Think about a modern coastal lagoon with mudflats that are alternately submerged and exposed each day by rising and falling tides
With this environment and tidal processes in mind, what clues would you look for to identify the deposits of an ancient lagoon in the geologic record? How would you distinguish an ancient coastal lagoon mudstone from a floodplain deposit, where mud collects during river floods?
What will be an ideal response?
Mud and organic-rich sediment are common to both coastal lagoons and floodplains. Both environments are alternately wet and dry, so the rocks may contain mud cracks. However, lagoons may contain marine fossils while floodplain fossils would be terrestrial plant and animals. If there is cross-bedding, it would show transport in two different directions in the coastal lagoon, associated with the incoming and outgoing tide.
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The time for an oscillating system to make a vibration is its
A. wavelength. B. amplitude. C. frequency. D. period.
Instructions: Choose one answer from each pair of selections. The Younger Dryas that lasted from approximately 13,000 y.a. to 10,000 y.a. produced a WARM | COLD spell
Give four categories of consumers in an ecosystem and the role that each plays
What will be an ideal response?
Which of the following is a valid description of features within continental interiors?
A) The central region of a continent is called a shield and is a broad, basaltic volcano with gentle slopes. B) The continental platform has nearly horizontal sedimentary rocks deposited on crystalline basement. C) The oldest exposed rocks in a continent are usually along the coastline. D) Broad domes and basins in continental interiors have nearly vertical beds around their flanks. E) All of these are correct.