1 For subsidence caused by sudden collapse of the ground to form sinkholes, several measures can be taken. 2  First, geologists can make maps of areas known to be underlain by rocks like limestone, gypsum, or salt, that are susceptible to dissolution by fluids.
The Navajos used bows and arrows, spears, clubs, tomahawks, knives and sticks among their tools and weapons. Beyond these, they also used bolas and... The Navajos used bows and arrows, spears, clubs, tomahawks, knives and sticks among their tools and weapons. Beyond these, they also used bolas and blowguns. The Navajos employed the use of several tools and weapons:Bows and arrows were used by Native Americans to defend themselves, and sometimes for fishing. They also used them for hunting animals like bison.When fighting against European explorers, Native Americans used spears.
Native Americans lived in a wide variety of homes. Different tribes and peoples built different types of homes. What kinds of homes they lived in depended on the materials that they had available where they lived.he hogan was the home built by the Navajo people of the Southwest. They used wooden poles for the frame and then covered it in adobe, clay mixed with grass. It was generally built in a dome shape with the door facing the east toward the sunrise. There was also a hole in the roof for the smoke of the fire to escape.