1.
Erosion is the:
Correct Answer
A. Movement of weathered material from its source site.
Explanation
Erosion refers to the process of movement of weathered material from its source site. This can include the transportation of rocks, soil, and other debris by natural forces such as wind, water, or ice. It is a natural process that occurs over time and can result in the reshaping of landscapes and the formation of new landforms. Erosion plays a significant role in shaping the Earth's surface and can have both positive and negative impacts on the environment.
2.
If all of the grains in a sedimentary rock are about the same size, shape, and composition, the rock can be characterized as:
Correct Answer
D. Well sorted.
Explanation
If all of the grains in a sedimentary rock are about the same size, shape, and composition, it indicates that the rock is well sorted. Well sorted sedimentary rocks have grains that are similar in size, shape, and composition because they have undergone consistent transportation and sorting processes. This suggests that the sediment was deposited in an environment with consistent energy levels, such as a beach or river, where the grains were able to settle and arrange themselves in a uniform manner.
3.
Sediments are classified as:
Correct Answer
C. Detrital and chemical.
Explanation
The correct answer is detrital and chemical because sediments can be classified into two main types based on their origin and composition. Detrital sediments are made up of weathered rock fragments and are transported by erosion and deposition processes. Chemical sediments, on the other hand, are formed by the precipitation of minerals from solution. This classification helps to differentiate between sediments that are derived from the breakdown of pre-existing rocks and those that are formed through chemical processes.
4.
Detrital sediments and rocks are classified by:
Correct Answer
B. Grain size.
Explanation
Detrital sediments and rocks are classified by grain size because the size of the grains can provide information about the energy of the environment in which they were deposited. Coarser grains typically indicate higher energy environments such as rivers or beaches, while finer grains suggest lower energy environments like lakes or deep ocean basins. Grain size can also affect the properties and behavior of the sediment or rock, such as permeability and porosity. Therefore, grain size is an important factor in classifying and understanding detrital sediments and rocks.
5.
Chemical sedimentary rocks generally have an interlocking grain texture called
Correct Answer
C. Crystalline
Explanation
Chemical sedimentary rocks generally have a crystalline grain texture. This means that the grains of these rocks are tightly interlocked, forming a solid and cohesive structure. Unlike clastic sedimentary rocks, which are made up of fragments of pre-existing rocks, chemical sedimentary rocks are formed from the precipitation of minerals from water solutions. This process allows the minerals to crystallize and grow, resulting in a crystalline texture.
6.
The properties used to describe detrital sediment are:
Correct Answer
D. All answers apply
Explanation
The properties used to describe detrital sediment are size, sorting, and rounding. Size refers to the diameter of the sediment particles, sorting refers to the uniformity in size of the particles within a sediment sample, and rounding refers to the shape of the particles. All of these properties are important in characterizing detrital sediment and understanding its origin and transport history.
7.
The designation of sediment grain size, from largest to smallest, is
Correct Answer
B. Gravel, sand, silt, clay
Explanation
The correct answer is gravel, sand, silt, clay. This is because sediment grain size is typically categorized from largest to smallest. Gravel is the largest grain size, followed by sand, silt, and clay, which is the smallest grain size.
8.
Sorting is a result of:
Correct Answer
C. Selective transport and deposition
Explanation
Sorting refers to the process of separating and arranging sediment particles based on their size and density. It occurs when sediment is transported and deposited by natural agents such as wind, water, or ice. However, selective transport and deposition play a crucial role in sorting. Sediment particles of different sizes and densities are selectively transported and deposited by these agents, leading to the separation and arrangement of particles based on their characteristics. Therefore, the correct answer is selective transport and deposition.
9.
Graded bedding forms when:
Correct Answer
C. Turbidity currents deposit first coarse sediment then fine sediment
Explanation
Graded bedding forms when turbidity currents deposit first coarse sediment then fine sediment. Turbidity currents are fast-moving currents that carry a mixture of sediment and water down a slope. As the turbidity current slows down, it begins to deposit the sediment it is carrying. The coarse sediment, which is heavier, settles first and forms a layer at the bottom. Then, the finer sediment, which is lighter, settles on top of the coarse sediment. This process creates a distinct layering pattern called graded bedding, with the coarse sediment at the bottom and the fine sediment on top.
10.
The presence of mud cracks in a sedimentary rock is a sign that the rock was deposited
Correct Answer
A. in a region that was drying
Explanation
The presence of mud cracks in a sedimentary rock indicates that the rock was deposited in a region that was drying. Mud cracks form when wet mud dries out and contracts, causing it to crack and form distinct patterns on the surface. This process typically occurs in environments with fluctuating water levels, such as drying lakes or riverbeds. Therefore, the presence of mud cracks suggests that the rock was formed in a region where water was present but gradually drying up.
