Featured Research

from universities, journals, and other organizations

Tibetan Plateau may be older than previously thought

Date:
August 16, 2012
Source:
Penn State
Summary:
The growth of high topography on the Tibetan Plateau in Sichuan, China, began much earlier than previously thought, according to an international team of geologists who looked at mountain ranges along the eastern edge of the plateau.

Mountains near the Tibetan plateau.
Credit: alexnika / Fotolia

The growth of high topography on the Tibetan Plateau in Sichuan, China, began much earlier than previously thought, according to an international team of geologists who looked at mountain ranges along the eastern edge of the plateau.

The Indian tectonic plate began its collision with Asia between 55 and 50 million years ago, but "significant topographic relief existed adjacent to the Sichuan Basin prior to the Indo-Asian collision," the researchers report online in Nature Geoscience.

"Most researchers have thought that high topography in eastern Tibet developed during the past 10 to 15 million years, as deep crust beneath the central Tibetan Plateau flowed to the plateau margin, thickening Earth's crust in this area and causing surface uplift," said Eric Kirby, associate professor of geoscience at Penn State. "Our study suggests that high topography began to develop as early as 30 million years ago, and perhaps was present even earlier."

Kirby, working with Erchie Wang of the Institute of Geology and Geophysics at the Chinese Academy of Sciences in Beijing; Kevin Furlong, professor of geosciences at Penn State; and colleagues from Waikato University, New Zealand and Arizona State University, looked at samples taken from the hanging wall of the Yingxiu-Beichuan fault, the primary fault responsible for the 2008, Wenchuan earthquake. The researchers used a variety of methods including the decay rate of uranium and thorium to helium in the minerals apatite and zircon and fission track dating, an analysis of tracks or trails left by decaying uranium in minerals again in apatite and zircon.

"These methods allow us to investigate the thermal regime from about 250 degrees Celsius (482 degrees Fahrenheit) to about 60 degrees (140 degrees Fahrenheit)," said Kirby. "The results show that the rocks cooled relatively slowly during the early and mid-Cenozoic -- from 30 to 50 million years ago -- an indication that topography in the region was undergoing erosion."

The results also suggest that gradual cooling during this time was followed by two episodes of rapid erosion, one beginning 30 to 25 million years ago and one beginning 15 to 10 million years ago that continues today.

"These results challenge the idea that the topographic relief along the margin of the plateau developed entirely in the Late Miocene, 5 to 10 million years ago," said Kirby. "The period of rapid erosion between 25 to 30 million years ago could only be sustained if the mountains were not only present, but actively growing, at this time."

The researchers also note that this implies that fault systems responsible for the 2008 earthquake were also probably active early in the history of the growth of the Tibetan Plateau.

"We are still a long way from completely understanding when and how high topography in Asia developed in response to India-Asia collision," notes Kirby. "However, these results lend support to the idea that much of what we see today in the mountains of China may have developed earlier than we previously thought."

The Chinese National Key Projects Program, the National Natural Science Foundation of China and the National Science Foundation funded this research.


Story Source:

The above story is based on materials provided by Penn State. Note: Materials may be edited for content and length.


Journal Reference:

  1. E. Wang, E. Kirby, K. P. Furlong, M. van Soest, G. Xu, X. Shi, P. J. J. Kamp, K. V. Hodges. Two-phase growth of high topography in eastern Tibet during the Cenozoic. Nature Geoscience, 2012; DOI: 10.1038/ngeo1538

Cite This Page:

Penn State. "Tibetan Plateau may be older than previously thought." ScienceDaily. ScienceDaily, 16 August 2012. <www.sciencedaily.com/releases/2012/08/120816101029.htm>.
Penn State. (2012, August 16). Tibetan Plateau may be older than previously thought. ScienceDaily. Retrieved July 22, 2014 from www.sciencedaily.com/releases/2012/08/120816101029.htm
Penn State. "Tibetan Plateau may be older than previously thought." ScienceDaily. www.sciencedaily.com/releases/2012/08/120816101029.htm (accessed July 22, 2014).

Share This




More Earth & Climate News

Tuesday, July 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

New Orleans Plans to Recycle Cigarette Butts

New Orleans Plans to Recycle Cigarette Butts

AP (July 21, 2014) New Orleans is the first U.S. city to participate in a large-scale recycling effort for cigarette butts. The city is rolling out dozens of containers for smokers to use when they discard their butts. (July 21) Video provided by AP
Powered by NewsLook.com
Shark Sightings a Big Catch for Cape Tourism

Shark Sightings a Big Catch for Cape Tourism

AP (July 21, 2014) A rise in shark sightings along the shores of Chatham, Massachusetts is driving a surge of eager vacationers to the beach town looking to catch a glimpse of a great white. (July 21) Video provided by AP
Powered by NewsLook.com
Spectacular Lightning Storm Hits London

Spectacular Lightning Storm Hits London

AFP (July 19, 2014) A spectaCular lightning storm struck the UK overnight Friday. Images of lightning strikes over the Shard and Tower Bridge in central London. Duration: 00:23 Video provided by AFP
Powered by NewsLook.com
A Centuries' Old British Tradition Is Far from a Swan Song

A Centuries' Old British Tradition Is Far from a Swan Song

AFP (July 19, 2014) As if it weren't enough that the Queen is the Sovereign of the UK and 15 other Commonwealth realms, she is also the owner of all Britain's unmarked swans. Duration: 02:18 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins