Stratigraphy

Question 1

The study of temporal and spatial relationships between bodies of sedimentary rocks.

Answer 1

Stratigraphy

Question 2

What is the goal of stratigraphic analysis?

Answer 2

To establish the temporal sequence of
sedimentary rocks in the area under investigation.

Question 3

Principles of Stratigraphy

Answer 3

Law of Superposition
Law of Original Horizontality
Lateral Continuity
Cross-Cutting Relationships
Inclusion
Unconformity
Law of Faunal Succession

Question 4

The oldest layer is at the base and that the layers are progressively younger with ascending order in the sequence.

Answer 4

Law of Superposition

Question 5

All rock layers are originally laid down (deposited) horizontally and can later be deformed.

Answer 5

Law of Original Horizontality

Question 6

All rock layers are laterally continuous and may be broken up or displaced by later events.

Answer 6

Lateral Continuity

Question 7

Younger rocks cut across older rocks.

Answer 7

Cross-Cutting Relationships

Question 8

Any rock fragments that are included in rock must be older than the rock in which they are included.

Answer 8

Inclusions

Question 9

Represents a long period during which deposition ceased, erosion removed previously formed rocks, and then deposition resumed. In each case, uplift and erosion are followed by subsidence and renewed sedimentation.

Answer 9

Unconformity

Question 10

States that a species appears, exists for a time, and then goes extinct. Time periods are often recognized by the type of fossils you see in them.

Answer 10

Law of Faunal Succession

Question 11

Determining a sequence of events occurred in the history of earth using the evidence of organic evolution in the sedimentary rocks accumulated through geologic time.

Answer 11

Dating

Question 12

It is when rocks and events are put in correct order of sequence relative to one another.

Answer 12

Relative Dating

Question 13

The age of rocks units are determined precisely in years using the rate of decay of naturally occurring radioactive elements.

Answer 13

Absolute Dating

Question 14

Usually a product of interpretation of other stratigraphic analysis of the basin.

Answer 14

Chronostratigraphy

Question 15

Its ultimate aim is to arrange the sequence of deposition and the time of deposition of all rocks within a geological region.

Answer 15

Chronostratigraphy

Question 16

Uses fossils to establish relative ages of rock and correlative successions of sedimentary rocks within and between depositional basins.

Answer 16

Biostratigraphy

Question 17

Fossils used in petroleum industry?

Answer 17

Microfossils
Nanofossils
Palynomorphs

Question 18

An interval of geologic strata characterized by certain fossil taxa.

Answer 18

Biozone

Question 19

Relies on the correlation of rocks of the same characteristics. Most maligned stratigraphic method and also the oldest of them all.

Answer 19

Lithostratigraphy

Question 20

The study of seismic data for the purpose of extracting stratigraphic information.

Answer 20

Seismic/Tectonic Stratigraphy

Question 21

Generated by the accumulation of sediments in a basin wherein major changes brought about by the tectonics in the area affects the gross structure of sediment package.

Answer 21

Seismic/Tectonic Stratigraphy

Question 22

What are the different margins identified by tectonic stratigraphy?

Answer 22

Reef Basins
Passive Margin
Foreland Basins
Wrench Systems

Question 23

Packages of sediment deposited before, during, and after the active rift phase can often be clearly identified on regional seismic lines.

Answer 23

Reef Basins

Question 24

A development of a successful rift. It can develop over a substantial period of time, thus, the megasequence can be enormously thick

Answer 24

Passive Margins

Question 25

Forms contemporaneously with the flexuring of the lithosphere caused by thrust loading. The shape is commonly elongate parallel to the thrust belt.

Answer 25

Foreland Basins

Question 26

Megasequences developed during strike-slip are commonly of small aerial extent. The sequences may be symmetric, as in transtensional systems, or asymmetric, as in transpressional systems. The overall geometry of the megasequences is commonly like that of their syn-rift and foreland counterparts in extensional and compressional basins.

Answer 26

Wrech Systems

Question 27

Involves the geochemical classification and correlation of sedimentary strata by using major and trace element geochemistry, which is highly helpful when applied to sequence with poor biostratigraphic control.

Answer 27

Chemostratigraphy

Question 28

A geophysical correlation technique used to date sedimentary and volcanic sequences. The method works by collecting oriented samples at measured intervals throughout the section and analyzing the magnetic polarity of each sample.

Answer 28

Magnetostratigraphy

Question 29

A branch of sedimentary stratigraphy that deals with the order or sequence in which depositionally related stratal successions (time-rock) units were laid down in the available space or accommodation. It is developed from seismic stratigraphy.

Answer 29

Sequence Stratigraphy

Question 30

A geologic event in which sea level rises relative to the land and the shoreline moves toward higher ground, resulting in flooding. It can be caused by either the land sinking or the ocean basin filling with water.

Answer 30

Transgression

Question 31

With a rise in sea level, we see a landward shift of facies zones and the stratigraphic section reveals the texture is fine upward.

Answer 31

Transgression

Question 32

A geological process occurring when areas of submerged seafloor are exposed above the sea level. A marine regression when sea level is falling.

Answer 32

Regression

Question 33

With a fall in sea level, we see a seaward shift of facies zones and the stratigraphic section reveals that texture coarsens upward

Answer 33

Regression