Earth formed about 4.57 b.y. ago. Most meteorites and the oldest rocks from the lunar highlands are of this age. There are no surviving rocks from Earth of this age, though there are zircon crystals in Archean rocks that range in age up to 4.3 to 4.4 Ga. These resistant minerals survived the destruction of the rocks that they originally crystallized in.
Early Earth was very hot from gravitational compression of the Earth's interior as it grew in size, from meteor bombardment, and from 5 times as much radioactive decay as there is today. There are no remnants of early Earth's surface because of constant resurfacing through volcanism, subduction, and meteor bombardment. Heavy meteor bombardment ended by around 3.8 b.y. ago (most of the craters on the moon are that age or older).
The early crust was probably ultramafic (komatiite) because early Earth was so hot that the ultramafic mantle could melt completely or to a high degree, thereby yielding an ultramafic melt which rose to the surface and solified forming an ultramafic volcanic crust. Today the Earth is much cooler and the ultramafic mantle can only melt to a small degree (1-10%), for example via decompression melting beneath midocean ridges or by flux melting in subduction zones. This partial melting of ultramafic mantle rocks yields mafic magmas which may erupt as basalt or differentiate further as they rise to form intermediate (andesite) and felsic (rhyolite) lavas.
Archean Geology: 4 - 2.5 b.y. ago From the Oldest Remaining Crust to the Formation of Minicontinents
"Normal" plate tectonics probably didn't exist because of the high heat flow and volcanism rapidly resurfacing the Earth in small-scale random patterns, compared with today's generally broad plates and widely separated midocean ridges and subduction zones.
Very little crust older than 3 b.y. still exists. Some of the oldest crust contains the chemical signature of formation in a subduction zone/volcanic arc setting.
Greenstone belts (metamorphosed komatiite, basalt, and sediments) and granite/tonalite (most metamorphosed to gneiss) terranes characterize Archean geology; the felsic granite/tonalite gneiss formed by partial melting of the ultramafic mantle, probably over subduction zones like the Andes Mountains or Aleutian Islands today; the greenstones formed either from ocean crust or as back-arc basins; continental crust grew by island arcs (granite/tonalite gneiss) colliding and suturing together, often trapping slices of ocean crust or back-arc basins (greenstones).
The end of the Archean Eon, between about 2.6 and 2.5 Ga was a period of major crustal formation, crustal thickening, and aggregation of mini continents from smaller pieces of Archean crust (microcontinents/island arcs). The Algoman Orogeny in the Great Lakes region and the Kenoran Orogeny in Canada resulted from these collision/crust-forming events. Much of the crust that now makes up the Canadian shield was formed at that time, though it had not yet amalgamated together. It remained as widely separated minicontinental terranes.
Proterozoic Geology: 2.5 b.y. - 543 m.y. ago The Formation of Continents
The Hudsonian orogeny in the mid-Proterozoic around 1.7 b.y. ago sutured together various Archean mini continents into the core of the stable continent Laurentia, the core of ancestral North America.
Other terranes accreted to Laurentia following this (e.g., the Yavapai & Mazatzal terranes across southern Laurentia). Laurentia grew outward from the core.
The Grenville Orogeny ~ 1 b.y. ago produced a large metamorphic belt in eastern and southern Laurentia. The Grenville mountains have long since eroded away leaving only the metamorphic core of the mountains
Passive margin subsidence yielded thick Upper Proterozoic/Lower Paleozoic sedimentary sequences in present day western Canada and the eastern US.
So, how do we account for these late Proterozoic geologic events?
problem: So, what did Laurentia collide with 1 b.y.a. and rift away from ~700 m.y.a.??? How would we find the other continent? solution: Look for another continent with 1 b.y. metamorphic belt and 700 m.y. passive margin sequence.
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The Grenville orogeny in eastern Laurentia about 1 b.y. ago apparently resulted from assembly of a supercontinent that has been named Rodinia which contained ancestral cores of today's continents.
Rodinia Breakup
First, western Laurentia rifted from the region of Rodinia that later became Australia, and southern and southeastern Laurentia rifted from what became Antarctica.
Later, eastern Laurentia rifted from ancestral South America.
Rodinia gradually separated into several major continents including Laurentia (second incarnation), Gondwana (Antarctica, Africa, South America, India, and Australia), and Baltica (northwestern Europe)