From top to bottom: Rounded tan domes of the Navajo Sandstone, layered red Kayenta Formation, cliff-forming, vertically jointed, red Wingate Sandstone, slope-forming, purplish Chinle Formation, layered, lighter-red Moenkopi Formation, and white, layered Cutler Formation sandstone.Photo from Glen Canyon National Recreation Area, Utah.Those are ordered and received well after a ship gets home from the deployment, or at least they used to.
Other examples of cross crutting relationships can be related to faults fault has to be younger than the rock it is found in and unconformities see below..
Relative dating is the science of determining the relative order of past events (i.e., the age of an object in comparison to another), without necessarily determining their absolute age, (i.e. In geology, rock or superficial deposits, fossils and lithologies can be used to correlate one stratigraphic column with another.
Prior to the discovery of radiometric dating in the early 20th century, which provided a means of absolute dating, archaeologists and geologists used relative dating to determine ages of materials.
The rock layer E is younger than D because it cuts through D and is the top layer of rock.
Ocean crossing certificates are not official Navy issue; most commands either make up their own (just a sheet with an emblem and info that may or may not get entered into your service record), or order printed and embossed ones from special commercial companies (Tiffany Publishing is a favorite).