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Descriptions available in the Common Ground Database

Ball Chocolade SS (ball_chocolate_ss)

 
Added:2000/-0/5-
Changed:2000/-0/5-
ball_chocolate_ss_1 (image/jpeg)
ball_chocolate_ss_2 (image/jpeg)
  Dominantly quartz grains, with some heavily altered feldspar grains.
Grain size 150 Microns, well sorted, subrounded.
Overgrownth illite and smectite cements.
Porosity 22.5%.

ball_chugwater_ss

 
Added:2000/-0/5-
Changed:2000/-0/5-
ball_chugwater_ss_1 (image/jpeg)
ball_chugwater_ss_2 (image/jpeg)
  Dominantly quartz and Potassium feldspar grains.
Grain size 20 microns, moderate to well sorted, angular to subangular.
Extensive zeolite (clinoptilolite) cement.
Bubble-textured mineral may be thomsonite.
Cubical minerals may be clinoptinolite and laumonite, all zeolites.
Porosity 18.1%.

ball_gold_ss

 
Added:2000/-0/5-
Changed:2000/-0/5-
ball_gold_ss_2 (image/jpeg)
ball_gold_ss_1 (image/jpeg)
  Almost entirely quartz grains, some with pitting.
Grain size 150 microns, well sorted, subrounded.
Quartz cement, with some sharp overgrowth quartz cements present.
These suggest a phase of quartz leaching, with later pressure solution cementation.
Porosity 17.6%.

ball_woodbine_ss

 
Added:2000/-0/5-
Changed:2000/-0/5-
ball_woodbine_ss_1 (image/jpeg)
ball_woodbine_ss_2 (image/jpeg)
  Grains are almost entirely quartz.
Grain size 75-100 microns, well sorted, subrounded.
Cement is mostly quarts. Some Kaolinite present within cement.
Porosity 32.4%

Berea GS Plate 2a

 
Added:1999/-0/1-
Changed:2000/-0/4-
berea_gs_plate2a (image/jpeg)
  Homogeneously distributed grains of quartz (white), feldspar (Cl5+), and rock fragments
(Fl) dominate the framwork of this moderately sorted, fine-grained sandstone.
Intergranular pores also apear homogeneously distributed between adjacent framework grans.
Cements, however, appear heterogeneously distributed.
(25X, plane-polarized light)

Berea GS Plate 2b

 
Added:1999/-0/1-
Changed:2000/-0/4-
berea_gs_plate2b (image/jpeg)
  Oversized secondary pores (E-F7-8, J-K12-13, C-D11-12) appear more homogeneously
distributed relative to the Berea RPL sample.
Ankerite cements (G13, G-H11-12) also are more evenly scattered.
A sutured grain contact is shown at C3. (50X, plane-polarized light)

Berea RPL Plate 1a

 
Added:1999/-0/1-
Changed:2000/-0/4-
berea_rpl_plate1a (image/jpeg)
  A general view of this unoriented to vaguely laminated, questionably
size-graded, fine-grained sandstone shows a predominantly quartzose
framework which has been locally cemented by undifferentiated matrix
(C14-15), quartz (E3-4), ankerite (F-G10), pyrite (J-K9-10), and kaolinite
(E-F7). Microporosity is associated with the authigenic kaolinite. (25X,
plane-polarized light)

Berea RPL Plate 1b

 
Added:1999/-0/1-
Changed:2000/-0/4-
berea_rpl_plate1b (image/jpeg)
  This close-up view shows that secondary pores (E-F8-9, A-B12-13) and
ankerite cements (J-K6-7, J-K11) appear heteroneneously distributed,
whereas other, probably primary intergranular pores (B1, E14) and
quartzose framwork grains (white) appear homogeneously distributed. No
fractures were observed in this sample. (50X, plane-polarized light)

Tenn SS Plate 3a

 
Added:1999/-0/1-
Changed:2000/-0/4-
tenn_ss_plate3a (image/jpeg)
  A relatively non-porous region of this slightly oriented, moderately
sorted, fine-grained sandstone (upper two-thirds of photomicrograph)
appears adjacent to a relatively porous region of the sample (lower third
of photomicrograph). Relatively non-porous areas have probably been
produced by compaction and suturing during burial. Homogeneously
distributted, quartzofeldspathic grains form the major portion of the
framework of this sample. (25X, plane-polarized light).

Tenn SS Plate 3b

 
Added:1999/-0/1-
Changed:2000/-0/4-
tenn_ss_plate3b (image/jpeg)
  Pore isolation (F-G9-10, J11-12, J-K6-7, E14) has been produced by
compaction and grain suturing. Most of these isolated pores are probably
secondary, having been formed by the partial to complete leaching of
framework grains such as feldspar. (50X, plane-polarized light)

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