Question

using the stratigraphic section and photographs located in the textbook (chapter 7 investigation), determine the environment of deposition for the dark gray shale (there is one correct answer).

Answer 1

The dark gray shale in the stratigraphic section indicates a deep marine or swamp environment, as the black color suggests the absence of oxygen during deposition. Other factors, such as lithology and fossil content, should also be considered to determine the environment accurately.

Step-by-step explanation:

The dark gray shale in the stratigraphic section is indicative of a deep marine or swamp environment. The black color of the shale suggests that there was no oxygen present during deposition. This is supported by the fact that the color of sedimentary rocks is largely determined by the amount of oxygen available during burial and lithification.

It is important to note that the color of sedimentary rocks may not always accurately represent the environment of deposition, as the conditions affecting buried sediment may not always match the surface environment. Therefore, it is necessary to consider other factors, such as lithology and fossil content, to accurately determine the depositional environment.