GEO 109 Exam 4 Questions Written With Correct Detailed Answers.

Groundwater - correct answers Water that exists beneath Earth's surface in soil pore spaces and rock fractures. Where most liquid fresh water exists Hydrogeology - correct answers The study of groundwater and its movement through soil and rock formations Hydrogeologist - correct answers A scientist who specializes in studying groundwater systems Porosity - correct answers The percentage of void space (holes or pores) in a rock or sediment that can hold water Permeability - correct answers The ability of a material to transmit fluids through its pores; how well connected the pores are Aquifer - correct answers A subsurface layer of permeable rock or sediment that can store and transmit significant quantities of water Aquitard - correct answers A layer of low-permeability rock or sediment that restricts water flow Recharge - correct answers The process by which water enters and replenishes an aquifer Discharge - correct answers The process by which water exits an aquifer (through springs, wells, or into streams) Confined - correct answers An aquifer that is sandwiched between two impermeable layers (aquitards) Unconfined - correct answers An aquifer with no upper confining layer; the water table forms its upper boundary Spring - correct answers A natural discharge point where groundwater flows to the surface Hot Spring - correct answers A spring where geothermally heated groundwater emerges at the surface Geyser - correct answers a hot spring that periodically erupts with steam and water Mudpot - correct answers A hot spring with limited water that creates bubbling mud Water Table - correct answers The upper surface of the saturated zone in an unconfined aquifer Infiltration - correct answers The process of water seeping into the ground from the surface Artesian Well - correct answers A well drilled into a confined aquifer where pressure causes water to rise without pumping Impermeability - correct answers a material does not allow water to flow through it; the pores are not connected or are too small for water transmission Primary porosity - correct answers Original pore spaces formed when the rock/sediment was deposited (e.g., spaces between sand grains) Secondary porosity - correct answers Pore spaces created after formation through fracturing, dissolution, or weathering (e.g., fractures in granite) Good aquifer - correct answers High porosity AND high permeability (e.g., sand, gravel, fractured rock) Poor aquifer/aquitard - correct answers Low permeability, even if porosity is high (e.g., clay, unfractured shale) Saturated zone - correct answers below the water table...all pore spaces are completely filled with water vadose zone - correct answers above the water table...pore spaces contain both air and water Sheetwash - correct answers Broad, thin flow of water over the ground surface, not confined to channels Dendritic - correct answers A tree-like drainage pattern formed in uniform bedrock; most common pattern Radial - correct answers A drainage pattern where streams flow outward from a central high point (like a volcano) Rectangular - correct answers A drainage pattern with right-angle bends controlled by fractures or joints in bedrock parallel - correct answers A drainage pattern where streams flow parallel to each other, common on steep slopes Trellis - correct answers A drainage pattern resembling a garden trellis, common in folded mountain regions Competence - correct answers The largest particle size a stream can transport at a given velocity Drainage divides - correct answers The boundary/ridge separating one drainage basin from another drainage basin - correct answers the area from which a single stream or river and its tributaries drains all of the water Hyporheic zone - correct answers The saturated zone beneath and alongside a stream where stream water and groundwater mix Perennial - correct answers A stream that flows year-round because it intersects the water table; channel lies below the water table Ephemeral - correct answers a stream that flows only during and immediately after precipitation events; above the water table Thalweg - correct answers The line connecting the deepest points along a stream channel; the path of fastest flow Slump - correct answers a type of mass movement where material rotates backward along a curved failure surface dam - correct answers a barrier constructed across a stream to control water flow and create a reservoir creep - correct answers slowest type of mass movement, occurring at rates of millimeters to centimeters per year slope angle - correct answers most important factor in determining if an area will be subject to mass movement gravity - correct answers what mass movements are driven by What a slump looks like - correct answers backwards-tilted block with a curved scar at the top and often shows trees tilted backward. Mass wasting events - correct answers classified by the type of movement (fall, slide, flow) and the type of material involved (rock, debris, earth) Decreasing mass movement/landslide hazards - correct answers reduce slope angles, improve drainage to reduce water content, add vegetation for root support, install retaining walls or other engineering structures, and avoid construction on unstable slopes How moisture affects stability of sediment grains - correct answers Small amounts of moisture increase cohesion (surface tension holds grains together), Excessive moisture reduces friction between grains and adds weight, decreasing stability, and saturation can lead to liquefaction saltation - correct answers the bouncing movement of sediment particles (typically sand-sized) along a streambed, where particles are lifted briefly then fall back down due to turbulent flow headwater - correct answers beginning of a stream cut bank - correct answers the steep bank feature that forms on the outside of a river bank due to erosion point bar - correct answers deposit of sediment build up by a river on the inside bend of a meander floodplain - correct answers he flat area adjacent to the stream channel that is inundated during high flow events. meandering stream - correct answers stream with a sinuous (snake-like) channel pattern with curves and bends, typically found in lower-gradient areas with fine sediment. stream gradient - correct answers the slope of a stream channel, typically expressed as the change in elevation per unit distance (e.g., meters per kilometer or feet per mile)