The 1.235 Ga ESE-trending Sudbury dyke swarm cuts Paleoproterozoic to Archean rocks,but at its SE end becomes deformed and metamorphosed by the;Ga Grenville orogen,a result of collision between Laurentia
The Greater Sudbury Area is approximately 400 km north of the city of Toronto and falls within a large number of temperate lakes of various sizes. This area has been mined for nickel and other metals for several decad...The Greater Sudbury Area is approximately 400 km north of the city of Toronto and falls within a large number of temperate lakes of various sizes. This area has been mined for nickel and other metals for several decades. These activities have affected the watersheds of Northern Ontario and have influenced the chemistry of a number of lakes. Blooms of cyanobacteria occur yearly in several lakes, mainly in the early and late summer months. Much of the chemistry of these lakes is known but the nature of the cyanobacterial blooms and the factors that may contribute to their sudden appearance are not. We sampled blooms from five Greater Sudbury Area lakes and identified the species present by morphological and molecular methods. The dominant genera present as characterized by morphological examination were Synechocystis, Leptolyngbya, Anabaena, Cyl-indrospermum, Nostoc, Borzia, Phormidium, Pseudoanabaena, Oscillatoria, and Planktothrix. Three of these isolates, Leptolyngbya, Anabaena, and Planktothrix were confirmed by partial rRNA sequence analysis.展开更多
During the maintained quiescence between solar cycle 23 and 24, two unusually intense (K-indices = 7) global geomagnetic disturbances separated by 6 days occurred. They were followed by a protracted increase of betwee...During the maintained quiescence between solar cycle 23 and 24, two unusually intense (K-indices = 7) global geomagnetic disturbances separated by 6 days occurred. They were followed by a protracted increase of between 150 and 200 nT in the vertical component of our local magnetic field (Sudbury, Ontario). The duration of the variation anomaly was unusually long, about 3 weeks, before returning to baseline following a one week period of below average intensity characterized by approximately 50 min periodicities. We suggest this anomaly supports previous research that specific temporal patterns of increased global geomagnetic activity when matched with local impedance/reluctance of ore bodies created the condition for remarkable transient changes in the surface static intensity of magnetic fields.展开更多
文摘The 1.235 Ga ESE-trending Sudbury dyke swarm cuts Paleoproterozoic to Archean rocks,but at its SE end becomes deformed and metamorphosed by the;Ga Grenville orogen,a result of collision between Laurentia
文摘The Greater Sudbury Area is approximately 400 km north of the city of Toronto and falls within a large number of temperate lakes of various sizes. This area has been mined for nickel and other metals for several decades. These activities have affected the watersheds of Northern Ontario and have influenced the chemistry of a number of lakes. Blooms of cyanobacteria occur yearly in several lakes, mainly in the early and late summer months. Much of the chemistry of these lakes is known but the nature of the cyanobacterial blooms and the factors that may contribute to their sudden appearance are not. We sampled blooms from five Greater Sudbury Area lakes and identified the species present by morphological and molecular methods. The dominant genera present as characterized by morphological examination were Synechocystis, Leptolyngbya, Anabaena, Cyl-indrospermum, Nostoc, Borzia, Phormidium, Pseudoanabaena, Oscillatoria, and Planktothrix. Three of these isolates, Leptolyngbya, Anabaena, and Planktothrix were confirmed by partial rRNA sequence analysis.
文摘During the maintained quiescence between solar cycle 23 and 24, two unusually intense (K-indices = 7) global geomagnetic disturbances separated by 6 days occurred. They were followed by a protracted increase of between 150 and 200 nT in the vertical component of our local magnetic field (Sudbury, Ontario). The duration of the variation anomaly was unusually long, about 3 weeks, before returning to baseline following a one week period of below average intensity characterized by approximately 50 min periodicities. We suggest this anomaly supports previous research that specific temporal patterns of increased global geomagnetic activity when matched with local impedance/reluctance of ore bodies created the condition for remarkable transient changes in the surface static intensity of magnetic fields.
