BROOKLYN COLLEGE GEOLOGY DEPARTMENT CORC 1332: Review for Exam 1 Exam 1– Tuesday, 10/16/2012 6:05-7:45 rm 3127N The PowerPoint is to help you focus on

BROOKLYN COLLEGE GEOLOGY DEPARTMENT

CORC 1332: Review for Exam 1

• Exam 1– Tuesday, 10/16/2012 6:05-7:45 rm 3127N

• The PowerPoint is to help you focus on what will be on the exam.

• The exam will consist of approx. 40 questions (multiple choice and T/F)

• You are responsible to bring with you: pencil, calculator, string and ruler *Cell phones cannot be used during exam including as a calculator *

Exam 1 Office hours ….Also posted on website

Michelle Tuesday 10/9/12 12:30-1:30 pmPeter Tuesday 10/9/12 5-6 pmKatya Wednesday 10/10/12 4:30-5:30 pm

*All in room 3114N*

Bring with you specific questions so we can best help you.


Review for Exam 1: Mineral Properties

►KNOW THE DEFINITION OF A MINERAL AND A ROCK

A MINERAL is a naturally occurring, inorganic solid, with a characteristic chemical composition, a highly ordered atomic structure and specific physical properties.

A ROCK, by comparison, is an aggregate of minerals (and other debris such bones or shells) and need not have a specific chemical composition.

http://www.brooklyncollegegeology.com/minerals/mineral_def.html



►Know the difference between Cleavage and Fracture

Cleavage and Fracture are mineral properties that describe the way a mineral breaks when stressed.

Cleavage describes the way a mineral breaks along its plane of weakness.

Fracture: A mineral property where the atomic bonding between atoms in the crystal structure uniform, with bonds of equal strength throughout. When these minerals are stressed they shatter making no two pieces truly the same.

http://www.brooklyncollegegeology.com/minerals/cleave_def.html


Understand what defines a substance as a crystal. Understand what defines a substance as a crystal.

Difference between crystal and crystalline texture and Difference between crystal and crystalline texture and examples of each.examples of each.

http://www.brooklyncollegegeology.com/minerals/crystals_cause.htmlhttp://www.brooklyncollegegeology.com/minerals/crystals_cause.html

http://www.brooklyncollegegeology.com/minerals/crystals_def.htmlhttp://www.brooklyncollegegeology.com/minerals/crystals_def.html



Hardness is a measure of a mineral's resistant to abrasion. This property is easily determined and is used widely for field identification of minerals.

►Know the difference between MOH’S hardness scale and the “simple” STEEL NAIL-FINGERNAIL scale.

http://www.brooklyncollegegeology.com/minerals/hardness_def.html



►KNOW HOW TO CALCULATE THE DENSITY OF A MINERAL.

Density or specific gravity is the ratio of the weight of a substance to the weight of an equal volume of water.

Density = Weight/Volume

1) Begin by recording the weight of the specimen, in this case 155.8 grams.



►HOW TO CALCULATE THE DENSITY OF A MINERAL. Density or specific gravity

2) The amount of water displaced is 20ml = 20cc (920-900)3) Divide 155.8g/20cc = 7.79 g/cc.

So, the density of the mineral is 7.79g/cc.

http://www.brooklyncollegegeology.com/minerals/density_def.html



►KNOW WHAT IS STREAK.

The streak of a mineral is the color it displays in finely powdered form. The streak maybe completely different from the color of the hand specimen. One of the simplest ways of determining the streak of a mineral is to rub a specimen across a piece of unglazed porcelain known as a streak plate.

http://www.brooklyncollegegeology.com/minerals/streak_def.html



►KNOW HOW TO APPLY THESE PROPERTIES◄

HARDNESS

DENSITY

STREAK

COLORYou’ll be asked to identify an unknown mineral using these properties which

will be given to you in the test.

Link to mineral ID charts and self-checking table:

http://www.brooklyncollegegeology.com/minerals/resourceMenu_min.html


Maps

You will be responsible to answer questions similar to those on your map assignment.

