Imagine you are a geologist standing in front of a large outcrop of sandstone, shale, and limestone layers. It is your job
to determine the depositional environment(s) and paleogeographic history of the area. What are four pieces of information
needed to make a determination, and how will those pieces of information help you make a determination? Fill in the blank(s) with the appropriate word(s).
1. Order in which rocks were deposited gives you relative dates of facies, and climatic
conditions (marine regression or transgression)
2. Composition of rock, in combination with other factors, can tell you source area of
sediments (in case of sandstone) or narrow down environments (in case of limestone).
3. Textural properties such as grain size, sorting, and rounding can indicate the energy level
of the depositional environment, distance travelled, and/or the method of transport (wind or
water).
4. Sedimentary structures. Every depositional environment has unique processes that create
characteristic sedimentary structures like crossbeds, mud cracks, etc. that can be used for
identification.
5. Fossils. If organisms are fossilized where they lived, they can give geologists a wealth of
information about past environments.
6. Geometry of the rock layers can be useful in conjunction with other factors to determine
past depositional environments. Certain deposits have characteristic shapes.
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The scientific name of an organism includes the genus and species name
Indicate whether the statement is true or false
Watering and fertilizing plants in your home provides them with components of the
A) atmosphere and lithosphere. B) hydrosphere and biosphere. C) lithosphere and hydrosphere. D) biosphere and atmosphere.
Which of the following denaturing agents affects hydrophobic regions?
A) detergents B) heat C) heavy metals D) urea
Lakes and reservoirs undergo little vertical mixing because ____.
A. they are too warm B. rain accumulates in a layer of freshwater on the surface C. wind drives primarily horizontal mixing D. plant growth impedes flow E. they contain stratified layers