logo
Find us on
Twitter Facebook LinkedIn
              
logo 11/24/2024 10:48:46 PM     
Ice Age Canadian Lakes 
CA Source: earthobservatory 1/21/2022
Ice Age Canadian Lakes
The Manitoba Great Lakes—Winnipeg, Winnipegosis, and Manitoba— are smaller than their more famous Great Lake neighbors to the south, but they can claim more wetlands along their shores. Forty-three percent of the land area of the province of Manitoba, Canada, is covered by bogs, fens, marshes, swamps, and open shallow water.

The origins of the lakes and the wetlands can both be traced to the last ice age. The modern wetlands result from the region’s low-lying topography, which was leveled by advancing and retreating ice sheets. The three Manitoba Great Lakes, however, are actual remnants of glacial Lake Agassiz. This was an ice-dammed lake that formed south of the Laurentide Ice Sheet about 14,500 years ago. At its largest, Lake Agassiz was 1,125 kilometers (700 miles) long and 400 kilometers (250 miles) wide. As the ice dams melted and receded at the end of the ice age, about 8,000 years ago, outlets to the sea opened and the lake drained, leaving behind the deeper lakes we now call great.
 

The above image, acquired by the Operational Land Imager (OLI) on Landsat 8 on November 3, 2021, shows two of the three great lakes, along with Cedar Lake, in south-central Manitoba. (Note that Norman Kuring, a retired researcher from NASA’s Ocean Biology group applied color-filtering techniques to the image to draw out the fine details in the water. Those features are real but might not be as apparent to the unaided human eye.)

The colorful swirls in the relatively clear and shallow lakes—Lake Cedar’s maximum depth is about 10 meters (32 feet)—are likely due to suspended sediment and phytoplankton. The lakebeds are covered in fine-grained silt, clay, and calcium-carbonate sediments, which give some of the lakes their chalky blue hues. (Little Limestone Lake stands out.) The region is underlain by dolomite, a calcium-magnesium-carbonate rock similar to limestone that was deposited during the Paleozoic Era when the landmass was under a shallow, tropical sea.

 
Agassiz Lake Continue...

News Id SourceStampcountry
2826In Portugal, Taking a Dive Into Sardinesnytimes2022-07-13PT
2827Страсть и донная снастьОхотники.ру2022-07-24RU
2828Ловля судака на живцовые снастиОхотники.ру2022-07-25RU
2829На Алтае откроется межрегиональная выставка "Охота и рыболовство Алтая 2022"Рыболовство2022-07-25RU
2830US Could Require Steps for Dams to Save Last Atlantic SalmonAssociated Press2022-07-25US
2831Woman, 73, stabbed by 100-pound sailfish that leapt from water off Florida coastFox News2022-07-24US
2832Cod stock off southern N.L. coast at critical levels, says Fisheries Departmentctv news2020-11-20CA
2833Fisheries report brings hope to Indigenous communities, sparks anger in industryctv news2022-07-19CA
28344 Alberta men lose 80 pounds of halibut and crab, fined $4,500 after violations: B.C. conservation officersctv2022-07-22CA
2835Fisheries Department needs to think like a fishpenticton herald2022-07-23CA
2836Underwater robot connects humans' sight and touch to deep seatechxplore2022-07-21US
2837Get paid for catching snakeheads: Maryland tagging program pays up to $200 per fishFOX 5 DC2022-07-06US
2838Fish-farming practices come under scrutiny amid surge in aquaculturemongabay2022-07-06ID
2839Thousands of dead fish washing up along shores of Chesapeake Bay after fishing company reports torn netwtkr2022-07-02US
2840Florida woman kills fish by pouring hot sauce in tank during a fight, deputies sayFOX 35 News2022-07-07US
2841Fisherman caught with fish bombing paraphernalia in Sempornathestar2022-07-08US
2842Engineers try to electro shock invasive carpabc17news2022-07-08US
2843Study: Half of Great Lakes residents unaware of safe fish consumption limitswoodtv2022-07-05US
2844В жару за карпомОхотники.ру2022-07-23RU
2845Meet Australia’s oldest freshwater fish, which can breathe air like a land dwellersmh2022-07-07AU
2846Texas angler becomes first female high school fishing national championwashingtonpost2022-07-06US
2847Ringleader, 35, of illegal poaching operation who stole £60,000 worth of salmon and trout over seven years avoids jailMailonline2022-07-09UK
2848Climate Change May Be Causing Skin Tumors On Antarctic Fishnewsweek2022-07-04US
2849Changes in Gulf of Maine may endanger lucrative fish stocks, experts sayupi2022-07-08US
2850Кто живет в тихой речкеОхотники.ру2022-07-21RU

134 135 136 113 of [137 - pages.]