Pre-Cambrian era

Pre-Cambrian era

all geological time prior to the beginning of the CAMBRIAN PERIOD 590 million years ago. Very few fossils are known from this time and the fossil record effectively begins with the trilobites and brachiopods of the Cambrian. However, impressions of soft-bodied animals such as medusae, sea pens, annelids and some arthropods have been found in Pre-Cambrian rocks dated between 640 and 580 million years old. Bacteria may have existed for up to 3,800 million years and blue-green algae (CYANOBACTERIA) for 3,500 million years.
References in periodicals archive ?
11 (Petra) - Jordanian geologists proposed to experts from the United Nations Educational, Scientific and Cultural Organization (UNESCO) to build the first geological park in Wadi Al-Mujib based on its geological diversity, extending from the pre-Cambrian era which was about 540 million years ago.
Dr Dhiya also brought exhibits with him to make his lecture interesting to students, including rocks dating to the pre-Cambrian era about 560 million years ago.
The reservoirs of both fields are deep and under high pressure; they are among the oldest oil-bearing reservoirs in the world, formed during the pre-Cambrian era about 500m years ago.