Deltas Amazon

Michalopoulos, P. and Aller, R. C. (1995). Rapid clay mineral formation in Amazon Delta sediments reverse weathering and oceanic elemental cycles. Science 270, 614-617. 

This seemed an unusual number of coincidences and so I pressed my search. Consultation with the almanac of the Naval Observatory brought a real surprise. On the very day that I was researching, December 22, 1973, a total, annular eclipse of the sun would occur and the path of totality would sweep directly across La Chorrera and the Amazon Basin. I was dumbfounded. I felt like a person in a novel this string of clues was actually real I researched the eclipse to determine exactly where it would achieve totality. This would occur, I learned, almost directly over the city of Belem in Brazil, in the delta of the Amazon River. The vertiginous elf chatter of hyperspace rose squealing in my ears. Was it mocking me or egging me on ... 

The meaning of this dream was far from clear at the time, and even now it remains obscure. What is clear is that at a given date an event of importance was to be expected in the delta of the Amazon. I hoped then that the total eclipse of the sun was that long-anticipated event, and that its totality over the vagina of the world mother anticipated an event of great import for everyone. 

Euxinic and semi-Euxinic Amazon delta (marine C) Amazon delta (terrestrial C) Mississippi delta (marine C)... 

Michalopoulos, P., and Aller, R.C. (2004) Early diagenesis of biogenic silica in the Amazon Delta alteration, authigenic clay formation, and storage. Geochim. Cosmochim. Acta 68, 1061-1085. 

Area subject to flooding estimated from geomorphological maps derived from the SLAR imagery occupies about 78,000 km along the Amazon mainstem and an additional 62,000 km along the lower reaches of the four major tributaries (Sippel et al. 1992 52.5 W to 70.5-W, reaches 1 through 12). Islands comprise a small proportion of the total main-stem floodplain, except in the Amazon delta which is excluded from our... 

A) Total lignin phenol yield per 100 mg of organic carbon (L) versus delta for Amazon mainstem samples (C=CPOM, F=FPOM, and D=UDOM) and potential source materials, and... 

Amazon deltaic deposits are reworked extensively by tides and waves (Geyer et al. 1996, Kineke et al. 1996, Sternberg et al. 1996). Over 10% of the Amazon subaqueous delta is covered by fluid muds (suspended solid concentration > 10 g L O, which can be several meters thick in some places. These sediments and the water contained therein can be mobilized by changes in frontal dynamics or by fortnightly tidal cycles (Kineke et al. 1996, Geyer et al. 1996). Even in nonfluid mud areas, the sediment can be... 

If additional terrigenous POC reaches the Amazon shelf as a result of human aaivity, approximately one third of it will be buried in the delta, one tenth will be transported out of the system, and the remainder will be... 

Amazon Delta, eastern equatorial Atlantic eastern equatorial Pacific Long Island Sound Mississippi Delta Northwest African continental margin Pacific deep sea Pern continental margin Santa Barbara Basin western Gulf of Mexico (includes data sets from references 2, 3, 5, and 6 from Sholkovitz, (1973),... 

This reaction shows that reverse weathering is exactly opposite to continental weathering reactions, which consume C02 and liberate I ICO, (see Section 4.4.3). Experimental studies with Amazon delta sediments in the mid 1990s have provided the first evidence that reverse weathering reactions occur naturally. The K+ sink in Amazon continental shelf sediments alone is calculated to be 6.8 X 1012 gyr-1, representing about 10% of the annual global K+ river flux to the oceans. 

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