History of Geomorphology Flashcards
what is geomorphology
the study of earth landforms
describe the current working paradigm
systems theory and dynamic equilibrium
what is involved in the study of geomorphology
- mineralogy
- structures
- tectonics
- stratigraphy
- chemistry
- physics
- meteorology and climate
why bother studying geomorphology
allows understanding towards topics like:
- climate change
- past tectonic activity
- engineering problems
- hazard assessment
- stratigraphy
how does geomorphology allow understanding of climate change
relating to how systems respond differently to the same conditions
how does geomorphology allow understanding of past tectonic activity
relating to distinct stratigraphic and landform features
how does geomorphology allow understanding of engineering problems
the construction of structures depends on understanding potentially destructive events
how does geomorphology allow understanding of hazard assessments
allows the mapping of areas with high risk of disasters (map of where to build structures and where not to)
how does geomorphology allow understanding of stratigraphy
relates to reading the stratigraphic record of the past which is a narrative of geologic past
what are some agents of change in landscapes
- gravity (ex. landslides)
- rivers and oceans
- glaciers and ice
- wind (transporting sediments)
- humans
how are humans a huge agent of change in landscapes
- construction (changing habitats and ecosystems - building dams, steepening slopes…)
- damaging the biosphere
(removing biodiversity by removing plants) - recreational activities (damaging the landscape - hiking, camping)
- water usage (lowering water tables which increase erosion and sink holes)
- climate change
(pollution, upping temperatures)
how was earth viewed back in the 17th and early 18th century
as relatively static (not changing)
how were changes in landscape explained in the 17th century/early 18th
according to catastrophism
what is catastrophism
Belief that the surface of the Earth was shaped by a series of infrequent high-magnitude events that were separated by long periods of time
what was catastrophism often related to
Biblical events (Noah’s flood for example)
Uniformitarianism
Idea that changes to earth’s surface in the geologic past were caused by the same processes, operating at the same rates, that are slowly changing earth’s surface today
what were the two opposing concepts regarding changes to earth’s surface
Catastrophism and Uniformitarianism
when was Uniformitarianism introduced
late 18th and 19th century
works of who introduced the concept of Uniformitarianism
Hutton, Playfair, Lyell
based on Catastrophism, how old was the world estimated to be
about 6000 years old
how did Uniformitarianism update the age of the earth
by claiming the earth was much older than 6000 years, about 1 million instead
what was proposed about earth’s surface in the late 19th century
that landforms reflect an adjustment between geomorphic processes and geology (looking at the processes that form the landscapes)
recap the development of geomorphology through the ages
- starts in the 17th and early 18th century with the idea of catastrophism and how earth’s surface was viewed as static
- later in the late 18th and 19th century Hutton, Lyell and Playfair introduced the topic of Uniformitarianism
- the late 19th century saw Gilbert proposing the idea that landforms reflect the adjustment between geomorphic process and geology
- geomorphologists were than lured by the Davisian model of landform development based on principles of evolution
how was evolution seen in geomorphology
principle that landscapes evolved through time which allowed for the changes seen today
when evolution first became a part of geomorphologic formations, what was wrong with the proposal
evolution on landscapes was seen as unilateral while in reality evolution is almost cyclic
how can stages of evolution in a landscape be determined
by examining the characteristics of the landscape
how did the evolutionary view of landscape formation shift the age of the earth
pushed it way back (further than Uniformitarianism) to support the idea of gradual evolution of landscapes
what is a critical factor in determining what the landscapes look like
TIME
who originally proposed equilibrium
G K Gilbert
who championed the evolutionary development of landscapes
W M Davis
was the original claim that landscapes are static correct
NO - landscapes are in dynamic equilibrium
how is a landscape in dynamic equilibrium
the landscape is in a a constant shifting/battle to hold a state of balance between driving and resisting forces