Description of manganese nodules collected in a metamorphic limestone Cambria...

In the Philipsburg district, in western Montana a low arch of a Paleozoic limestones has been cut and deformed on the east and a south sides by a small batholith of Tertiary...在蒙大拿州西部的菲利普斯堡地区，一处低缓拱曲的古生界石灰岩构造，其东侧与南侧被一处第三纪小型岩基切割并发生变形……