ES Notes-Geologic Time to Hydrologic Cycle - General Earth...

General Earth Science Notes
A. Geologic Time
a. Relative time - what the sequence of events are that produced the rock
i. Law or original horizontality is for sedimentary rocks
ii. Principle of cross-cutting relationships
1. Faults
2. Igneous intrusions - dikes, sills
iii. Law of Superposition is for sedimentary rocks
1. Stuff on top is youngest
iv. Principle
b. Geologic time scale
i. Chart used to show changes in time
ii. Eras
1. Cenozoic
2. Mesozoic
3. Paleozoic
4. Precambrian
iii. Periods - what is commonly used to describe the ages of rocks; p. 328 &
337
iv. Epoch - holocene Epoch - now
A. Hydrologic Cycle
a. Evaporation
b. Precipitation
c. Infiltration
d. Runoff
e. Transpiration
B. Drainage patterns
a. Dendritic Drainage
b. Trellis       "     "
c. Radial
d. Rectangular
C. Discharge and Velocity
a. Discharge
i. Q=A*v
1. A=cross sectional area
v=velocity (speed at which water is moving)
ii. Increases
1. Larger stream channel
2. Higher velocity
D. Stream flow
a. Changes in stream flow down stream

i. Youthful streams have steep gradient
ii. Mature streams have more gentle gradient
E. Groundwater
a. Properties of rock and sediment
i. Porosity
1.