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USEFUL FACTS CONCERNING THE EARTH

‘^’ means ‘to the power of’
pi - 3.14159; e = 2.718228; Surface area of a sphere - 4piR^2
1 gram = 10^-3 kg; = 10^-6 megagrams (tonnes); 10^-9 gigagrams; = 10^-12 teragrams (Tgrams); = (femto);=  (atto).
1 gram = 10^3 milligrams; = 10^6 micrograms; = 10^9 nanograms; = 10^12 picograms
1 kg = 10^3 grams; = 10^-3 tons; = 10^-9 Tgrams
1 kg = 10^6 milligrams = 10^9 micrograms = 10^12 nanograms = 10^15 picograms
1 litre = 10^3 millilitres (ccs) = 10x10x10 decametres = 10^-12 km^3 (1 km^3 = 10^12 litres)
1 short ton =.907184 tonnes; 1 long ton = 1.0160469 tonnes
1 ppm = 1 kg / 10^6 kg or 1 gram / 10^6 grams, etc.; = 1 mgram/kg.

Atomic mass, major elements: Si - 28.09; Ti - 47.88; Al - 26.98; Fe - 55.85; Mg - 24.31; 
Ca - 40.08; Na - 22.99; K - 39.1; P - 30.97; oxygen - 16; Cl - 35.45; carbon - 12.01; S - 
32.07
Concentration - micromoles/litre = 10^-6 moles/litre = 10^-9 moles/millilitre
(Mass concentration = Atomic mass x micromoles/litre x 10^-9 kg/kg;
e.g. Ca, 558000 x 35.45 x 10^-9 = 0.0198 kg/kg)
Concentration  - millimoles/litre = 10^-3 moles/litre = 10^-6 moles per millilitre
(Mass concentration, e.g. Mg, = 54 x 24 x 10^-6 = .00129 kg/kg)

                        Equatorial radius				6,378.137 km
                        Polar radius					6,356.752 km
                        Equivolume sphere radius			6,371 km (4 pi R^2)
                        Surface area					5.1 x 10^8  km^2
                        Circumference					40,030 km (2 pi R)
                        Mass, M						5.97369 x 10^24 kg
                        Mean Density					5.5148 x 10^3 kg / m^3
                        Density of continental crust			2.7500 x 10^3 kg / m^3
                        Gravity at equator				9.7803267 m / s^2
                        Gravity at poles				9.832186 m / s^2
                        Mean land elevation				825 m
                        Mean ocean dept					3,770 m
                        Depth of ridge crests below sea level		2,500 m
                        Area of oceans excluding continental margins	3. 1 x 10^8 km^2
                        Land area of continental crust			1.48 x 10^8 km^2
                        Continental crust plus continental margins	2 x 10^8 km^2
                        Average thickness of continental crust		38 km
                        Average thickness of oceanic crust		6 km
                        Volume of continental crust 			7.6 x 10^9 km^3
                        Volume of continental sediments on ocean floors	1.6 x 10^8 km^3
                        Age of the Earth				4.5 Ma
                        Total length of active ocean ridges		56,000 km
                        Average rate of prod, oceanic crust (Mes. - Cen.) 25 km^3 /yr
                        Present day production of oceanic crust		17 km^3 /yr
                        Ave product / km of ridge length (Mes. - Cen.)	450 km^3 /km /Ma
                        Total length of destructive margins		37,000 km
                        Average velocity of subduction			80 km /Ma
                        Ave subduction rate / km of margin (Mes. - Cen.) 675 km^3 /km /Ma

Average area of the oceans is 3.6 x 10^8 km^2 = c. 71% of the surface of the Earth.
Volume of rain water entering the oceans from rivers   4 x 10^16 kg = 4 x 10^4 km^3

Calculated surface of oceans at 71% of 5.1 x 10^8:	3.62 x 10^8 km^2
Calculated volume of the oceans if depth is 3.73		1.354 x 10^9 km3
Calculated surface of the continents at 29%:		1.479 x 10^8

The following data may be consulted in:
Berner, E.K. and Berner, R.A., 1987 The Global Water Cycle. Prentice 
Hall, N.J., 397p.
Berner, E.K. and Berner, R.A., 1996 Global Environment. Prentice 
Hall, 376p.
Open University Course Team, 1992 Seawater. its composition, 
properties and behaviour. Open University and Pergamon Press.
Open University Course Team, 1989 The Ocean Basins. their structure 
and evolution. Open University and Pergamon Press, 171 p.
Open University course team, 1989 Ocean Chemistry and Deep-sea 
sediments. Open University and Pergamon Press, 134 p.
Pinet, M. 1996. Oceanography.