11.
Oolithic limestone contains small round fossils the make the rock appear bumpy
Correct Answer
A. True
Explanation
Oolithic limestone is a type of limestone that is composed of small spherical grains called ooids. These ooids are formed by the precipitation of calcium carbonate around a nucleus, such as a shell fragment or sand grain, in shallow marine environments. The accumulation of these ooids gives the limestone a bumpy or grainy appearance. Therefore, the statement that oolithic limestone contains small round fossils that make the rock appear bumpy is true.
12.
Which type of rock is formed when marine organisms convert the calcium and carbonate ions dissolved in seawater into shells and other hard body parts?
Correct Answer
C. Evaporate
Explanation
Evaporate is the correct answer because it is the type of rock formed when marine organisms convert calcium and carbonate ions dissolved in seawater into shells and other hard body parts. Evaporate rocks are formed through the process of evaporation, where water containing dissolved minerals evaporates, leaving behind minerals that eventually form rock structures. This process is commonly seen in areas with high evaporation rates, such as salt flats or shallow marine environments.
13.
An example of a carbonate sedimentary rock is
Correct Answer
D. Limestone
Explanation
Limestone is an example of a carbonate sedimentary rock because it is primarily composed of the mineral calcite, which is a carbonate mineral. It forms from the accumulation and compaction of organic remains, such as shells and coral, or from the precipitation of calcium carbonate from water. Limestone is often found in marine environments and is used as a building material and in the production of cement.
14.
Lithification, the conversion of sediment to sedimentary rock, is a result of
Correct Answer
C. Compaction and cementation.
Explanation
Lithification is the process by which loose sediment is transformed into solid sedimentary rock. This process involves two main steps: compaction and cementation. Compaction occurs when the weight of overlying sediment compresses the grains together, reducing the pore spaces between them. Cementation then takes place as minerals precipitate and fill in these pore spaces, binding the sediment grains together and solidifying the rock. Therefore, the correct answer is compaction and cementation.
15.
Fossils can be preserved with their original composition like bones or hair.
Correct Answer
A. True
Explanation
Fossils can indeed be preserved with their original composition like bones or hair. This is possible through a process called mineralization, where the organic material of the fossil is replaced by minerals such as silica or calcium carbonate. This preserves the shape and structure of the original material, allowing scientists to study and analyze it. Additionally, in some cases, the fossilization process can preserve soft tissues or even DNA, providing valuable insights into the ancient organisms.
16.
Which of the following is not a fossil?
Correct Answer
D. The skeleton of your pet fish
Explanation
The skeleton of your pet fish is not a fossil because fossils are the remains or traces of ancient organisms that have been preserved in rocks or other geological materials over long periods of time. The skeleton of your pet fish is a recent organism and has not undergone the process of fossilization.
17.
The important difference in the clastic sedimentary rocks types -- conglomerate, sandstone, shale and siltstone -- is:
Correct Answer
C. Particle size
Explanation
The important difference in the clastic sedimentary rock types is the particle size. Conglomerate consists of large, rounded particles, sandstone consists of medium-sized particles, shale consists of fine particles, and siltstone consists of even finer particles. The particle size determines the texture and characteristics of the rock, such as porosity and permeability.
18.
Rocks made from sediment laid down by turbidity currents often show
Correct Answer
A. Graded bedding
Explanation
Graded bedding refers to the arrangement of sedimentary layers in which the grain size gradually decreases from bottom to top. This is typically observed in rocks formed from sediment deposited by turbidity currents, which are fast-moving underwater currents that carry sediment and create distinct layers. The sediment settles out in a graded manner, with larger particles settling first and smaller particles settling on top. Therefore, the presence of graded bedding in rocks suggests that they were formed by turbidity currents.
19.
Which of the following is NOT sediment?
Correct Answer
A. Minerals consolidated into a rock.
Explanation
Sediment refers to solid particles that are transported and deposited by water, wind, or ice. The options given describe different types of sediment. "Minerals consolidated into a rock" does not fit the definition of sediment because it refers to a rock that has already formed from the consolidation of minerals, rather than loose particles.
20.