This includes:•Finding the gradient•Labeling contours•Determining stream direction


Maps: Determine Direction of Stream Flow

In what general direction is the stream flowing? Ans: From West to East(The legs of the letter V give you the direction of flow)


Maps: Distance Between Two Points

What is the straight line distance between points Q and T in miles?

1) We measure the scale with the ruler and now we know that1.5 cm = 100 miles

Scale bar length = 100 milesContour Interval = 50 feet Elevation of point Q = 583 feet Start Point: Q End Point: R


Maps: Distance Between Two Points

What is the straight line distance between points Q and T in miles?

2) We measure the distance between points Q and T which is 8.5 cm = x miles



Maps: Distance Between 2 Points

Calculations


Maps: Distance Between 2 points

Ans: The distance between points Q and T is 567 miles.


Using the information given what is the elevation of contours ‘d’ and ‘k’?

Scale bar length = 100 mContour Interval = 50 feetElevation of point Q = 583 feet Start Point: Q End Point: R

Maps: Labeling Contours

BROOKLYN COLLEGE Earth & Environmental Sciences

Answer: Contour ‘d’ = 400 ftContour ‘k’ = 650 ft

Maps: Labeling Contours

Scale bar length = 100 mContour Interval = 50 feetElevation of point Q = 583 feet Start Point: Q End Point: R

500

500


500

500

f= 600 fth= 650 ftk= 650 ft

Maps: Gradient of a Steam

1) Begin by measuring the length of the stream. Lay carefully a string along the course of the river.


Scale bar length = 100 miles Contour Interval = 50 feet Elevation of point Q = 583 feet Start Point: Q End Point: R

Gradient refers to the steepness between two points. To calculate the gradient we take the difference in elevation (ED) and divide it by the horizontal distance (HD).

First will determine the horizontal distance of the stream.

What is the average gradient of the stream between points R and T?


2) Measure the string with a ruler, in this case the measurement is 5 4/16 inches

which is equivalent to 5 1/4 in or 5.25 in.

4) Complete the calculations and solve for X (on left). The distance measured by the ruler is 884 miles which refers to the horizontal distance.


3) Measure the scale bar in inches, 100miles = .5938 in*.5938 was derived from measuring the scale bar from a screen shot- your measurements will vary depending on screen resolution.

.5938

.5938

.5938

5.25

5.25

* 5.25



Scale bar length = 100 milesContour Interval = 50 feetElevation of point Q = 583 feet Start Point: Q End Point: R

Next, Determine the difference in elevation measuring the heights of points R and T. Begin by labeling all of the contours using the given information (below) and determine the contour interval of R and T.

Scale bar length = 100 mContour Interval = 50 ftElevation of point Q = 583 ft Start Point: Q End Point: R


5) Find the difference between R and T (R = 500 ft, T = 400 ft)500 ft - 400 ft = 100ft

Difference in elevation is = 100ft

500

500


f= 600 fth= 650 ftk= 650 ft


To Recap: Gradient or steepness between two points is the difference in elevation (ED) divided by the horizontal distance (HD):

To Calculate Gradient:(Using the numbers from the previous slides)

Difference in elevation (ED) = 100 feet

Horizontal distance (HD) = 884 miles

100ft

884miles

= 0.11 feet/mileGradient= ED =

HD

*Gradient is equivalent to slope (m=y/x)*



What is the azimuth direction from the start point towards the end point?

Using the protractor we can determine the azimuth direction to be approximately 9o (“9 degrees”). http://www.brooklyncollegegeology.com/maps/compa.html

Maps: Azimuth Direction

Scale bar length = 100 mContour Interval = 50 feetElevation of point Q = 583 feet Start Point: Q End Point: R500

500


Maps: Distance

one inch = 2.54 cmone foot = 12 inchesone mile = 5280 feet

First, we determine the distance between points B and F on the map in inches with the ruler.

What is the distance between points B and F in miles?

We measure 2 4/16 OR 2.25 inches



What is distance between points B and F in miles:

Next we determine the scale of the map, which we are told 1:60,000 (1 inch = 60,000 inches).

Maps: Distance

Now we can convert the map measurement (2.25 inches) using the scale 1:60,000.

