Cryptic (geology)
The Cryptic era is an informal term for the earliest geologic evolution of the Earth and Moon. It is the oldest (informal) era of the Hadean eon, and it is commonly accepted to have begun close to 4533 million (about 4.533 billion) years ago when the Earth and Moon formed. No samples exist to date the transition between the Cryptic era and the following Basin Groups era for the Moon (see also Pre-Nectarian), though sometimes it is stated that this era ended 4150 million years ago for one or both of these bodies. Neither this time period, nor any other Hadean subdivision, has been officially recognized by the International Commission on Stratigraphy.
Hurrians
The Assyrian Empire collapsed from 620 to 605 BCE, after a series of brutal internal civil wars weakened it to such an extent that a coalition of its former vassals; the Medes, Persians, Babylonians, Chaldeans, Scythians and Cimmerians were able to attack and gradually destroy it. Urartu was ravaged by marauding Indo-European speaking Scythian and Cimmerian raiders during this time, with its vassal king (together with the king of neighbouring Lydia) vainly pleading with the beleaguered Assyrian king for help. After the fall of Assyria, Urartu came under the control of the Median Empire and then its successor Persian Empire during the 6th century BCE. During the 2nd millennium BC a new wave of Indo-European speakers migrated over the Caucasus into Urartian lands, these being the Armenians. It is argued on linguistic evidence that proto-Armenian came in contact with Urartian at an early date (2nd millennium BC), before the formation of the Urartian kingdom. In the 6th century BCE the region became part of the Armenian Orontid Dynasty. The Hurri-Urartians seem to have disappeared from history after this, almost certainly being absorbed into the Indo-European Armenian population.