Water Reservoirs  10^6 km^3
Oceans		1370	97.25
Ice masses	29	2.05
Groundwater	9.5	0.68	
Lakes		0.125	0.01
Atmosphere	0.013	0.001
Rivers		0.0017	0.0001
Biosphere	0.0006	0.00004

Precip on land		110300
Evap from land 		72900
Water entering rivers 	37400 (4 x 10^4 km^3/yr)
Precip on oceans	385700
Evap from oceans	423100
Total precip		496000
Total evap		496000

Salt
Surface area of the Earth = 4piR2 = (4 x 3.1416 x (6378)^2) km^2 = 5.1119 x 10^8 km^2
Continental area = 4piR2  x 0.29 = (4 x 3.1416 x (6378)^2) km^2 x 0.29 = 1.4824 x 10^8 km^2
Ocean area = 4piR2 x 0.71  =  (4 x 3.1416 x (6378)^2) km^2 x 0.71 = 3.6294 x 10^8 km^2
Ratio of oceanic area to continental area = 2.4483
   1 m = 100 cm;		1 km = 1000 m;
   1 l = 1000 cm^3  = 1 dm^3	1 km^3 = 109 m^3 = 10^12 dm^3 (litres) = 10^12 kg (SG = 1)	
Ocean volume = 4piR2  x depth x %ocean surface = 4 x 3.1416 x (6378)2  x  3.73 x 0.71 
= 1.354x10^9 km^3. (S x 4 x 0.71 km^3 =  S x 2.8 km^3)
SG of seawater is 1.0265 at 5oC and salinity of 35, and therefore mass of sea water = 
1.354x 10^9 x 1.0265 x 10^12 kg = 1.39 x 10^9  x 10^12 kg
(S x 4 x 0.71 x 1 x 10^12 kg = S x 2.8 x 10^12) 
Salt (all principal ions) content of sea water is .035 kg/kg of seawater)
therefore total mass of salt is .035 x 1.39^24 x 10^21 kg  = 4.86 x 10^19 kg
                                             (S x 4 x 0.71 x 1 x 10^12 x .035 kg = S x 0.1 x 10^12)
and since SG of salt is c. 2.17
the total volume of salt = 4.74 x 10^19 x 1 x 10^-12 / 2.17 = 2.224 x 10^7 km^3 
                                       (S x 4 x 0.71 x 1 x .035 / 2 km^3 = S x 0.05 x 10^12)

If all the salt in the oceans were spread over only the continents, its thickness would be:
 (2.224 x 107) / (1.4824 x 108) km = 151 m.
Calculated another way using approximations, where S is the surface area of the Earth, 
the salt thickness would be:
(Surface area of the Earth x oceanic prop x depth of oceans  x salt conc. x SG of sea 
water x SG salt) / (Surface area of the Earth x continent proportion) = (S x 0.71 x 4 x 1 
x 0.035 / 2) / (S x 0.29) km = 0.05 / 0.3  = c. 0.165 km = 165 metres.

The calculated thickness is similar to the estimate of 500 feet (170 m) of Swensen
(If the salt in the sea could be removed and spread evenly over the Earth's land surface it 
would form a layer more than 500 feet thick, .. salty.ref)

If the salt were spread over the whole of the Earth, its thickness would be :
(2.184 x 107 / 5.10101 x 108 x 1000) metres = 44 metres

The thickness in the oceans only would be (2.184 x 107 km^3 / 3.63 x 108 x 1000) metres = 61 metres

Lithsphere is 250 km thick under the continents.
Lithosphere is 100 km thick under the oceans.
	
Maximum height - 8.5 km
Average height = 0.8 km
Averge depth of sea - 3.7 km
Maximum depth - 11.04
21% of earth's surface lies between sea level and 1 km
23.2% lies between 4 - 5 km depth

			Pacific	Atlantic	Indian	World Medit.
Oceanic area 10^6,	180	107	74	361	2.5
Land area drained 10^6	19	69	13	101
Ocean/drainage area 	9.5	1.6	5.7	3.6
Average depth, km	3.94	3.31	3.84	3.73	1.5
Ave volume					1.346x10^9 km^3
						 = 1.345x10^21 litres
Ave mass (Vol x 1.0265)				1.382x10^21 kg
Area as % of total:
Mid-ocean ridges, % 	35.9	31.2	30.2	32.7
Trenches, %		2.9	.7	.3	1.7
Shelf and slope, %	13.1	19.4	9.1	15.3
Rise, %			2.7	8.5	5.7	5.3
Abyssal deeps, %		42.9	38.1	49.3	41.9
Volcanic edifices, %	2.5	2.1	5.4	3.1

Meditteranean
Surface area  - 2.5 10^ km^2
Average depth 1.5 km
Volume 3.75 x 10^6 km^3
Amount of salt = 3.75 x 10^6 x 10^12 x .035 = 1.3 x 10^17 kg
Area of the floor of the Meditteranean - 2 x 10^6 km^2
Equivalent thicknes of salt - 32.8 m
Thickness of salt in the Miocene Messinian deposits - 1 km
Loss of water from the Mediterranean by evaporation - 4.7 x 10^3 km^3
Precipitation in the Medit. - 1.2 x 10^3 km^3
Rivers contribute to the Med - 0.25x10^3 km^3
Net loss through precipitation - 3.25 x 10^3 km^3, made up by addition of Atlantic water.
Time to dry up if no replacement = 1.15 x 10^3 years

Hydrothermal vent solution at c. 350 deg.C at 21N on the East Pacific Rise, ppm by weight;
pH of the vent solution is 4.0 whereas normal seawater is about 8.
If 1.7 x 10^14 kg of seawater circulates through th oceanic crust each year and if it picks 
up 460 ppm (460 ppm = 4.60 x 10^-4 kg / kg) then 7.8 x 10^10 kg of Ca is added to the 
seas, compared with 5 x 10^11 kg introduced from rivers.
	vent			seawater	
	,ppm			,ppm
Cl	17300 = 0.0173 kg/kg	19500 = 0.0195 kg/kg
Na	9931 =   0.0099 kg/kg	10500 = 0.0105 kg/kg
Mg	 -			1290 =   0.00129 kg/kg
SO42-	 -			905
H2S	210			 -
Ca	860			400
K	975			380
Sr	8			8
Si	600			3
Ba	5-13			2x10^-2
Zn	7			5x10^-3
Mn	33			1x10^-4
Fe	101			2x10^-4

Sediments		Atlantic	Pacific	Indian	World
Calcareous ooze		65.1	36.2	54.3	47.1
Pteropod ooze		2.4	0.1	 -	0.6
Diatom ooze		6.7	10.1	19.9	11.6
Radiolarian ooze	 -	4.6	.5	2.6
Pelagic clay		25.8	49.0	25.3	38.1
Rel % size of ocean	23	53.4	23.6	100

Ratio of illite to quartz = 4, except South Pacific = 7
Illite: N Atlantic 60; S. Atlantic 50; North Pacific 40; Indian 35; S. Pacific 28

	Concentration	Total Amount
	in the oceans	in the oceans
	 ppm		tonnes (1 tonne = 10^3 kg)
Cl	 1.95x10^4	2.57x10^16	Cl-
Cl	 0.0195 kg/kg	2.57x10^19 kg
Na	 1.077x10^4	1.42x10^16	Na+
Mg	 0.129	"	0.71	"	Mg2+
Ca	 0.0412	"	0.0545	"	Ca2+
K	 0.038	"	0.0502	"	K+
S	 0.0905	"	0.12	"	SO42- (= 2.7 ppm)
Br	67		8.86x10^13	Br-
Br	67x10^-6 kg/kg	8.86x10^16 kg
C	28		3.7		HCO3-, CO32-, CO2
N	11.5		1.5		N2, NO3-, NH4+
Sr	8		1.06
O	6		7.93x10^12
B	4.4		5.82
Si	2		2.64
P	6x10^-2		7.93x10^10	HPO42-, PO43-, H2PO4-
P	6x10^-8 kg/kg	7.93x10^13
Ti	1x10^-3		1.32x10^9	Ti(OH)4
Al	4x10^-4		5.29x10^8	Al(OH)4-
Al	4x10^-10 kg/kg	5.29x10^11 kg
Mn	1		1.32		Mn2+, MnCl+
Cu	1		1.32
Fe	5.5x10^-5 	7.26x10^7
Zr	3		3.97
Nb	1		1.32
Be	5.6 x10^-6 	7.4 x10^6
Au	4	"	5.29		AuCl2-
La	3	"	3.97		La(OH)3
Nd	3	"	3.97
Pb	2	"	2.64
Ce	1	"	1.32
Y	1.3	"	1.73
Yb	8x10^-7		1.06
Sm	5x10^-8		6.61x10^4
Eu	1		1.32