An example of a clastic sedimentary rock is
Correct Answer
D. All answers apply
Explanation
All of the given options, sandstone, mudstone, and arkose, are examples of clastic sedimentary rocks. Clastic sedimentary rocks are formed from the accumulation and lithification of fragments of pre-existing rocks or minerals. Sandstone is composed of sand-sized particles, mudstone is composed of fine-grained particles, and arkose is a type of sandstone that contains a significant amount of feldspar. Therefore, all of the given options are correct examples of clastic sedimentary rocks.
21.
The difference between the sediments gravel, sand, silt, and clay is
Correct Answer
A. Grain size.
Explanation
The correct answer is grain size. The difference between sediments gravel, sand, silt, and clay lies in their grain size. Gravel consists of larger particles, while sand has smaller particles. Silt has even smaller particles than sand, and clay has the smallest particles of all. The variation in grain size affects the properties and behavior of these sediments, such as their permeability, porosity, and ability to retain water.
22.
Fossils are commonly found in igneous and metamorphic rocks.
Correct Answer
B. False
Explanation
Fossils are not commonly found in igneous and metamorphic rocks. Igneous rocks are formed from the solidification of molten material and metamorphic rocks are formed from the transformation of existing rocks under high pressure and temperature. Both of these processes involve intense heat and pressure, which can destroy any fossils present. Fossils are more commonly found in sedimentary rocks, which are formed from the accumulation and compaction of sediment over time.
23.
Clastic or detrital sediment larger than 2 millimeters across is
Correct Answer
A. Gravel.
Explanation
Clastic or detrital sediment larger than 2 millimeters across is classified as gravel. Gravel is composed of rounded or angular fragments of rock that have been transported and deposited by water, ice, or wind. The size of the sediment determines its classification, with gravel being the largest size category. Sand, clay, and silt are smaller sizes of sediment and would not be considered gravel.
24.
Sediment and sedimentary rocks
Correct Answer
A. Don't make up as much volume in the crust as do igneous and metamorpHic (crystalline) rocks but cover the majority of the surface of the continents.
Explanation
Sediment and sedimentary rocks do not make up as much volume in the crust as igneous and metamorphic rocks. However, they cover the majority of the surface of the continents. This means that while they may not be as abundant in terms of volume, they are widespread and play a significant role in shaping the Earth's surface.
25.
Evaporties are formed when chemicals precipitate to form cememt aorund sand-size particles.
Correct Answer
B. False
Explanation
The given statement is incorrect. Evaporites are formed when water evaporates and leaves behind dissolved minerals. They are not formed by the precipitation of chemicals to form cement around sand-size particles. Therefore, the correct answer is False.
26.
You find a sandstone made of well-rounded quartz sand. This likely means that
Correct Answer
D. The sands had a long and hard journey to their place of deposition.
Explanation
The presence of well-rounded quartz sand in the sandstone suggests that the sand particles underwent extensive transportation and erosion before being deposited in their current location. This indicates that the sands had a long and hard journey, possibly being transported by wind or water over a significant distance, before finally settling and forming the sandstone.
27.
Technically speaking, coal is
Correct Answer
D. not made of minerals but it still is a rock.
Explanation
Coal is formed from the remains of plants that lived and died millions of years ago. It undergoes a process called coalification, where heat and pressure cause the organic material to transform into a solid rock-like substance. Although it is not made of minerals like most rocks, it still meets the definition of a rock because it is a naturally occurring solid composed of a single substance.
28.
Texture can be identified as either pegmatitic, phaneritic, aphanitic, porphyritic, glassy, porous, or fragmental.
Correct Answer
B. False
Explanation
The statement is false because texture can be identified as pegmatitic, phaneritic, aphanitic, porphyritic, glassy, porous, or fragmental.
29.
The actions of ____________________ and ____________________ are responsible for most soil erosion.
Correct Answer
wind, water
Explanation
Wind and water are responsible for most soil erosion because they both have the ability to move and transport soil particles. Wind erosion occurs when strong winds blow away loose topsoil, especially in arid or exposed areas. Water erosion occurs when rainwater or runoff flows over the soil surface, picking up and carrying away soil particles. Both wind and water erosion can cause significant damage to the land, leading to loss of fertile soil, decreased agricultural productivity, and increased sedimentation in rivers and lakes.
30.
A vertical sequence of a(n) ____________________ facies shows an offshore facies superposed on nearshore facies.
Correct Answer
transgressive
Explanation
A vertical sequence of a transgressive facies shows an offshore facies superposed on nearshore facies. This means that the transgressive facies represents a period of rising sea levels where offshore conditions encroach upon nearshore areas. This can be seen in the vertical sequence of sedimentary rocks, where the offshore facies is deposited on top of the nearshore facies.
31.
