Chapters 13-21 Flashcards
(42 cards)
What are the various provinces across an ocean basin?
In order from coast:
Continental Margin (Continental shelf, continental slope), Deep-ocean Basin, Oceanic Ridge system
How do the cross-sections of passive and active oceanic boundaries differ?
Passive boundaries are simply a transition between ocean and continent. Active boundaries include subduction zones, usually involving a deep-ocean trench and a volcanic arc.
What is orogenesis, and what are the different types of it?
Orogenesis is the process of mountain building, and the types are island arc, Andean-type, Alpine-type, and Cordillera-type
What is island arc orogenesis?
The building of mountains as a belt of volcanoes resulting from steady subduction of oceanic lithosphere
What is Andean-type orogenesis?
The building of mountains that starts with a passive continental margin, which eventually activates, generating a subduction zone and a volcanic mountain arc
What is Alpine-type orogenesis?
Mountain building as the result of two continents colliding
What is Cordillera-type orogenesis?
Mountain building as the result of an island arc being shoved onto land; associated with the Pacific ocean
What is a craton?
The old, stable layer of continental lithosphere
What is a shield?
The very oldest part of a continent, usually the core around which the rest of the continent formed
What are fault-block mountains?
Mountains formed by the faulting of rocks, some of which is downthrust to cause the mountainous remainder’s height
What is runoff?
Water which falls as rain but is not absorbed by the ground
What is stream discharge?
The volume of water flowing past a certain point in a given unit of time, measured in m^3/s
What affects stream discharge? (4)
The slope, shape, size, and roughness of the channel
What is the bed load and how is it moved?
The sediments carried by the river along the bottom; move by rolling or jumping
What is the suspended load?
The sediments carried by the stream which are light enough to be fully kept from sinking
What is the dissolved load?
The sediments carried by a stream as dissolved ions
What is the zone of saturation?
The zone of an aquifer in which the majority of pores are filled with water
What is the zone of unsaturation?
The area above an aquifer which in which there are pores, but the majority of them are unfilled with water
What is the water table?
The plane which divides the saturated and unsaturated zones of an aquifer
What is the difference between porosity and permeability?
Porosity is the space between grains in sediment or rock. Permeability is the ability of water to flow between the grains of sediment or rock.
What is Darcy’s Law?
Q=(K(h1-h2)/d)X, where Q is discharge, K is hydraulic conductivity, (h1-h2)/d is the hydraulic gradient, and X is area over which discharge is measured
What are the types of glacier?
Ice sheets, which cover huge areas over continents, and valley glaciers, which form in the valleys of high-altitude mountains
What is Milankovitch theory?
The theory that the glacial cycles are caused by astrophysics, specifically earth’s eccentricity, obliquity, and precession
What is eccentricity?
Variations in the shape of Earth’s orbit