Ave % of 10 most abundant elements in the Earths crust, wt %, compared with 
seawater, kg/kg or kg/litre):
Element		Crust		In seawater	% in solution
Si		28.2
Al		8.2
Fe		5.6
Ca		4.2		0.000412 kg/kg	 1.7
Na		2.4		0.01076		74.7%
K		2.1		0.000387	 3.1
Mg		2.3		0.001294	
Ti		0.6
Mn		0.1
P		0.1

Dissolved substance in river water, ppm
Bicarbonate	58.8	5.88 x10^-5 kg/kg	48.7%
Ca2+		15	1.50 x10^-5 kg/kg	12.4
SiO2		13.1	1.31 x10^-5 kg/kg	10.8
SO42-		1.2	1.20 x10^-6 kg/kg	9.3
Cl		7.8	7.80 x10^-6 kg/kg	6.5
Na+		6.3	6.30 x10^-6 kg/kg	5.2
Mg2+		4.1	4.10 x10^-6 kg/kg	3.4
K+		2.3	2.30 x10^-6 kg/kg	1.9
NO3-		1.0	1.00 x10^-6 kg/kg	0.8
(Fe,Al)2O3	0.9	9.00 x10^-7 kg/kg	0.8
Remainder	0.3	3.00 x10^-7 kg/kg	0.3

Photic zone rarely extend below 200m of the ocean
3/4 of organic matter in sinking particles that leave the photic zone are decomposed and 
recycled in the upper 500-1000 m of the water column.
At the compensation depth the oxygen produced by phytoplankton during 
photosynthesis equals the amount they consume in respiration over a 24 hour period.

Concentration - micromoles/litre = 10^-6 moles/litre = 10^-9 moles/millilitre
(Mass concentration = Atomic mass x micromoles/litre x 10^-9 kg/kg;
e.g. 558000 x 35.45 x 10^-9 = 0.0198 kg/kg)
				
Component	River	Seawater	Tau(r) (1000 yr)
		Water
Cl-		230	558,000	(=0.0198 kg/kg)	87,000
Na-		315 	479,000			55,000
Mg--		150	54,300			13,000
S04--		120	28,900			8,700
Ca++		367	10,500			1,000
K+		 36	10,400			10,000
HCO3-		870	2,000			83
H4SIO4		170	100			21
NO-3		 10	20			72
Orthoph- 	 0.7	1			50
osphate
Tau(r) = ([SW]/[RW])Tau(w), where Tau(w) = replacement (residence) time of H2O = 
36,000 yr; RW = river water; SW = seawater, and concentration in micromoles per litre 
= VtM.

 Major Processes of Organic Matter Decomposition in Marine Sediments.
Reactions succeed one another in the order written as each oxidant is completely
consumed
Oxygenation (oxic)

	CH2O + 02  =  CO2 + H2O

	Nitrate reduction (mainly anoxic)

	5CH2O + 4NO3-   =  2N2 + CO2 + 4HCO3- + 3H2O

	Manganese oxide reduction (mainly anoxic)

	CH2O + 2MnO2 + 3CO2 + H2O = 2Mn++  + 4HCO3-

	Ferric oxide (hydroxide) reduction (anoxic)

	CH2O + 4Fe(OH)3 + 7CO2 = 4Fe++ + 8HCO3- + 3H2O
	Sulfate reduction (anoxic)
	2CH2O + SO4- -   =   H2S + 2HCO3-
	Methane formation (anoxic)
	2CH2O = CH4 + CO2

Note: Organic matter schematically represented as CH2O.

