542 MA PHANEROZOIC EON (542MA-p)

PALEOZOIC542 ERA (290 M) (542-251 MA)

CAMBRIAN542 PERIOD (53.7 M) (542-488.3 MA)

Vendian Supercontinent (Pannotia) breaks up in Early Cambrian

Avalonia drifts northward from Gondwana

Iapetus Ocean (600-400 MA)

Many aquatic plants

Some plants invade land

First shell-forming invertebrate animals - attributed to rising alkilinity of ocean

Trilobites

Paradoxides - large Middle Cambrian trilobite of the Atlantic/Avalonian faunal culture - good guide fossil

Bracholopods and many other invertebrates

Shell fossils begin to appear commonly

EARLY CAMBRIAN EPOCH (29 M) (542-513 MA)

TERRENEUVIAN EPOCH (21 M) (542-521 MA)

FORTUNIAN STAGE (14 M) (542-528 MA)

528 MA STAGE 2 (7 M) (528-521 MA)

521 MA SERIES 2 (11 M) (521-510 MA)

STAGE 3 (6 M) (521-515 MA)

513 MA MIDDLE CAMBRIAN EPOCH (12 M) (513-501 MA)

515 MA STAGE 4 (5 M) (515-510 MA)

510 MA SERIES 3 (11 M) (510-499 MA)

STAGE 5 (3.5 M) (510-506.5 MA)

506 MA DRUMIAN STAGE (3.5 MA) (506.5-503 MA)

503 MA GUZHANGIAN STAGE (4 M) (503-499 MA)

501 MA LATE CAMBRIAN EPOCH (12 M) (501-488.3MA)

500 MA Gondwana Supercontinent forms (-200MA)

499 MA FURONGIAN EPOCH (10.7 M) (499-488.3 MA)

PAIBIAN STAGE (3 M) (499-496 MA)

496 MA STAGE 9 (4 M) (496-492 MA)

492 MA STAGE 10 (3.7 M) (492-488.3)