Cimmerian Orogeny Cimmerian Orogeny The Cimmerian Orogeny was an orogeny that created mountain ranges that now lie in Central Asia. The orogeny is believed to have begun 200–150 million years ago (much of the Jurassic Period), when the Cimmerian plate collided with the southern coast of Kazakhstania and North and South China, closing the ancient Paleo-Tethys Ocean between them. The plate consisted of what are now known as Turkey, Iran, Tibet and western Southeast Asia. Much of the plate's northern boundary formed mountain ranges that were as high as the present-day Himalayas. The orogeny continued well into the Cretaceous and Early Cenozoic.
Nevadan orogeny deformation from the Nevadan Orogeny in the Eastern Belt is somewhat limited. It was determined that the deformation was minimal in the Eastern Belt by looking at dikes that had intruded the rocks which appeared to be mostly undeformed. These mostly undeformed dikes were dated using the K-Ar method and were determined to be between 169 and 209 Ma in age, which implies they were placed well before any deformation related to the Nevadan Orogeny would have occurred. As the age of these dikes are older than the deformation of the Nevadan Orogeny, it is evident that most of the