Concentration Changes of Some Major Seawater Constituents Upon 
Reacting with Basalt at High Temperatures
Concentration (a mM = a millimoles/litre = a x 10^-3 moles/litre = a x 10^-6 moles per 
millilitre, and e.g. concentration in kg/kg of Mg = 54 x 24 x 10^-6 = .00129 kg/kg)
	Constituent       Seawater Galapagos  Delta (mM)
	Mg++		54	0	- 54
	Ca++		10	35	  25
	K+		10	19	   9
	SO4--		29	0	- 29
	H4SiO4		0.1    	~20	 ~20
	Delta Ca++ minus
	Delata S04--	-	-	  54
Note: mM = ~millimoles per liter.						
	Data are for the Galapagos spreading center at 350C and are taken from the 
extrapolation of Edmond et al. (1979).
Delta  = concentration difference between 350' C ~Galapagos water and ~seawater.
Delta Ca++ minus Delta S04-- = total Ca++ released to solution.

Change in Concentration in Interstitial Water for Various Ions versus
Depth in a Sediment from the Brazil Basin, South Atlantic Ocean (Station CH 1 1 ~5-
DD)
	Sediment Concen 	Change - Pore Water Overlying Seawater (mM)
	Depth	 -tration
	(cm)	pH		DNa+	DMg++	DCa++	DK+	DHCO3- DS04--

	0	7.4		0.00	 0.00	0.00	 0.00	0.00	 0.00
	5	7.5		0.07	-0.04	0.17	-0.05	0.19	 0.05
	15	7.3		0.09	-0.35	0.45	-0.11	0.25	 0.04
	30	7.5		0.46	-0.42	0.50	-0.08	0.34	 0.06
	60	7.5		0.45	-0.58	0.76	-0.11	0.68	 0.06
	100	7.2		0.56	-0.78	0.97	-0.16	0.82	-0.01
	195	7.4		0.95	-1.09	1.18	-0.26	1.12	-0.13
Note: Negative Delta values refer to uptake by the sediment (loss from pore water).
mM = millimoles per litre; = 10^-3 moles per litre.

Rates of Addition via Rivers of Major Elements to the Ocean (as Dissolved Species)
and Rates of Net Loss from the Ocean by Transfer of Sea Salt to the 
Continents via the Atmosphere
		Rate of Addition	Rate of Net Sea Salt Loss
	Species	from Rivers, (Tg/yr)	to Atmosphere (Tg/yr)
	Cl-		308		40
	Na+		269		21
	S04- - -S	143		4
	Mg++		137		3
	K+		52		1
	Ca++		550		0.5
	HCO3-		1980		--
	H4SiO4-Si	180		--
	Tg = 1012 g. Based on river water input of 37,400 km3/yr; includes 
pollution.

The Oceanic Chloride Budget (Rates in Tg/yr)
Present-Day Budget
				Inputs				Outputs
	Rivers (natural)	215	Net sea-air transfer	40
	Rivers (pollution)	93	Pore-water burial	17
	Total			308	Total			57

Long-Term (Balanced) Budget
			Inputs				Outputs
	Rivers		215	NaCl evaporative
				deposition		166
				Net sea-air transfer	40
				Pore-water burial	9
				Total			215
Note:	Tg = 1011 g. Replacement time for Cl- is 87 million years.

The Oceanic Sodium Budget (Rates in Tg/yr)
Present-Day Budget
				Inputs					Outputs
	Rivers (natural)	193		Cation exchange		42
	Rivers (pollution)	76		Net sea-air transfer	21
						Pore-water burial	11
	Total			269		Total			74

Long-Term Budget
		Inputs							Outputs
	Rivers	193				NaCl deposition		 108
						Net sea-air transfer	 21	
						Cation exchange		 21
						Pore-water burial	 6
						Basalt-seawater reaction 37
						Total			193
Note: Tg  = 1012 g. Replacement time for Na+ is 55 million years.

The Oceanic Magnesium Budget (Rates in Tg/yr)
 (Balanced) Budget for Past 100 Million Years
			Inputs				Outputs

	Rivers		137	Volcanic-seawater
				reaction		119
				In biogenic CaCO3	15
				Net sea-air transfer	3
				Total			137
Note:	Tg = 1012 g. Replacement time for Mg++ is 13 million years.

