Colorado GEO 101 – the information about the hydrologic

Lab 3 Instructions and questionsRead the information about the hydrologic cycle and groundwater in Chapter 3 of thetext book. This lab will focus on porosity and permeability.Prelab questions1.2.3.4. Describe the zone of saturation.Explain how the water table can move up or down.How does the sediment size in an aquifer affect the rate of recharge?Define porosity and permeability. Exercise 1 – PorosityMaterials:1.2.3.4.5.6. 250 ml beakerSample B in rock collectionSample F in rock collectionScalePaper towel* (not in kit)Water* (not in kit) Complete the following experiment:1. Using the materials in your lab kit, complete the following:2. Using rock sample B (sandstone) and rock sample F (dolomite), use the scale inthe kit to determine the weight of each sample in grams. Record these weights inthe table below.3. Place both samples in 100 ml of water checking for bubbles as you do so.4. Let samples sit in water for 30 minutes.5. Remove the samples from the water, gently dry with paper towel, and weightthem again. Record the wet weight in the table.6. Calculate the difference between wet and dry for both.7. Answer the questions below.Sample Dry weight(grams) Did you seebubbles inwater? Wet weight(grams) Difference inweight (grams) Sample BSandstoneSample FDolomite1. Which rock produced the most bubbles?2. Which has more porosity, tightly packed particles or loosely packed particles? 3. Which of these samples is most porous?4. Why do you think rocks with rounded grains absorb more water than rocks withinterlocking grains?5. Would dolomite make a good aquifer? Exercise 2 – Measuring PermeabilityMaterials* (all materials found in kit):1. 100 ml beaker2. 4 coffee filters3. Large funnel4. 4 glass test tubes5. Test tube rack6. Marker7. Ruler8. Gravel9. Sand10. Potting soilComplete the following experiment:1.2.3.4.5.6. 7.8.9. Place a test tube in the test tube rack, place funnel inside.Fold a coffee filter into quarters, open inside funnel.Fill funnel with gravel to about ½ an inch from the top.Mark a line on the test tube at the bottom of the sediment in the funnel….e the ruler to measure the distance in cm from the line to the top of thesediment in the funnel. This will be the ‘distance traveled’ for the table below.Pour water from the beaker into the sediment. Using a clock, determine the timein seconds it takes for the water to reach the line on the test tube. This will be the‘time elapsed’ for the table below.Repeat all steps with the sand, the potting soil, and a mixture of ½ sand, ½gravel. Record your data in the table below.Calculate the permeability by the distance traveled divided by time elapsed. Thiswill give you a number in cm/s.Answer the questions below. Sediment typeGravelSandPotting soil Distance traveled(cm) Time elapsed (s) Permeability (cm/s) Mixture sand andgravel1.2.3.4. Which material was the most permeable? Which was the least permeable?Which sediment type would be good for aquifers?Are paved parking areas permeable? Porous? How can you tell by sight?Henry Philibert Gaspard Darcy, born in 1803, was assigned to find a water supplyfor a town in France. Drilling a well didn’t produce enough water, so he used aseries of gravity-driven pipes from surface water for water supply. His ongoingresearch on the rate of flow of groundwater produced this formula:V = K(G)V = groundwater velocity; K = hydraulic conductivity describes how easily groundwater flows through a certainrock or soil;G = hydraulic gradient, the slope of the water tablea. What would Darcy’s Law predict would happen to the rate of flow ofgroundwater as the hydraulic gradient, (i.e. the slope of the water table)increased?