(Grain size, shape
SEDIMENTARY ROCK STUDY SHEET
6.6 SEDIMENTARY ROCK CLASSFICATION
Table 6.2 is a simplified classification scheme for sedimentary rocks based on texture and
mineralogy. First use texture to determine whether the rock is dominantly clastic, chemical, or biogenic
origin (Figure 6.8), the
Figure 6.6 Degree of grain roundness in clastic sedimentary rocks
a. A clastic sedimentary rock with rounded grains
b. A clastic sedimentary rock with angular grains
EXERCISE 6.3 RECOGNIZING SEDIMENT DEPOSITED BY STREAMS, WIND, AND GLACIERS
hematite and limonite and their silicon and oxygen are dissolved. In general, minerals formed at high
temperatures and pressures are most susceptible to chemical weathering. Those formed at conditions
closest to those of the surface are more resistant.
and the precise meaning of those terms is shown in Figure 6.4. You dont have to use a ruler to measure
the smaller clasts. If individual grains are visible with a hand lens, the clasts are at least sand-sized. If
you cant see grains, rub the rock (gently!
d. a mixture of quartz grains and clay minerals
e. rock fragments composed of calcic plagioclase feldspar and pyroxene
d. Which of the above rocks are mineralogically mature? Which are immature?
Why was weathering so different in the rocks in Exercise 6.1
Figure 6.15 Fossils reveal remarkable details of life throughout geologic time
a. Relatively fragile organisms
Fish from Green River shale, Wyoming
b. Relatively robust organisms
Program Chapter 10
Grading Information: This Program is due on Date Specified.
Comments are REQUIRED; flow charts and pseudocode are NOT REQUIRED.
The file must be called <LastFirstChapter10.java> (driver program)
Figure 6.12 Cross-bedding
a. Sand grains are deposited in inclined layers
on the down-current side of a ripple. As beds
accumulate, changes in wind or water direction
are indicated by the slope of the cross-beds.
b. Large-scale cross-bedding in sandstones
6.7 SEDIMENTARY STRUCTURES: CLUES TO PALEO-ENVIRONMENTAL CONDITIONS
Gravity causes all types of sediment to settle to the floor of the basin in which they are deposited.
Over time, layers of sediment (called beds) accumulate, ranging from a millimeter to