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.
They would further shape the flake beating it with a bone or stone until it took on a more finished shape. They would then use a pointed bone or stone to chip flakes of the edge of the arrowhead to created a serrated edge. So there were different tools, a bone or stone hammer, a bone or stone 'flaker' to make the edge. Fire was used as a tool and some used leather pads as gloves. Some indians even used very basic hand or bow powered drills to help fashion items. I'm sure there were many other tools and methods. Hope that helps. -tony