The two subdivisions of the Precambrian Era are the Hadean and the Archean Eons.
The two basic divisions following the Precambrian on the geologic time scale are the Paleozoic Era and the Mesozoic Era. These eras are further divided into periods, such as the Cambrian, Devonian, and Permian in the Paleozoic Era, and the Triassic, Jurassic, and Cretaceous in the Mesozoic Era.
The two gases that probably dominated Earth's atmosphere during the Precambrian era were carbon dioxide (CO2) and nitrogen (N2). These gases were likely present in much higher concentrations than oxygen.
there are different periods in each era. In the Cenozoic era, there are 2 periods, Quaternary and Tertiary. Mesozoic era has 3 periods, Cretaceous, Jurassic, and Triassic. Paleozoic has 7 periods, Permian, Carboniferous, Devonian, Silurian, Ordovician, and Cambrian. Precambrian is just the present, no time periods in it.
EonEraPeriodEpoch! :)
Precambrian rocks are typically very old, dating back over 600 million years. They often contain minerals like quartz, feldspar, and mica due to their formation process in the early Earth's crust.
Archeozoic and ProterozoicThe two periods of the Cenozoic Era are the Tertiary and the Quatemary.
The two basic divisions following the Precambrian on the geologic time scale are the Paleozoic Era and the Mesozoic Era. These eras are further divided into periods, such as the Cambrian, Devonian, and Permian in the Paleozoic Era, and the Triassic, Jurassic, and Cretaceous in the Mesozoic Era.
The Precambrian Era. The name means: "before the Cambrian period." This old, but still common term was originally used to refer to the whole period of earth's history before the formation of the oldest rocks with recognizable fossils in them. In the last few decades, however, geologists have found that there are some hard-to-discern fossils in some Precambrian rocks, so this period is now also known as the Cryptozoic or "obscure life" Eon (from the words "crypt" = "hidden," and "zoon" = "life"). The Precambrian covers almost 90% of the entire history of the Earth. It has been divided into three eras: the Hadean, the Archean and the Proterozoic. Source: Unknown The Precambrian Era comprises all of geologic time prior to 600 million years ago. The Precambrian was originally defined as the era that predated the emergence of life in the Cambrian Period. It is now known, however, that life on Earth began by the early Archean and that fossilized organisms became more and more abundant throughout Precambrian time. The two major subdivisions of the last part of the Precambrian are the Archean (oldest) and the Proterozoic. Rocks younger than 600 Ma are considered part of the Phanerozoic.
The two gases that probably dominated Earth's atmosphere during the Precambrian era were carbon dioxide (CO2) and nitrogen (N2). These gases were likely present in much higher concentrations than oxygen.
The two subdivisions of the Dorsal Cavity are the Cranial Cavity and the Vertebral Cavity.
Psilotum is divided into two main subdivisions: Psilotum and Tmesipteris. These subdivisions are based on differences in sporangial structure and plant morphology.
No. The Precambrian Era extended from 4.5 billion years ago to 542 million years ago. The Mesozoic Era lasted from 251 million years ago to 65 million years ago. The Paleozoic Era came in between the two.
yea
When the continents were one big land mass it was called Pangaea, the great land mass of Pangaea split in two creating, Laurasia and Gondwanaland.
Spinal vertebra are called just that. There are subdivisions: cervical (neck), thoracic (chest), and lumbar (lower back). There are two sets that have fused in the adult: the sacrum and the coccyx (tail bones).
peripheral nervous system
The Era of Good Feelings