Virtual Field Study
The first step in collecting geologic field data from an outcrop is to examine the outcrop and make observations. These preliminary observations provides geologists with the data they need to study how organisms and environments change over time. Common observations taken at outcrops includes the type of rocks present, the thickness of the layers, the identification of sedimentary features (bedding, ripple marks, bioturbation), grain size, color, paleocurrent indicators, and fossil content. These observations may also include an examination of the outcrops "attitude," (the orientation of beds), by measuring the strike and dip of the beds with a compass. All of these observations provide us with information we can interpret as we try to determine the depositional environment of a sedimentary rock layer, for example, the water depth, species composition, paleogeography, and climate at the time it formed.
Last modified October 06 2008 03:01 PM