1.2 FAULTS AND FOLDS Flashcards
It is a branch of geology concerned with the study of rock layers (strata) and layering (stratification). It is primarily used in the study of sedimentary and layered volcanic rocks.
Stratigraphy
He presented four basic principles that govern the way that sedimentary rocks are deposited and layered.
Nicholas Steno
These are the four basic principles that govern the way that sedimentary rocks are deposited and layered.
Steno’s Principles of Stratigraphy
When did Nicholas Steno present his four basic principles?
17th Century
STENO’S PRINCIPLES OF STRATIGRAPHY
This law states that younger layers of rock sit atop older layers.
Law of Superposition
STENO’S PRINCIPLES OF STRATIGRAPHY
This law states that layers of sedimentary rock are originally deposited flat.
Law of Original Horizontality
STENO’S PRINCIPLES OF STRATIGRAPHY
This law states that rock layers A and B must be older than the intrusion (C) that disturbs them.
Law of Cross-Cutting Relationships
The Law of Cross-Cutting Relationships is later reinforced by who?
James Hutton
STENO’S PRINCIPLES OF STRATIGRAPHY
This law states that layers of rock are continuous until they encounter other solid bodies that block their deposition or until they are acted upon by agents that appeared after deposition took place.
Law of Lateral Continuity
These are surfaces within rock sequences that represent gaps in the geologic record, due to periods of erosion or non-deposition, meaning some rock layers are missing, representing a “break” in time.
Unconformities
TYPES OF UNCONFORMITIES
These are between parallel layers of sedimentary rock. The rock layers on both sides of this unconformity are generally horizontal and have similar orientations.
Disconformity
TYPES OF UNCONFORMITIES
These are horizontally deposited sedimentary rock layers that are uplifted, tilted, or folded, eroded, and then covered by new, horizontally deposited layers
Angular unconformity
TYPES OF UNCONFORMITIES
An unconformity between younger sedimentary rocks and older igneous or metamorphic rocks.
Nonconformity