Table 3.

Total number of prokaryotes in unconsolidated subsurface sediments

Depth interval,* m	Cells/cm3, × 106	No. of cells, × 1028
		Deep oceans†	Continental shelf and slope‡	Coastal plains§
0.1	220.0¶	66.0	14.5	4.4
10	45.0¶	121.5	26.6	8.1
100	6.2¶	18.6	4.1	1.2
200	19.0¶	57.0	12.5	3.8
300	4.0¶	12.0	2.6	0.8
400	7.8¶		10.1	3.2
600	0.95‖		3.7	1.2
1,200	0.61‖		3.2	1.0
2,000	0.44‖		2.6	0.9
3,000	0.34‖			0.7
Total		275.1	79.9	25.3
Grand Total: 380 × 1028 = 3.8 × 1030

^*Depth intervals are designated by the upper boundary. Thus, “0.1” represents 0.1–10 m and “3,000” represents 3,000–4,000. 

^†Corresponds to seismic layer I (23). 

^‡Corresponds to subcontinental sediments (23). 

^§Corresponds to geosyncline sediments of Mesocenozoic origin (23). 

^¶Calculated from the arithmetic averages. 

^‖Calculated by extrapolation of the formula of Parkes et al. (33).