1 - Sedimentary cycles

who believes that all rocks on the surface of the ocean were precipitated from a global ocean?

abraham werner

what is the difference between time stratigraphic (time-rock) and chronological (time) units

time stratigraphic units = units of rock deposited over a particular period of geological time

Chronological units = periods of geological time

closer to the fraser river, the sediment is _____ (fine/coarse) and closer to the ocean the sediment is _____ (fine/coarse)

coarse at river, finer closer to sea

at the fraser river delta, the sediment in front of the delta is ___ (soft/hard)

soft, with heavier on top = cool sedimentary structures

at what depth and temperature does diagenesis occur?

~10km depth at ~180 C

at what depth and temperature does contact metamorphism occur?

~10km depth and from 180-780 C

at what depth and temperature does regional metamorphism occur?

5km to 40 km depth at 75-700 C

at what depth and temperature does melting occur?

0-40km depth but at like 700 C

clastic rocks can be split into 2 groups:

volcaniclastic and clastic

non clastic rocks can be split into 2 groups:

evaporites and “others”

types of volcaniclastic rocks

tuffs, ignimbrites

types of clastic rocks

mudrocks, sandstones, conglomerates

what type of rock can be both clastic AND non-clastic

carbonates, such as limestones as they can have lithic fragments as well as biogenic materials and chemical precipitates

in the non-clastic category, what does “others” consist of

coal, ironstones, phosphates, siliceous

4 components we can look at when classifying rocks

mineral grains, lithic fragments, biogenic materials, and chemical precipitates

which type of rocks do mineral grains play an important role?

volcaniclastic and clastics

which type of rocks do lithic fragments play an important role?

volcaniclastics, carbonates, volcaniclastic

which type of rocks do biogenic materials play an important role?

carbonates, “others”, clastics

which type of rocks do chemical precipitates play an important role?

“others”, evaporites, carbonates

why are sedimentary rocks important

oil/gas/ore deposites

building materials

Earths tape recorder

how much of the earths surface do sedimentary rocks take up

like 75% !!!

define sedimentology

the study of sedimentation

define stratigraphy

science of rock strata

define sedimentary petroGRAPHY

description and classification of sedimentary rocks

define sedimentary petroLOGY

the study of the composition and origin of sedimentary rocks

how many white old guys contributed to historical geological concepts

7

what did leonardi da vinci do

recognized fossils were once living organisms

what did james ussher do

said earth was created 4000 years before birth of christ, used the bible to interpret

what did nicholas steno do

principle of superposition, original horizontality

what did abraham wener do

thought that all rocks precipitated from a global primitive ocean (from a biblical flood), and thought igneous rocks were “primordial precipitate”

1. primitive

2. transition

3. Secondary

4. Alluvial/tertiary

5. Volcanic

was abraham werner a neptunist of plutonist

neptunist

was james hutton a neptunist or plutonist

plutonist

who is the father of geology

james hutton

what did james hutton do

viewed world as cyclical (erosion/deposition, rock cycle, etc), also that igneous rocks crystallized from melts (uniformitarianism)

what is uniformitarianism

processes that operate today operated in the past (rock cycle, etc), earth is dominated by slow processes

ideas that plutonists use to confirm theory

cross cutting relationships, unconformities

what did charles lyell do

popularized uniformitarianism

what did william smith do

geological maps, law of faunal succession, fossil correlation

neptunists follow the idea of…. (catastrophism/uniformitarianism)

catastrophism

plutonists follow the idea of…. (catastrophism/uniformitarianism)

uniformitarianism

what is catastrophism

earth is dominated by violent events, related to bible, earth formed due to a bunch of catastrophes

where are the best preserved rocks found?

in environments where theyre unhappy or where theyre unexpected to be

in reality, is uniformitarianism or catastrophism more realistic

both. uniformitarianism with a smattering of catastrophes

what is an isopach map

thickness map

what is an isolith map

an isopach map of a specific lithology

what is a structure map

depth below sea level to a unit

a time-stratigraphic log uses ____ to correlate

fossils

a stratigraphic log uses _____ to correlate

rocks

a structural stratigraphic log uses ____ to correlate

rocks relative to sea level

should we vertically exaggerate column cross sections?

yes

what is the datum

represents sea level

does the datum always have to be 0?

no, it can be anything.

ex) datum = 5000

must add/subtract 5000 relative to it ya know

what do we use as the datum in stratigraphic cross sections

a distinct lithological boundary

what do you use for the datum for a time stratigraphic cross section

use the occurrence of a fossil

time is the datum

do time lines run parallel to lithological boundaries? and what does that imply?

no, therefore formations are not the same age everywhere