Page 199 - Laboratory Manual in Physical Geology

A CTIVIT Y 6.5 Sediment Analysis, Classification, and Interpretation

Name: ______________________________________ Course/Section: ______________________ Date: ___________
Complete parts 1 through 6 for each sample below. Refer to FIGURES 6.2 and 6.3 as needed.

SAMPLE A

1. Grain size range in mm: _______________________________________________
0 1 mm

2. Percent of each Wentworth size class:
clay _______ silt _______ sand _______ gravel _______
3. Grain sorting (circle):
Poor Moderate Well
4. Grain roundness (circle):
Angular Subround Well-rounded
5. Sediment composition (circle):
Detrital Biochemical Chemical
(Siliciclastic) (Bioclastic)
Ooids

6. Describe how and in what environment ( FIGURE 6.10 ) this sediment may have formed.

SAMPLE B
0 1 2 mm
1. Grain size range in mm: __________________________________________

2. Percent of each Wentworth size class:
clay ____ silt ____ sand ____ gravel ____
3. Grain sorting (circle):
Poor Moderate Well
4. Grain roundness (circle):
Angular Subround Well-rounded
5. Sediment composition (circle):
Detrital (Siliciclastic) Biochemical (Bioclastic) Chemical

6. Describe how and in what environment ( FIGURE 6.10 ) this sediment may have formed.

SAMPLE C
0 10 mm 1. Grain size range in mm: __________________________________________

2. Percent of each Wentworth size class:

clay _______ silt _____ sand ____ gravel ____
3. Grain sorting (circle):
Poor Moderate Well
4. Grain roundness (circle):
Angular Subround Well-rounded
5. Sediment composition (circle):
Detrital Biochemical Chemical
(Siliciclastic) (Bioclastic)
6. Describe how and in what environment ( FIGURE 6.10 ) this sediment may have formed.

D. REFLECT & DISCUSS Imagine that these sediments

are rocks. Which of the samples do you think would be the
least diagnostic of a specific ancient environment? Why?
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