Featured Research

from universities, journals, and other organizations

Clinker geochronology, the first glacial maximum, and landscape evolution in the northern Rockies

Date:
June 28, 2011
Source:
The Geological Society of America
Summary:
Scientists have developed and successfully carried out a novel, extraordinary technique for learning how efficiently river channels cut and increase local topographic relief: They have used the exposure of "clinker" deposits in combination with highly refined dating techniques.

Peter W. Reiners of the University of Arizona and colleagues have developed and successfully carried out a novel, extraordinary technique for learning how efficiently river channels cut and increase local topographic relief: They have used the exposure of "clinker" deposits in combination with highly refined dating techniques.

Clinkers are baked coals; baking naturally occurs in shallow depths (tens of meters) and when the clinkers are exhumed during erosion and the development of topographic relief, they are resistant and the rate of exposure can be timed using the U-Th/He isotopic system found in zircons within the clinkers.

In this application, the Reiners and colleagues determined aspects of the pace of recent evolution of Powder River Basin in northern Wyoming and southern Montana. Ages of in-situ clinkers range from as old as 1.1 million years to as young as 10,000 years, but most formed in one of the last three interglacial periods, reflecting either changes in fluvial downcutting caused by glacial-interglacial cycles or other climatic effects on rates of natural coal burning. Clinker deposits atop a broad terrace in the northern part of the Powder River Basin provide a maximum age of 2.6 plus or minus 0.2 million years for terrace formation.

This corresponds to the onset of major Northern Hemisphere glaciation interpreted from marine records, suggesting that the terrace formed by lateral erosion of the landscape as rivers were overwhelmed with sediment during the earliest Plio-Pleistocene glacial episode. The overall correlation of clinker ages with elevation above local base level suggests generally increasing incision and topographic relief in the Basin over at least the last one million years, at rates of ~0.1-0.3 km/million years.


Story Source:

The above story is based on materials provided by The Geological Society of America. Note: Materials may be edited for content and length.


Journal Reference:

  1. Peter W. Reiners, Catherine A. Riihimaki, Edward L. Heffern. Clinker geochronology, the first glacial maximum, and landscape evolution in the northern Rockies. GSA Today, 2011; 4 DOI: 10.1130/G107A.1

Cite This Page:

The Geological Society of America. "Clinker geochronology, the first glacial maximum, and landscape evolution in the northern Rockies." ScienceDaily. ScienceDaily, 28 June 2011. <www.sciencedaily.com/releases/2011/06/110628094820.htm>.
The Geological Society of America. (2011, June 28). Clinker geochronology, the first glacial maximum, and landscape evolution in the northern Rockies. ScienceDaily. Retrieved July 23, 2014 from www.sciencedaily.com/releases/2011/06/110628094820.htm
The Geological Society of America. "Clinker geochronology, the first glacial maximum, and landscape evolution in the northern Rockies." ScienceDaily. www.sciencedaily.com/releases/2011/06/110628094820.htm (accessed July 23, 2014).

Share This




More Earth & Climate News

Wednesday, July 23, 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