Scioly.org

JCicc wrote:Anybody on here take the SE PA geomapping exam? I'm interested in your feedback.

I did! It was well done, I think. I felt that the difficulty and range of questions were nicely challenging.

JCicc wrote:Anybody on here take the SE PA geomapping exam? I'm interested in your feedback.

I did as well. I thought that the content was fairly well balanced, and that the test was well organized. As for content, it seems about right, but I would be interested to see what other test writers come up with!

OMG, Cicc wrote a Geomaps test :OOO. Can't imagine what a states Geomaps test from you would be XD. Gah, states in a week...at least I feel like I've known more than my past years hopefully.

I was looking at the Yale Invitational, and I couldn't figure out how to solve a few questions.

Can anyone help me/give a few pointers?

Here are the questions:
1. A bed dips at an angle of 35 degrees east. The surface of the ground is level, and

the distance between the upper and lower contacts of the bed measured at right

angles to strike is 200 feet. Find the thickness of the bed. Draw a diagram and show

all work.

2. Along a railroad cut, a bed has an apparent dip of 35 degrees in a direction of

N30W. The bed strikes N50E. Using the trig solution technique, find the true dip.

Show all work.

I believe I just don't understand how to APPLY the concepts well enough to solve these questions!
I understand what dip and strike are- but my application of those two concepts is limited to simple problems, nothing like this!
Furthermore, does anyone have any tips on resources for learning stereonet techniques? I looked up some YouTube videos but they were rather confusing, to say the least.
As I have a week of vacation from classes, I believe this will be my last chance to have a serious study session, so if anyone can recommend any overall good sites for representative geological mapping (essentially the topographical map interpretation, profiling, FINDING FLOODING RISK (how do I do this?! are the places that are most vulnerable just the ones with lowest contour interval?), contour interval drawing, and stereonet technique, that would be sweet! For some reason, geology and abstract/memorization for the non-representative sections of GeoMapping come easy for me, but I just can't seem to study well for the representative parts- so I'm looking for more resources that are intuitive or simply interpretative in ANY WAY.

Help is GRATEFULLY appreciated, especially with state competitions coming up!
Thanks!

BipolarEconomist wrote:I was looking at the Yale Invitational, and I couldn't figure out how to solve a few questions.

Can anyone help me/give a few pointers?

Here are the questions:
1. A bed dips at an angle of 35 degrees east. The surface of the ground is level, and

the distance between the upper and lower contacts of the bed measured at right

angles to strike is 200 feet. Find the thickness of the bed. Draw a diagram and show

all work.

2. Along a railroad cut, a bed has an apparent dip of 35 degrees in a direction of

N30W. The bed strikes N50E. Using the trig solution technique, find the true dip.

Show all work.

I believe I just don't understand how to APPLY the concepts well enough to solve these questions!
I understand what dip and strike are- but my application of those two concepts is limited to simple problems, nothing like this!
Furthermore, does anyone have any tips on resources for learning stereonet techniques? I looked up some YouTube videos but they were rather confusing, to say the least.
As I have a week of vacation from classes, I believe this will be my last chance to have a serious study session, so if anyone can recommend any overall good sites for representative geological mapping (essentially the topographical map interpretation, profiling, FINDING FLOODING RISK (how do I do this?! are the places that are most vulnerable just the ones with lowest contour interval?), contour interval drawing, and stereonet technique, that would be sweet! For some reason, geology and abstract/memorization for the non-representative sections of GeoMapping come easy for me, but I just can't seem to study well for the representative parts- so I'm looking for more resources that are intuitive or simply interpretative in ANY WAY.

Help is GRATEFULLY appreciated, especially with state competitions coming up!
Thanks!

It's hard to explain via text, but I'll try.

For question 1, it's basic trigonometry.The bed intersects the ground surface and that means that the thickness that you see isn't the true thickness. That distance that you measure is called the apparent thickness.Now, you can make a right triangle, with the apparent thickness as the hypotenuse. You know the dip angle and you know the hypotenuse, and you want to find the opposite site of the angle, so you just do sin (dip angle) = opposite/apparent thickness.

It would be a lot easier if I could draw a picture for you, but hopefully you understand what I'm describing.

As for number 2, I never totally understood apparent dip, so I can't help you there.

So a question related less on content and more on the binder... How does everyone organize theirs? We are having trouble finding information quickly if we don't know it and we can't seem to find a way to organize it all easily...

fozendog wrote:So a question related less on content and more on the binder... How does everyone organize theirs? We are having trouble finding information quickly if we don't know it and we can't seem to find a way to organize it all easily...