1 in = 60,000 in2.25 in X

X = 135,000 inches


Lastly, we convert 135,000 inches to feetthen to miles.

Maps: Distance


The distance between points B and F in miles is: 2.1 miles


Maps: Distance


The distance on the map from point A to point C is: 1 9/16 in OR 1.5625 in

What is the distance between points A and C in kilometers?


What is the distance between points A and C in kilometers?

Next, Determine how many map units make up 1.5625 inches.

Maps: Distance

1.5625 in = X

1in 60,000 inX = 93,780 inches


Solve for X by cross multiplying:


Maps: Distance

Now we convert 93,780 inches into FEET, then into MILES and finally Miles into KILOMETERS.

The distance between points A and C in kilometers is 2.4kmone foot = 12 inchesone mile = 5280 feetone mile = 1.6 km


Maps: Topographic Features

Describing Topography:Be able to identify topographic features on a geologic map.

http://www.brooklyncollegegeology.com/maps/top_describe_menu.html

Gentle Slope-widely space contours

Hill

Steep Slope: narrow spaced contours

Closed Depression


Maps: Topography

Match the following contours with the appropriate profiles:


Maps: Topography

Match the following contours with the appropriate profiles:

1 B

2 E

3 D

4 C

5 F

6 A

BROOKLYN COLLEGE GEOLOGY BROOKLYN COLLEGE GEOLOGY DEPARTMENTDEPARTMENT

Review for Exam 1Geologic Map

Examine the geologic map shown above. The rectangles represent outcrops of bedrock. Assume that each of the

individual formations maintains a more or less constant thickness throughout the region.

BROOKLYN COLLEGE GEOLOGY BROOKLYN COLLEGE GEOLOGY DEPARTMENTDEPARTMENT

At drill hole E we hit Formation 1

At drill hole A we hit Formation 2

At drill hole D we hit what Formation??

Review for Exam 1Geologic Map

**Please keep in mind you must be consistent with the thicknesses of the beds as you draw your line connecting Formations.

http://www.brooklyncollegegeology.com/maps/geologic_maps_menu2.html

What is an outcrop?

What is bedrock?

What are the differences between the two?

►Bedrock is a layer of undisturbed rock usually located beneath a surface layer of soil or other material.

►A surface exposure of bedrock is called an outcrop.

http://www.brooklyncollegegeology.com/maps/nyc_mins2/bedrock_rollover.html


Locations w/in the NYC Metropolitan Area

Be able to identify all areas on the map. Could you:

--Identify each borough, body of water and New Jersey?

--Name the borough located furthest North, South, East West?

http://www.brooklyncollegegeology.com/maps/geog_nyc_menu2.html


Longitude and Latitude

http://www.brooklyncollegegeology.com/maps/latlong_menu.html

Any point on a line of latitude is its position North or South of the equator.

For example the Latitude of J is 5° 59’ 45” North (green arrow)

Any point on a line of longitude is its position East or West of the Prime Meridian.

For Example the Longitude of J is 71o 00’ 00” West (pink arrow)



Maps: Longitude and Latitude

Answer:Latitude (Horizontal) 5o 59’ 45” North

Longitude (Vertical) 71o 00’ 00” West

What is the latitude and longitude at point J?

Determining the latitude and longitude of a point

http://www.brooklyncollegegeology.com/maps/lat_long.html


Maps: Longitude and Latitude

What is the latitude and longitude at point H?

For the latitude: (pink arrows)We see that point H is between 5o 59’ 45” and 6o 00’ 00” so we have 15” in between. We take half of 15” which is about 8” and add those 8” to 45” to get a latitude of 5o 59’ 53”.

For the longitude: (blue arrows)We see that point H lies between 71o 00’ 00” and 71o 00’ 45” so we have 45” in between. Take half of 45” which is about 23” so we add those seconds to 00” to get a longitude 71o 00’ 23”.

Documents

BROOKLYN COLLEGE GEOLOGY DEPARTMENT CORC 1332: Review for Exam 1 Exam 1– Tuesday, 10/16/2012 6:05-7:45 rm 3127N The PowerPoint is to help you focus on