how many years was the Earths land mass in 1 piece; and how long ago was that?

Answer 1

you are speaking of Pangea..it started breaking up about 250 million years ago

Answer 2

It is very unlikely that Rodinia was the first supercontinent. However, it was certainly the first global supercontinent -- incorporating essentially all of the Earth's continents -- about which we have solid information. Rodinia formed perhaps as early as 1200 Mya. Most of its mass was probably located in the low latitudes of the Northern Hemisphere. However, the actual arrangement of cratons is still being debated. Laurentia (North America) seems to have been the hub of Rodinia. At the time, Laurentia was rotated about 90° clockwise with respect to its present orientation, so that Greenland was on the East side. Baltica (northern and eastern Europe) and Siberia lay off to the southeast. Africa and South America had not yet formed, but various bits and pieces were spread out in a long arc on the west side. Australia and India were probably to the north or northwest. The position of other cratons is even less well known.

Rodinia was ripped apart during the Early Neoproterozoic (Tonian) by the Grenville Orogony, which left enormous amounts of volcanic rock on many of today's continents. Rodinia was surrounded by a single ocean, called the Iapetus Ocean or Sea. Towards the end of the Proterozoic, this supercontinent fragmented, giving rise to the late Ediacaran continents of Pannotia, Siberia, and North China. From Pannotia in turn came the diverse continents of Laurentia, Gondwana, and Baltica.

The second link provided gives a good visualisation of the break up of the supercontinent through geological time.

Answer 3

There are a couple very good answers already posted here.

Think of earths crust as moving around a lot over a period of time.

For simplicity we will say the surface of the earth is broken into crust plates that slide around.

This for various reasons spin of the earth, gravitational affects of the sun and moon, earth's core shifting and so forth.

For example:
Billions of years ago in the beginning there was very little land or dry land above the surface of the "waters".

Take a Rubik's cube and color the whole thing blue and half of one square brown.
(We know the earth is somewhat spherically egg shaped)

As the more "land" rose above the water over time more of these squares are brown.

Now, today, about one-third of them are brown.

Each one of these squares can be moved. Over time these squares have lumped together in different formations in various sizes. These are continents or super continents.

Sometimes there is formed a large group of them connected together by more than one side (square of Rubik's cube illustration) and these are super continents.

The last time these plates were all connected the formation is name "Pangaea" about 250 million years ago.

Pan means "all" like the airline Pan Am meant All America
Gaea means earth.

I personally like to use "Terra" for Earth.

One day in the distant future all of the plates will again shift to be connected and these could be called "Panterra". What a hoot.

Answer 4

There is a difference between Techtonic plate dynamics and continental drift. The plate activity is current, historic, measurable and predictable, so it qualifies as real threoy.
Continental drift and the super continent, on the other hand, is a supposition proposed by a scientist in the mid twehtieth century, repudiated and somehow was then restored to legitimiacy because of some later circumstantial evidence.
It is yet a highly speculative ,evolution- influenced idea, like the Big Bang.

Answer 5

It's speculation that the earths land mass was 1 piece.

Answer 6

Around 225 million years ago, the Earth was just ONE big continent.

Most commonly, paleogeographers employ the term supercontinent to refer to a single landmass consisting of all the modern continents. The earliest known supercontinent was Vaalbara.


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In reverse-chronological order (stratolithic order) comprising nearly all land at the time.

Pangaea Ultima or Amasia (~250 – ~400 million years from now (future supercontinent))
Austro-Antarctica-Eurafrasia (~130 million years from now (future supercontinent))
Austro-Eurafrasia (~60 million years from now (future supercontinent))
Eurafrasia (~30 million years from now (future supercontinent))
Americas (~ 15 mya present-day supercontinent)
Eurasia (~ 60 mya present-day supercontinent)
Gondwana (~600 – ~30 million years ago)
Laurasia (~ 300 – ~60 million years ago)
Pangaea (~300 – ~180 million years ago)
Euramerica (~ – ~300 million years ago)
Pannotia (~600 – ~540 million years ago)
Rodinia (~1.1 Ga – ~750 million years ago)
Columbia, also called Nuna, (~1.8–1.5 Ga ago)
Kenorland (~2.7 Ga. Neoarchean sanukitoid cratons and new continental crust formed Kenorland. Protracted tectonic magna plume rifting occurred 2.48 to 2.45 Ga and this contributed to the Paleoproterozoic glacial events in 2.45 to 2.22 Ga. Final breakup occurred ~2.1 Ga.)
Ur (~3 Ga ago, though probably not a supercontinent; but still however, the earliest known continent. Ur, however, was probably the largest, perhaps even the only continent three billion years ago, so one can argue that Ur was a supercontinent for its time, even if it was smaller than Australia is today). Still an older rock formation now located in Greenland dates back from hadean
Komatii Formation (3.475 Ga)
Vaalbara (~3.6 Ga ago. Evidence is the Yilgarn Craton, Western Australia and the world-wide Archean greenstone belts that were subsequently spread out across Gondwana and Laurasia)
Yilgarn (Zircon crystals from the Jack Hills of the Narryer Gneiss Terrane, Yilgarn craton, Western Australia and also 300 km. south point to a continental crust formation between 4.4-4.3 Ga. Evidence is the high Oxygen-18 values of 8.5 and micro-inclusions of SiO2 in these zircon crystals consistent with growth from a granitic source supracrustal material, low-temperature interactions and a liquid ocean.)

It formed from proto-continents and was a supercontinent by 3.1 billion years ago (3.1 Ga). Vaalbara broke up ~2.8 Ga.

Answer 7

there are two periods pangea which broke up 250 ish million years ago
and Rodinia, 1 billion years ago

Answer 8

the theory of plate tectonics says there were several supercontinents , and each broke up before they collided and formed the next.

try this length for info http://www.scotese.com/earth.htm

1100 million years ago was the first

Answer 9

very very very very very very long ago! did you know there used to hippo in the river severn in the UK