Soil Texture Quantitative Test

     In this experiment, we placed 65mL of our soil into a 100mL graduated cylinder. Then added water until the level got to the 100mL mark. Next, we put our hand over the open end of the graduated cylinder and shook the graduated cylinder until the soil and water was mixed thoroughly. Once the soil and water were completely mixed, the graduated cylinder was placed at our lab table for 24 hours to allow the soil to settle out. Once the soil settled out, we used a yard stick to measure each layer of the soil and the whole soil together. We measured that 12.4 cm was clay, 0.4cm was sand, and 0.3 was silt.

Here we can see the soil being measured to 65mL.

Water was added to the soil until the level was at 100mL, as seen in the picture.

The soil and water was shook until completely mixed.

After being shook the soil and water measured 72mL. You can see that parts of our soil is sticking to the edges of the graduated cylinder which hints towards our soil being clay.

After 24 hours, you can see the clay, sand, and silt settle out. The sand is on the bottom, then the silt, and then the clay on top. You can see a layer of water on top of the clay and a layer of humus on top of the water.

The yard stick was placed next to the graduated cylinder. There was 12.4cm of clay, 0.4cm of sand, and 0.3cm of silt.

Using these measurements, we calculated the percent of sand, clay, and silt in our soil.  We found that there is 81.05% clay, 2.61% sand, and 1.96% silt. 

After looking at our percents, we determined our soil is clay. Our shaded region is a little bigger  because our percents of clay, sand, and silt did not come out to 100% because there was also water and humus in the soil.

     Our qualitative and quantitative results match because they both said that our soil was clay. Even during our quantitative test you could see the moist soil sticking to the graduated cylinder, which was like in he qualitative test of how the soil had clay properties.
   
     Our percolation test and quantitative test results did match because in the percolation test the soil had an elapsed time of 26.5 seconds and a water volume of 71.8mL. these numbers were very similar to the clay's numbers of 29.0 seconds and 63.5mL. This hints that our soil had a lot of clay in it. Our quantitative results also showed that our soil had a lot of clay.

     My group got our soil by the school and our soil was mainly clay. Hannah's group, who got their soil from cuba marsh, had mainly silt soil. Troy's group, who got their soil from his backyard, had an equal amount of all three components. Although they had an equal amount of sand, silt, and clay, on the texture triangle this soil still falls under clay soil. According to the United States Geological Survey, clay deposits can only form under certain geological conditions. The only environments that clay deposits can form under are soil horizons, continental and marine sediments, geothermal fields, volcanic deposits and weathering rock formations. The area around the school that we got our soil could be soil horizon or from sediments. Troy's backyard would also need to have one of these conditions to form clay soil. Silt soil is formed usually in wetlands when rock is eroded by water and ice. As flowing water transports tiny rock fragments, they hit the sides and bottoms of stream beds, which cause them to break off more rock. The particles grind against each other and become smaller and smaller until they are silt-size. The cuba marsh has a wetland in it, which can explain why Hannah's group got silty soil.