Tuesday, November 17, 2015

Geology Field Camp Part 3

At field camp the geology student must apply many aspects of their education to the their field experience. From the basics learned in Geology 101 up to your senior year geophysics class or rock-forming processes (mineralogy). All those seemingly heterogeneous lessons begin congealing into this huge mass of knowledge that helps you to put geology, and more importantly, geologic processes into perspective. You are literally armed with tonnes of info to glean from so that when you go out into the field, you are able to piece major structures, rock units, mineralogy, and other visual keys within the rocks to 'tell' you their story.

This might sound easy, however it was much harder than one can expect. Despite your best efforts in trying to interpret what you are seeing in the rock,  there is always that voice in the back of your head asking you "are your sure?", "did you forget anything?", or "do you even know what it is your are looking at?" The latter being the most annoying for sure. The insecurity of a new geologist in training is numerous to say the least. We all second-guessed ourselves, and other students we were teamed up with. Questions or doubts as to what you observed and what your partners observed can be quite different at times. It may be as little as not seeing/missing a certain contact between rock units,  taking a bad bearing (reading), or placing your colluvium and alluvium in the wrong places on your field map.

What is she talking about? All these crazy-sounding words? Well to help you out if you are not a geology person here are a few brief definitions that I hope helps.

contact: where two very different rock layers or formations make contact with each other.
bearing: a reading off a compass (we use something called a Brunton with is a compass with lots of other tools to take measurements of rocks and contacts).
colluvium: is basically the rock debris found at the base of slopes or on slopes that weather from the rock unit(s) above. Other words for colluvium is scree and talus slope or talus accumulation. The biggest differences depends on materials (homogeneous or heterogeneous, and whether or not water was involved in their placement).
alluvium: debris that is usually the size of gravel or smaller that was deposited by some type of fluid/water flow.

Okay enough with the Webster's lesson. While I was mapping our Antelope Mountain project, which was a five-day project east of Eureka, Nevada, we came across many areas that really challenged our skills. The key to making sense of what contacts and structures we saw was what we wrote down in our field book (a geologists' notebook). Note-taking for geologists is an extensive process because we are looking for so many details of the rocks that lay before us. Of course, in writing our field notes we go back to all those classes from undergrad and upper level courses to ensure we get every piece of information we can from our observations.
Example of Theodolite cellphone camera picture taken at one of many Lake Lahontan sites we visited near the end of our summer field camp.

One part of grading on all of our mapping projects were our notebooks. All I can say is that is it NOT easy to keep your field book looking beautiful and clean...and when you are OCD like me, it is downright traumatic. Equipment is so important to geology and we rely on many tools that help us to read the rocks of our wonderful planet. The best advice I can give to any undergrad geology students in their first or second year at college is to start saving your change. You will be able to save enough to help you start building your field pack with the right equipment.
Fourth day of Antelope Summit mapping project was a bit of a wash(out) as it rained so heavy for a day and a half that we had difficulty getting our vans and trucks back into the area...and you thought the Nevada desert was brown and ugly. This is located in eastern Nevada just east of the town of Eureka, NV.

You can take all the knowledge given to you, and have all the right equipment in your field pack, but always remember that the best tools that will help when you later as you put your project reports together is your field note. Take pictures with your cell phone (and always carry a ruler to show scale) in addition to your field notes. There are even a couple of cool cell phone apps you can get that work well for field work, e.g., Theodolite, Google Earth, Geotimescale 2, etc. Although as you start getting yourself ready for your senior field camp school, the best advice is not to wait until the last minute to put a field pack together...and always carry a lot of water.