Abstract ........................................................ 1
Introduction .................................................... 1
The Upwelling Model ............................................. 1
Stratigraphy and Definitions .................................... 3
Shallow Marine Deposits of the Phosphoria Sea in Nevada ......... 3
Northern and Central Nevada .................................. 3
1. Leach Mountains ....................................... 3
2. Southern Pequop Mountains ............................. 3
3. Ferber Hills .......................................... 4
4. Confusion Range ....................................... 4
5. Elk Mountain .......................................... 5
6. Northern Snake Mountains .............................. 5
7. Southern Snake Mountains .............................. 5
8. Medicine Range ........................................ 6
9. Butte Mountains ....................................... 6
10. Mount Ichabod ......................................... 6
11. Dorsey Canyon-Divide Peak ............................. 6
12. Northern Adobe Range .................................. 7
13. Peko Hills ........................................... 10
14. Southern Adobe Range ................................. 11
15. Southern Piñon Range ................................. 11
16. Edna Mountain ........................................ 11
17. Monitor Range ........................................ 12
18. Southern Toiyabe Range ............................... 12
19. Southern Toquima Range ............................... 12
20. Candelaria Hills ..................................... 12
Southern Nevada ............................................. 13
The Allochthonous Havallah Sequence ......................... 14
21. Battle Mountain ...................................... 14
22. Southern Shoshone Range .............................. 14
23. Northern Toiyabe Range ............................... 15
Western Correlatives of the Havallah Sequence ............ 15
24. Northern Hot Springs Range ........................... 15
25. Northern East Range .................................. 16
Correlatives of the Phosphoria Formation in Terranes
Thought to be Accretionary .................................. 16
26. Quinn River Crossing ................................. 16
27. Pine Forest Range .................................... 16
Conclusions .................................................... 16
The Phosphoria Sea and Its Sediments in Nevada .............. 16
Pennsylvanian and Permian Strata Underlying Sediments of
the Phosphoria Sea in Nevada ................................ 17
The Phosphate Content of Phosphoria-age Sediments in
Nevada ...................................................... 17
The Western Margin of the Phosphoria Sea .................... 17
Phosphoria Formation and the Oceanic Upwelling Model ........ 17
Acknowledgments ................................................ 17
References Cited ............................................... 17
Figures
1. Index map of Nevada, Idaho, and vicinity .................... 2
2-26.Photographs of:
2. Leach Mountains, Meade Peak Member; steinkern with part
of carbonate shell intact ................................... 3
3. Leach Mountains, Meade Peak Member, closely packed
pellets with interstitial quartz silt and carbonate ......... 4
4. Ferber Hills, Meade Peak Member, steinkerns and pellets
are cemented with clear secondary chert ..................... 4
5. Confusion Range, Plympton Formation, dolomite with
dispersed crystals and rosettes of gypsum ................... 5
6. Confusion Range, Plympton Formation, minute pellets and
masses of phosphate in fine-grained dolomite ................ 5
7. Confusion Range, Plympton Formation, spicule chert with
sparse, minute phosphate pellets ............................ 5
8. Mount Ichabod, slightly phosphatic spicule chert in
which most of the phosphate is in the axial canals of
the spicules ................................................ 6
9. Mount Ichabod, phosphatic sandstone ......................... 7
10. Dorsey Canyon, sandstone from unit 2 ........................ 7
11. Northern Adobe Range, lower member, prismatic shell of
Atomodesma in phosphatic limestone laced with length-
slow chalcedony ............................................. 8
12. Northern Adobe Range, middle member, spicule chert
showing dolomite rhombs and phosphate (dark brown) in
axial canals of spicules .................................... 8
13. Northern Adobe Range, top member, phosphatic pellets in
siltstone matrix of dolomite rhombs, quartz, and
spicules .................................................... 8
14. Northern Adobe Range, top member, small phosphatic
steinkerns in slightly phosphatic siltstone ................. 8
15. Peko Hills, middle unit, central pellet composed
largely of spicules with interstitial phosphate ............ 10
16. Peko Hills, middle unit, small pellets and ooides in
matrix of broken spicules and fragments of phosphatic
shells ..................................................... 10
17. Peko Hills, middle unit, steinkern with phosphate and
spicules in a matrix of silt-size quartz, spicules, and
phosphate .................................................. 10
18. Peko Hills, middle unit, bed of mainly gypsum and
length-slow chalcedony among clasts of phosphatic chert
and siltstone .............................................. 11
19. Southern Adobe Range, irregular phosphate pellets and
a steinkern in a matrix of angular quartz clasts,
spicules, and minute phosphate pellets ..................... 11
20. Edna Mountain, Edna Mountain Formation, two large
clasts of phosphate in a matrix of quartz, spiculitic
chert, and small phosphate clasts .......................... 12
21. Edna Mountain Formation, length-slow chalcedony clasts
in sandstone, here composed mainly of angular chert
grains ..................................................... 12
22. Candelaria Hills, Diablo Formation, phosphorite mass
composed of phosphate pellets in a matrix of quartz-
silty phosphorite .......................................... 13
23. Candelaria Hills, Diablo Formation ......................... 13
24. Battle Mountain, mid-Permian part of Havallah sequence,
small phosphate rods and pellets are in chert-cemented
quartz silstone ............................................ 14
25. Battle Mountain, mid-Permian part of Havallah sequence,
phosphate pellets are in a matrix mainly of spicules
and silt-size quartz and chert grains ...................... 14
26. Battle Mountain, mid-Permian part of Havallah sequence,
phosphatic sandstone ....................................... 15
Table
1. Percent P2O5 of samples chosen at arbitrary equal
intervals across mid-Permian stratigraphic units,
northern and southern Adobe Range ........................... 9
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