The Oceanic Potassium Budget (Rates in Tg/yr)
Long-Term (Balanced) Budget
			Inputs					Outputs
	Rivers		52	Fixation on clay
				near river mouths		4
	Volcanic-seawater	Sea-air transfer		1
	reaction (high-
	temperature	30
	Total		82	Low-temperature volcanic-
				seawater reaction or
				slow fixation in deep
				sea or reverse weathering	77
				Total				82
Note:	Tg = 1012 g. Replacement time for K+ is 10 million years.

The Oceanic Calcium Budget (Rates in Tg/yr)
Present-Day Budget
			Inputs				Outputs
	Rivers		550	CaCO3 deposition:
	Volcanic-seawater	Shallow water		520
	reaction	191
	Cation exchange	 37	Deep sea		440
	Total		778	Total			960

Budget for Past 25 Million Years
			Inputs				Outputs
	Rivers		550	CaCO3 deposition:
	Volcanic-seawater	Shallow water		240
	reaction	191	Deep sea		440
	Cation exchange	 19	Evaporitic CaSO4
				deposition		 49
	Total		760	Total			729
	Note: Tg = 1012 g. Replacement time (rivers only) for Ca is 1 million years.

The Oceanic Bicarbonate Budget (Rates in Tg/yr)
Present-Day Budget
			Inputs				Outputs
	Rivers		1980	CaCO3 deposition:
	Biogenic pyrite		Shallow water		1580
	formation	 145
				Deep sea		1340
	Total		2125	Total			2920

Budget for Past 25 Million Years
			Inputs				Outputs
	Rivers		1980	CaCO3 deposition:
	Biogenic pyrite		Shallow water		730
	formation	145
				Deep sea		1340
	Total		2125	Total			2070
Note: Tg =1012 g. Replacement time for HCO3- (river input only) is 83,000 years.

The Oceanic Silica Budget (Rates in Tg/yr).
Present-Day Budget
			Inputs				Outputs
	Rivers		180	Biogenic silica deposition:
	Basalt-seawater		Antarctic Ocean		117
	reaction		30	Bering Sea	13
	Total		210	North Pacific Ocean	7
				Sea of Okhotsk		7
				Gulf of California	5
				Walvis Bay		3
				Estuaries		38
				Other areas		<13
				Total			190-203
Tg =  1012g. To convert to Tg of SiO2, multiply by 2.14. The replacement time 
for riverborne H4SIO4 is 21,000 years.  The removal value for estuaries may be a 
maximum.

The Oceanic Phosphorus Budget (Rates in Tg/yr)
Present-Day Budget
				Inputs				Outputs
	Rivers:				Dispersed authigenic P   1.0
	Natural dissolved P		Organic P burial	 2.2
	(organic plus ~ortho-P)	1.0	CaCO3 deposition	 0.1
	Dissolved P from		Adsorption on volcano-
	pollution		1.0	genic Fe oxides		 0.7
	Particulate reactive P		Phosphorite formation	<0.1
	(mostly pollution)	3.0
	Rain (plus dry			Fish debris deposition	<0.02
	fallout)		0.3
	Total			5.3	Total			 4.0

Long-Term (Balanced) Budget
				Inputs				Outputs
	Rivers:				Dispersed authigenic P  1.0
	Dissolved ortho-P	0.4	Organic P burial	1.1
	Dissolved organic P	0.6	CaCO3 deposition	0.1
					Adsorption on volcano-
	Particulate reactive P	1.5	genic Fe oxides		0.7
	Rain (plus dry fallout)	0.3	Phosphorite formation	0.1
	Total			2.8	Total			3.0		
Tg = 1012 g. The replacement time for phosphorus via river addition (of 
dissolved orthophosphate only) is 50,000 years.

The Oceanic Nitrogen Budget (Rates in Tg/yr)
Present-Day Budget
				Inputs					Outputs
	Rivers:					Organic N burial in
						sediments		14
	Natural dissolved			Denitrification		40- 120
	inorganic N (88% as			Total			54- 134
	NO3- -N)		     4.5
	Natural dissolved
	organic N		     10
	Pollutive dissolved N	      7
	Particulate organic N	     21
	Rain and dry deposition	     20
	Fixation of N2		   10-90
	Total			   73-153
Note:	Tg = 1012 g. The replacement time for NO3- added by rivers is 72,000 years.

FIGURES

Figure 1. Plate Tectonics.

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