This rock has no visible crystals and has chemical components. Some prehistoric tools were made out of this. The name of this rock is________.
Correct Answer
chert
Explanation
Chert is a rock that does not have visible crystals and is composed of chemical components. It was commonly used to make prehistoric tools.
32.
This rock is biogenic in nature. The name of this rock is________.
Correct Answer
coal
Explanation
Coal is a biogenic rock formed from the remains of plants that lived and died millions of years ago. It is composed mainly of carbon and is formed through the process of coalification. Coal is commonly used as a fuel source for generating electricity and is found in abundance in many parts of the world.
33.
This rock comes from mud, clastic and composed of mica, quartz and feldspar. This rock is called_________________.
Correct Answer
shale
Explanation
The given rock is called shale because it is derived from mud and is clastic in nature. Shale is composed of mica, quartz, and feldspar, which are the minerals present in the rock described. Shale is a fine-grained sedimentary rock that is formed from the compaction of clay, silt, or mud over time.
34.
This rock's grain size is gravel with angular shape, clastic. The minerals present are feldspar and quartz.. The name of this rock is_________________.
Correct Answer
arkose
Explanation
This rock is identified as arkose because it has a grain size of gravel with angular shape, indicating clastic sedimentary rock. The presence of feldspar and quartz minerals further supports this identification. Arkose is a type of sandstone that contains a high percentage of feldspar grains, making it distinct from other sandstones.
35.
This rock is composed of silt and is clastic. The name of this rock is ____________________.
Correct Answer
mudstone
Explanation
The given rock is composed of silt and is clastic, which means it is made up of small particles that have been transported and deposited. Mudstone is a type of sedimentary rock that fits this description, as it is composed of fine-grained silt-sized particles. Therefore, mudstone is the correct name for this rock.
36.
This rock has interlocking crystals and chemical components. It can be found around hot springs. The name of this rock is______________.
Correct Answer
travertine
Explanation
Travertine is a type of rock that is formed from the deposition of minerals from hot springs. It is characterized by its interlocking crystals and chemical components. This rock is commonly found in areas with hot springs and is often used as a building material or for decorative purposes.
37.
This rock is composed of mud and or silt with angular grains. It is usually biogenic because many fossils are found in this type of rock. The name of this rock is_________________.
Correct Answer
limestone
Explanation
The given rock is composed of mud and silt with angular grains. It is usually biogenic because many fossils are found in this type of rock. Based on these characteristics, the name of this rock is limestone.
38.
This rock is composed of sand size grains and has a clastic composition. It is often made up of quartz, calcite and feldspar. The name of this rock is______________.
Correct Answer
sandstone
Explanation
Sandstone is a type of rock that is composed of sand-sized grains and has a clastic composition. It is commonly made up of minerals such as quartz, calcite, and feldspar. Therefore, the given description matches the characteristics of sandstone.
39.
The rock has gravel sized grains and those grain are rounded due to water erosion. It is clastic and lithification is cementing. The name of this rock is___________________.
Correct Answer
conglomerate
Explanation
The given rock is classified as conglomerate because it consists of gravel-sized grains that are rounded, indicating that they have been shaped by water erosion. The process of lithification, specifically cementing, has helped to bind these grains together, forming a cohesive rock.
40.
The grain size is gravel and angular. The components are clastic and the rock is often found in karst areas. The name of this rock is______________________.
Correct Answer
breccia
Explanation
Breccia is a type of rock that is composed of coarse, angular fragments. It is classified as a clastic rock, meaning it is made up of broken fragments of pre-existing rocks. Breccia is commonly found in karst areas, which are characterized by the dissolution of soluble rocks such as limestone. The given description of the rock's grain size, angularity, components, and occurrence in karst areas aligns with the characteristics of breccia.
41.
The rock is composed of pieces of seashells cemented together. The name of this rock is______________.
Correct Answer
coquina
Explanation
The correct answer is coquina. Coquina is a type of sedimentary rock that is made up of fragments of seashells that are cemented together. The rock is typically soft and porous, and it often has a shell-like appearance. Coquina is commonly found along coastlines and is formed in shallow marine environments where seashells accumulate and become compacted over time.
42.
This rock has interlocking crystals of gypsum due to its chemical components. It is prevalent in marine environments. The name of this rock is___________________.
Correct Answer
rock gypsum
Explanation
Rock gypsum is a type of sedimentary rock that is formed from the evaporation of seawater in marine environments. The chemical components of the rock, specifically the presence of gypsum, contribute to the formation of interlocking crystals. Therefore, the given explanation supports the correct answer, which is "rock gypsum."