Geology Quiz Answers Chapter 15

Chapter 15: ● Weathering is the change in the physical and chemical character of rock exposed at Earth's surface. Identify the ways in which mechanical and chemical weathering can be differentiated from one another. ○ Mechanical weathering involves breaking rock apart, whereas chemical weathering involves the breakdown of minerals in the rock. ○ Rocks subjected to mechanical weathering do not change in composition, whereas rocks undergoing chemical weathering do change in composition. ● Which of the following describes the process of unloading? ○ Rocks fracture as overlying rock is removed. ● Minerals that form deep within Earth ______ in response to the new conditions of temperature, pressure, and moisture at the surface. ○ will change ● Most of the salt in the oceans is derived from ______. ○ weathering of rocks on land ● How a mineral weathers depends on time of exposure, the surrounding climate, and the mineral's ______. ○ chemical composition ○ atomic structure ● The decomposition of rock resulting from exposure to water and atmospheric gasses is referred to as ______. ○ chemical weathering ● Limestones are often formed in tropical settings. However, ancient limestone now found in this same type of climate can be very susceptible to erosion. Why is limestone unstable in the same climate it was formed? ○ Limestone formed underwater is now exposed to weak acids carried by abundant surface water in this warm climate. ● The spalling off of slabs of rock along sheet joints (similar to peeling layers from an onion) is called ______. ○ Exfoliation ● Which of the following minerals commonly found in granite is the most resistant to physical and chemical weathering? ○ Quartz ● Minerals formed at depth within Earth may be unstable at the surface due to very different ______ conditions. ○ moisture ○ temperature ○ Pressure ● When ocean water evaporates, the dissolved salts ______. ○ remain in the sea ● Rank these locations by their weathering rates. Place the city with the highest weathering rate at the top. ○ São Paulo, Brazil ○ Dublin, Ireland ○ Vostok Station, Antarctica ● True or false: How a mineral weathers depends only on the climate in which it is located. ○ False ● Chemical weathering is generally more intense on the corners and edges of a block of rock, resulting in the rock becoming rounded. This weathering feature is known as _______ weathering. ○ Spherical ● One of the primary ways in which climate affects weathering is through the presence of ______ which enhances both physical and chemical weathering. ○ Water ● Mafic minerals in granite weather both through hydrolysis to form clay minerals, and through ______ to form hematite. ○ Oxidation ● What type of weathering has caused this rock to look like it does? ● ● ● ● ○ ○ Differential weathering The process of ______ can weather calcium carbonate in limestone to form caves along fractures or below the water table. ○ Dissolution Chemical weathering occurs ______ in warm, humid areas than it does in cold, dry settings. ○ Faster A landscape that is characterized by sinkholes, disappearing streams, and gray weathered rocks is called ______ topography. ○ Karst The type of chemical weathering that has caused the red coloring on this hillside is ______. ○ ○ Oxidation ● This landscape of karst topography ______. ● ● ● ● ● ● ● ● ● ● ● ○ ○ is pitted from dissolution ○ lacks developed surface water drainage systems The most common type of rock to be dissolved and form caves is ________. ○ Limestone Which of the following countries or regions have widespread karst formations? ○ Central Asia ○ Europe ○ Southeast Asia What is a soil horizon? ○ A horizontal zone of soil distinct from adjacent layers Describe the formation of soil by ranking these descriptions from first to last. ○ Material is derived from the erosion of underlying rocks ○ Organic materials build up on the surface ○ Vertical movement of dissolved materials segregates the profile into different horizons Soil that has a deep red color from the accumulation of iron and aluminum oxides is common in _______ climates. ○ Tropical Sinkholes may be large collapsed holes or small and subtle pits in a landscape of _____ topography. ○ Karst The distribution of karst across the world is roughly equal to the distribution of ______. ○ soluble rocks Distinct layers that form in soil and can be distinguished from one another by appearance and chemical composition are referred to as ______. ○ soil horizons Climate affects soil formation primarily by controlling weathering processes and ______. ○ Vegetation The layer of weathered, unconsolidated material that contains organic matter and is capable of supporting plant growth, called ______ by most people, is referred to by geologists as regolith. ○ Soil The soil profile shown here is from a ______ climate. ● ● ● ● ● ● ● ● ● ● ● ● ○ ○ Temperate Thick red soils that are highly leached by heavy rainfall in a warm climate are called ○ Laterites We rely on soil to ______. ○ grow our food ○ provide natural resources ○ provide shelter How soil forms within a setting is a direct reflection of the area's _____ ○ Climate The relationship between soil and plants is ______. ○ Mutually beneficial What is the name given to thick red soils that are highly leached and generally infertile? ○ Laterite Livestock or indigenous animals remove vegetation leaving soil vulnerable to erosion when ______ occurs. ○ Overgrazing How does vegetative cover benefit soil? ○ Protection from runoff erosion ○ Helps to capture water ○ Protection from wind and rain What is the relationship between soil and plants? ○ Both rely on each other for healthy development. How does deforestation lead to soil erosion? ○ Severed roots decay and no longer hold soil in place. Loose water-filled soils can become ______ when shaken during an earthquake. ○ Liquefied Overgrazing and ______ are two poor land management practices that threaten soil. ○ Deforestation Terracing is a practice that ______. ○ allows farming in areas that would otherwise be too steep ○ promotes soil formation ○ protects soil from erosion ● Deforestation often occurs when people clear land for agriculture, but the process often results in _______ erosion, thereby making the land useless for growing crops. ○ Soil ● Soils that contain a high volume of certain ______ minerals will swell when wet and shrink when dry. Repeated cycles of this expansion and contraction can be problematic for roads and buildings. ○ ○ Clay