate. It is formed in marine environments and is commonly associated with areas that were once covered by shallow seas. The presence of clay gives marl its characteristic fine-grained texture, while the calcium carbonate provides hardness and durability. Therefore, the correct answer is mudstone, as marl is a type of mudstone that contains a significant amount of calcium carbonate.

Chalk forms from the microscopic skeletons of phytoplankton, such as coccolithophores. When coccolithophores die, their calcium carbonate shells sink to the seafloor and eventually become chalky sediments.

The correct answer is "

The correct answer is "Both A and B" because a conglomerate can be either clastic supported or matrix supported. Clastic supported conglomerates have a framework of coarse clasts that are held together by a finer matrix material. On the other hand, matrix supported conglomerates have a framework of finer matrix material that encloses larger clasts. Therefore, both types of support can be present in conglomerates.

Chert is an example of a siliceous chemical sedimentary rock. It is composed primarily of microcrystalline quartz, which is a form of silica. Chert forms through the deposition of silica-rich materials, such as the remains of microscopic marine organisms or the precipitation of silica from groundwater. It often has a smooth and glassy appearance and can come in various colors. Chert is commonly found in layers within other sedimentary rocks and is known for its hardness and durability.

Oligomictic is also called monomictic.
Polymictic= clast represents more than one rock type.

The most important phenomenon that happens to the sediments during their transport and deposition is sorting or grading according to their size, shape and density.

Oolitic limestone is a type of limestone that is composed mainly of calcium carbonate. It is formed from the accumulation of small spherical grains called ooids, which are made up of concentric layers of calcium carbonate. Therefore, oolitic limestone is an example of calcareous rocks, as it is primarily composed of calcium carbonate.

Paragneiss is the correct answer because it is a type of gneiss that is derived from sedimentary rocks. Gneiss is a metamorphic rock that forms from the recrystallization of pre-existing rocks under high temperature and pressure. Paragneiss specifically forms from the metamorphism of sedimentary rocks, such as shale or sandstone. This process causes the minerals within the sedimentary rock to reorganize and recrystallize, resulting in the formation of paragneiss.

Arkose is the correct answer because it is a type of sandstone that forms from the mechanical weathering of granite. Granite is a coarse-grained igneous rock composed mainly of quartz, feldspar, and mica. When granite undergoes mechanical weathering, the feldspar minerals break down into smaller particles, which then become the grains in the arkose sandstone. Therefore, arkose is the most likely sandstone type to form from the weathering of granite.