2020-05-08. Are We Seeing a New Ocean Starting to Form in Africa? By Erik Klemetti, Eos/AGU. Excerpt: ...The entire Afar region in eastern Africa finds itself in the middle of changes that could split the continent, forming a new ocean basin. The magmatism at Erta Ale might be offering signs of this switch by mimicking the characteristics of a mid-ocean ridge. ... What we will be able to see standing on top of Erta Ale will change dramatically in 5 million, 50 million, or 100 million years. The question is whether Erta Ale and the Afar region will become a new ocean, or whether ongoing tectonic collisions to Africa’s north and east will prevent this transition from occurring.... [https://eos.org/articles/are-we-seeing-a-new-ocean-starting-to-form-in-africa] 2017-02-17. Zealandia: Is there an eighth continent under New Zealand?
By BBC News.
2012 Feb 8. Next Supercontinent Will Form in Arctic, Geologists Say. By Sindya N. Bhanoo, The NY Times. Excerpt: Geologists have long predicted that North and South America will eventually fuse together and merge with Asia, forming a new supercontinent along the lines of the ancient Pangea — the precursor to today’s great land masses, which separated about 200 million years ago. In the past, researchers had guessed that the new continent, often called Amasia, would form either in the same location as Pangea, closing over the Atlantic near present-day Africa, or 180 degrees away, on the other side of the world. But a new study predicts that Amasia will form over the Arctic Ocean….
2010 Feb 27. Underwater Plate Cuts 400-Mile Gash. By HENRY
FOUNTAIN, NY Times. Excerpt: The magnitude 8.8
earthquake that struck off the coast of Chile early Saturday morning
occurred along the same fault responsible for the biggest quake ever
measured, a 1960 tremor that killed nearly 2,000 people in Chile and
hundreds more across the Pacific.
Both earthquakes took place along a fault
zone where the Nazca tectonic plate, the section of the earth’s crust
that lies under the Eastern Pacific Ocean south of the Equator, is
sliding beneath another section, the South American plate. The two are
converging at a rate of about three and a half inches a year.
Earthquake experts said the strains built up
by that movement, plus the stresses added along the fault zone by the
1960 quake, led to the rupture on Saturday along what is estimated to be
about 400 miles of the zone, at a depth of about 22 miles under the sea
floor. The quake generated a tsunami, with small surges hitting the
West Coast of the United States and slightly larger ones in Hawaii and
other parts of the Pacific. A 7.7-foot surge was recorded in Talcahuano,
Chile.
Jian Lin, a geophysicist with the Woods Hole
Oceanographic Institution, said the quake occurred just north of the
site of the 1960 earthquake, with very little overlap. “Most of the
rupture today picked up where the 1960 rupture stopped,” said Mr. Lin,
who has studied the 1960 event, which occurred along about 600 miles of
the fault zone and was measured at magnitude 9.5....
2008 May.The
Living Story of Sulawesi. by
Kathleen M. Wong, ScienceMatters@Berkeley.
Excerpt:
The Indonesian island of Sulawesi
is a 12,000-square-mile jigsaw
puzzle. During the past 25 million
years, drifting tectonic plates
tore four separate paleo-islands
from the far corners of the South
Pacific and smashed them together
in a steamy corner of Southeast
Asia.
This turbulent history has turned Sulawesi into a complex biological
cipher. Today, it houses a mélange of species with confusing
origins: some may have been passengers on the original islands,
some may have arrived afterward, and some may have evolved from
the mix.
...Jim McGuire, curator of herpetology at Berkeley's Museum of
Vertebrate Zoology and a professor of integrative biology, is
studying how these species evolved and came to be distributed
on Sulawesi today.
.."It was as if they were cut off from each other at some
point. But in many cases we don't know what the underlying mechanism
would be," McGuire says.
...Based on these data, he uses computer simulations to reconstruct
the evolutionary history of these animal groups. He then plans
to go back and study contact zones between species more closely
to try to identify any environmental or ecological barriers,
such as past flooding or the presence of a predator, that are
enforcing species isolation....
28 August 2007. A
Daddy Longlegs Tells the Story of
the Continents' Big Shifts. By
CARL ZIMMER, NY Times. Excerpt:
Few people have heard of the mite
harvestman, .... The animal is a
relative of the far more familiar
daddy longlegs. But its legs are
stubby rather than long, and its
body is only as big as a sesame seed.
... "They
look like grains of dirt," said
Gonzalo Giribet, an invertebrate
biologist at Harvard. ... Dr. Giribet
and his colleagues have spent six
years searching for them on five
continents. The animals have an
extraordinary story to tell: they
carry a record of hundreds of millions
of years of geological history,
chronicling the journeys that continents
have made around the Earth.
The Earth's land masses have slowly
collided and broken apart again several
times, carrying animals and plants
with them. These species have provided
clues to the continents' paths.
The notion of continent drift originally
came from such clues. In 1911, the
German scientist Alfred Wegner was
struck by the fact that fossils of
similar animals and plants could
be found on either side of the Atlantic.
The ocean was too far for the species
to have traveled themselves. Wegner
speculated - correctly, as it turned
out - that the surrounding continents
had originally been welded together
in a single landmass, which he called
Pangea.
Continental drift, or plate tectonics
as it is scientifically known, helped
move species around the world. Armadillos
and their relatives are found in
South America and Africa today because
their ancestors evolved when the
continents were joined. ...The 5,000
or so mite harvestmen species can
be found on every continent except
Antarctica. Unlike animals found
around the world like cockroaches,
mite harvestmen cannot disperse well.
The typical harvestman species has
a range of less than 50 miles. Harvestman
are not found on young islands like
Hawaii.
"It's really hard to find a
group of species that is distributed
all over the world but that also
don't disperse very far," said
Sarah Boyer, a former student of
Dr. Giribet, now an assistant professor
at Macalester College in St. Paul...
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