PrintBlacktop #2: Crack in blacktop, bike trail. There are no trees nearby, no heavy loads have been driving on this, and there are very few other cracks nearby.Blacktop images one (1) through six (6) will be used to answer questions one and two.
First, examine blacktop pictures 1-6. All six are “blacktop”, not concrete or brick or something else, and you may assume that all of them were similar when new; blacktop is blacktop, and any differences you see have been caused by events since the blacktop was laid down. The pictures are in approximate order of the year in which the blacktop was installed, with the road (1) built most recently, the bike trail (2) older, the road (3 and 4) built before the bike trail, and the nearly-abandoned road (5) and the nearly-abandoned driveway (6) built before 3 and 4, probably with the driveway oldest. The roads 1, 3 and 4 are roads, so they are driven on a lot more than the driveway or the bike trail, but they’re not the main street through town.
We’re going to make a few educated guesses about ways that geology works, based on what we see in these pictures, what we know about roads versus bike trails or driveways, and what we know about the world.
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Blacktop #1: Cracks in blacktop, Puddintown Road. The cracks are especially common where the wheels drive. |
Blacktop #2: Crack in blacktop, bike trail. There are no trees nearby, no heavy loads have been driving on this, and there are very few other cracks nearby. |
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Blacktop #3: Crack in blacktop, edge of Big Hollow road. Cracks in the road are most commonly at the edge, or under the wheel tracks. |
Blacktop #4: Crack in blacktop, Big Hollow Road. The road is slanted here, and the broken-up part may be sliding downhill a little. Notice that the cracks are damp and plants are growing in some cracks. The township has patched this, at least twice, but is still losing. |
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Blacktop #5: A small section of road off Houserville Road, no longer regularly used, but rather old for blacktop. Notice that to the upper right and left the blacktop is almost completely gone. Some cracks are damp here, too, with plants growing in some. |
Blacktop #6: Abandoned blacktop driveway in Houserville. This is a little hard to even recognize as a driveway. |
Study these pictures, print them if you like, and then go back to answer Exercise #2, Questions #1 and #2.