Sentences with phrase «ice deposits during»
«Based on the likely location of ice deposits during this period of Mars» history, and the amount of meltwater that could have been produced by Lyot ejecta landing on an ice sheet, we think this is the most plausible scenario for the formation of these valleys» said David Weiss, a recent Ph.D. graduate from Brown and the study's lead author.
https://www.sciencedaily.com/ Not exact matches
The tools were found beneath glacial deposits laid down during a period 450,000 years ago when the region was blanketed in ice, so they must be older than this.
Their findings indicated that twice as much soot was deposited on snow in winter compared with summer, meaning that the sunlight - absorbing soot likely caused greater melting of the Arctic ice cap during the winter.
The latter events left behind distinctive rock - sequences typically consisting of tillites (ancient boulder - clay, now solid rock) representing ice - deposited debris, overlain with a depositional break by cap - carbonates (chemical sediments of marine origin deposited during interglacials following global sea - level rises).
The Capital Region largely sits on clay and silt deposited by a lake that swallowed the area during the last Ice Age, said Andrew Kozlowski, an associate state geologist at the State Museum and director of the state Geologic Mapping Program.
It was formed during the ice age when the prevailing winds transported the vast quantities of sand from New South Wales and deposited it along the coast of Queensland, forming the island as we know it today.
A boulder deposited by a glacier during the last ice age sits atop Cadillac Mountain in Acadia National Park, Maine.
The scientists were particularly interested in crystals found in layers deposited during the «Little Ice Age,» approximately 300 to 500 years ago, and during the «Medieval Warm Period,» approximately 500 to 1,000 years ago.
The clues found in sediments deposited during the late Holocene suggest that an ocean current that circles the southern polar region, known as Circumpolar Deep Water, flowed underneath the Cosgrove Ice Shelf and melted it.
The amount of detrital petrological tracers transported by icebergs and deposited in the ice - rafted debris belt (an Atlantic region between 40 - 50 ° N) greatly increases during episodes of southward and eastward advection of cold surface waters and drift ice from the Nordic and Labrador seas (Bond et al., 2001; figure 48 A).
«Basically our research showed how much ice was lost during summer and how much snow was deposited in the high regions,» Mayer said.
Imputities are a main problem in Greenland ice cores where a mix of seasalt / carbonate and acidic dust from Icelandic volcanoes can produce CO2 in situ, but is less of interest in deep inland Antarctic ice cores, except during the deepest times of glacials, when far more dust is deposited.
Higher levels of sea salts favor reduction processes and thus GEM destruction in the snow interstitial air (30), but no long - term trends have been reported for sea salt impurities deposited on the Greenland ice sheet during the last century (33).
The latter events left behind distinctive rock - sequences typically consisting of tillites (ancient boulder - clay, now solid rock) representing ice - deposited debris, overlain with a depositional break by cap - carbonates, chemical sediments of marine origin deposited during interglacials following global sea - level rises.