I would strongly recommend tabbing the sides and color coding can also be useful in moderation. With our binder, I have general topics marked. In competition, if I'm looking for info on faults, I can flip to the section on geologic structures and from there find my specific notes. It's more of being familiar with your own organizational style than anything else

BipolarEconomist wrote:I was looking at the Yale Invitational, and I couldn't figure out how to solve a few questions.

Can anyone help me/give a few pointers?

Here are the questions:
1. A bed dips at an angle of 35 degrees east. The surface of the ground is level, and

the distance between the upper and lower contacts of the bed measured at right

angles to strike is 200 feet. Find the thickness of the bed. Draw a diagram and show

all work.

2. Along a railroad cut, a bed has an apparent dip of 35 degrees in a direction of

N30W. The bed strikes N50E. Using the trig solution technique, find the true dip.

Show all work.

I believe I just don't understand how to APPLY the concepts well enough to solve these questions!
I understand what dip and strike are- but my application of those two concepts is limited to simple problems, nothing like this!
Furthermore, does anyone have any tips on resources for learning stereonet techniques? I looked up some YouTube videos but they were rather confusing, to say the least.
As I have a week of vacation from classes, I believe this will be my last chance to have a serious study session, so if anyone can recommend any overall good sites for representative geological mapping (essentially the topographical map interpretation, profiling, FINDING FLOODING RISK (how do I do this?! are the places that are most vulnerable just the ones with lowest contour interval?), contour interval drawing, and stereonet technique, that would be sweet! For some reason, geology and abstract/memorization for the non-representative sections of GeoMapping come easy for me, but I just can't seem to study well for the representative parts- so I'm looking for more resources that are intuitive or simply interpretative in ANY WAY.

Help is GRATEFULLY appreciated, especially with state competitions coming up!
Thanks!

In response to the second question, there is quite a lengthy derivation, but it all boils down to this formula:

tan(true dip) = tan(apparent dip)/sin(angle between strike and trend of apparent dip)

Hello!

Im' wondering whether has any links to GeoMap tests, (or something that comes relatively close) I cant find any on the test exchange.

ReBobville wrote:Hello!

Im' wondering whether has any links to GeoMap tests, (or something that comes relatively close) I cant find any on the test exchange.

Do you know of http://www.soinc.org/trial_events? On that website there's a link to two practice tests (they're fairly similar). I will be honest in saying I've found many tests different from those, but there's some similarities I guess. If you mean others, I think there's maybe another one or two online somewhere. The issue is you may know that lots of invites don't want people putting up tests online and whatnot...and then seems like not many either understand the event enough or want to make a test to put up on the test exchange XD.

That said, if you have other questions I would try to at least respond. Noting that, I forgot to respond to a bunch of questions that sort of have already been! Oops...

The trigonometric method of approaching apparent dip is most certainly what gneiss mentioned before. Everyone should take note that they give bearings in the problem, should differentiate bearings and azimuth. For the bed thickness problem uh...I mean, gneiss basically explained it, also note that if they inclined the surface it'd throw in a slight curveball (but nothing too terrible). My last point is idk if YUSO wants people putting up those questions, but oh well .

As for binder-making, my partner and I actually have the binder split down the middle topic-wise, but I don't know how much that matters. Tbh, I think what helped us a lot was we didn't use the binder as much this year compared to last year.

Now for the other part about getting the geology...to understand the event and geology you probablyyyy have to understand the representative tasks! Strike and dip to start with involves attitudes, orientations, of different geologic features (like beds of rocks). I'd say the major thing is to just know the "T" symbol with that. The bed thickness problem doesn't really test such an in depth knowledge of strike and dip, a geologic cross section on the other hand might.

For stereonets, I don't see much the issue with the youtube site and the uwgb site (I believe this is linked on the scioly wiki). Both show the process alright, unless people need more help conceptualizing things (the stereonet actually does have a point I've learned!).

Finding flood risk just involves spotting where on a map is closest to a river/valley. If you're in a valley with a river, the river gets some massive overflow from heavy rains, then it's bad news for anyone living there. If you're on high ground away from the river things are better. It's fairly logical...I didn't really love the hazards part to this year since I haven't seen it come up much or if it has it's been really random . But I guess that depends on the writer, so oh well.

...so other questions?