Video Glossary: Naturally Layered Stone скачать в хорошем качестве

Video Glossary: Naturally Layered Stone

Many things in nature occur in layers. So, this is an example of some of the rocks that would have occurred in western Wisconsin. They're called sedimentary rocks, so they're layer after layer of different kinds of sands or silts or clays that were laid down by wind or by water millions of years ago. And they will tend to break along these layers. You can see how this is cracked along here, we've got another crack that's coming along here, and here's a layer over here where the material is breaking. So up here we have, um, softer material, and then in the places where it's harder we have much more concentrated, much harder material. It doesn't erode as well, so it ends up being left as loose nodules. We can see many examples of natural layers in the rock, such as this sandstone or nodules. This is a natural nodule formed around something, so it's layer after layer forming around a circle. The same thing with this one. This is a natural piece of stone that was formed in layer after layer in a nodule. Sometimes we can see that there are breaks coming along fracture planes. So, these are frost lines or other kinds of natural breaks in the rock, and at some point the stone is just going to break along those natural fracture planes. And you can see here that the stone itself has many layers, just like our chunk of bedrock over here. Other stone such as this, you can see all of the different layers in the stone, and it's breaking along one of those natural layers, and another place where it's breaking along that natural layer. Sometimes somebody was making an artifact, and they didn't think they had a problem, but this is a biface that was broken when they were working because it turns out that there was just a thin line of material, there was just a thin inclusion of material, that was a little bit weaker than the rest, and the stone snapped right along that line. So many breaks are natural. They're following natural bedding planes in stone. Links for further information: Related MVAC webpages: -Flintknapping: https://www.uwlax.edu/mvac/educators/... -Lab Analysis - Lithic Analysis: https://www.uwlax.edu/mvac/process-of... -Lithics: https://www.uwlax.edu/mvac/educators/... -Making Stone Tools: https://www.uwlax.edu/mvac/pre-europe... -Sandstone: https://www.uwlax.edu/mvac/educators/... -Technologies - Lithics: https://www.uwlax.edu/mvac/past-cultu... Related MVAC videos: -Characteristics of an Artifact: Chipped Stone – MVAC’s Dr. Connie Arzigian describes how archaeologists define and recognize chipped stone artifacts:    • Characteristics of an Artifact: Chipped Stone   -Cultural vs. Natural: Chipped Stone – Dr. Arzigian shows how to distinguish culturally worked chipped stone from naturally worn or layered stone:    • Cultural vs Natural: Chipped Stone   -Groundstone Tools vs Natural Stone – Dr. Arzigian talks about different types of groundstone tools and ways to tell if a stone has been naturally worn or intentionally ground:    • Groundstone Tools vs Natural Stones   -How to Recognize Pottery – Sometimes banded nodules can look like pottery sherds. Dr. Arzigian explains how to differentiate between natural stone and pottery in this video:    • How to Recognize Pottery   Artifact Identification Mississippi Valley Archaeology Center at the University of Wisconsin–La Crosse works mainly in Wisconsin, Minnesota, and Iowa and can provide information related to that region. If you would like information on artifacts, email a description of the item and where it was found, and attach a picture of the artifact with a scale to show its size. For more information visit MVAC’s website at: https://www.uwlax.edu/mvac/contact/. For information on other regions, we suggest contacting the appropriate state archaeologist from the following list: https://sites.google.com/view/state-a....