Logging tasks.
- Look at the conglomerate. what is the size and makeup of the stones.
- Are the stones similar? different types of stones?
- Pick some stones that are different, are they worn down differntly? What might this mean?
- Pick up a rock and tap it against the conglomorate, then against a sandstone/limestone rock that is nearby, Is there a difference in sound? Why might that be?
- Add a photo of you from the location or of an identifiable item (paper with trackable name). Posting a photo pulled from the internet, or photoshopped will result in instant deletion.
Behold rocks. You are looking for a large stone, about fifteen feet long, four feet high and sixish feed wide that has broken in half. You cant really miss it.
Here you have a few different stones that have tumbled on top of each other from different eras.
Far up on the cliff to your south is the cap of a ridge. That is made of a conglomorate stone from the Eocene Epoch of the Tertiary Period. Blah blah blah. what does that mean to you? now? here?
Well as the first tiny horses were walking about, and the first bats flew in the sky 40-50 million years ago this was at the edge of an ocean. How can you tell? Well much of the stone that is around you is limestone. Limestone is made up of calcium that filtered down to make the ground around you. If you look to the NW you can see the remains of two old lime kilns that used that limestone to make products for the people that lived here.
At some point a river would have entered that ocean. It would need to be at the mouth of a rapid moving river. How can you tell? Well slow moving rivers drop sand, silt and clay. Those tend to form sandstone, slates, mudstone, etc. However a river that is moving rapidly or a wash would be depositing materials like stones, and other larger materials.
Another option is the flow. If the stones are all similar in size/weight then the river held a steady flow. Dropping them out at the same rate for some time. If the river was uneven, and flowed differently because of the seasons the rock sizes would vary. If there were heavy floods followed by dry or nearly dry periods you may see a fist sized rock, or larger, and a number of smaller ones all together.
You can look at the large stone that fell from the heights above. Landed here and broke in half. It is part of that old riverbed. Stones that are mostly the same size are dumped together. they eventually cemented for form this harder stone. It has the look of a old piece of weathered cement.
One of the things you can tell is how far the stones traveled to get into the conglomerate. Well not exactly. A stone that is rolled, round and like little balls, would have traveled far down a river, tumbling and wearing the edges smooth, while others only lightly wear the edges. Some might have broken off and been carried only a little ways. The stones would be sharp and not worn at all.
In many river mouths as the river slowed the rocks would have dropped out evenly. Larger stones dropping upstream, then as the river slows the smaller stones stop rolling, then eventually the sand, silt and clay would all drop out to the bottom eventually covering the ground.
