Chapter 9: Endogenic Processes

Cinders

(2-4 mm)

Lapilli

(4-64 mm)

Blocks

(>64mm)

Lava flows; Shield volcanoes; Cinder cones Composite cones; Plug domes; Calderas

6 major kinds of volcanic landforms

Graben

Each block that slid downward between two normal faults, or that remained in place while blocks on either side slid upward along the faults is called _____

Within; originating

Endo:______; genic:_______

Endogenic processes

Geomorphic processes that originate within earth, tend to increase the amount of surface relief

Tekton

Greek: __________ , carpenter, builder

Charles F. Richter (1935)

He developed a numeric scale of earthquake magnitude to express the size of earthquakes

Nevados Ojos del Salado

Highest volcano, an andesitic composite cone that reaches an elevation of 6887 m

European Alps

Highly complex folding created the ________, where folds are overturned, sheared off, and piled on top of one another

Sill

Horizontal sheet of intrusive igneous rock

Mountain ranges; Basins

Horsts form __________ Grabens form _______

Tectonic forces

Move the lithospheric plates, also causd bending, warping, folding and fracturing of Earth's crust at continental, regional and even local scales

Landforming tectonic processes

Movements of parts of the crust and upper mantle, and igneous processes

Appalachian Mountain system

Much of the ______ is an example of folding on a large scale

Laccolith

Mushroom-shaped intrusion that develops where molten magma pushes its way between preexisting horizontal layers of other rock

Millimeters; Centimeters

Natural landforming processes proceed at a wide variety of rates usually expressed in ________ or ________ of change per year, century or millenium

Columnar-jointed basalt flows

Network of vertical fractures that break the rock into numerous hexagonal columns creates ________

Escarpment

Often shortened to scarp, is a steep cliff, which may be tall of short

Landforms

One of the most appealing and impressive elements of Earth's surface

Flowing water; Wind; Moving ice; waves People

The most common geomorphic agents are ____, _____,______ and _____ but organisms including ________ also accomplish some erosion, transportation and deposition of weathered pieces of Earth material.

Rock structure

The nature, orientation, inclination, and arrangement of affected rock layers

Fold limbs

The rock layers that form the flanks of anticlinal crests and synclinal troughs

Dike

The solidified magma in this case has a wall-like shape and is known as ____

Angle of repose

The steepest angle that a pile of loose material can maintain without rocks sliding or rolling downslope

Focus; 700 km

The subsurface location where rock displacement and the resulting earthquake originate is the earthquake ______, which may be located anywhere from near the surface to a depth of _______

Endogenic processes, exogenic processes, relative strength of resistance of different rock types

The topographic variation on Earth's surface results from the interaction of 3 major factors: _____

aa

This causes the thick layer od hardened crust to break up into sharp-edged, jagged blocks, making a surface known as ____

Geomorphology

Understanding landforms and landscapes - how they originate, why they vary- is the primary goal of __________

Anticlines

Upfolds

Thrust fault

Where compression pushes a mass of rock along a low-angle fault so that it overrides rocks on the other side of the fault, the fracture surface is called ____

Plug dome

Where extremely viscous silica-rich magma pushes up into the vent of a volcanic cone but does not flow farther, it forms ____

Tectonic and igneous processes

______ constitute the endogenic geomorphic processes.

Geoscientists

______ use strike and dip to describe the orientation of tilted rock layers.

0 degree dip

_______ = horizontal

Tectonic and igneous processes

________ and __________ build extensive mountain systems and a great variety of other landforms.

Landforms

________ represent the interplay of one set of processes that elevate, depress, or disrupt Earth's surface.....

Geomorphologists

________ seek explanations for the origin, shape, and spatial distribution of terrain features of all kinds and for the processes that modify and destroy them.

Death Valley, Californa

_________ is a classic example of the downtilted side of a tilted fault block

Exogenic processes

_________ work to decrease relief

Folding

a bending or crumpling of rock layers

Geomorphology

a major subfield of physical geography devoted to the scientific study of landforms

Andesite

a volcanic rock intermediate in silica content and explosiveness between basalt and rhyolite

Vent

almost poplike conduit for the eruption

Magmas

contain large amounts of gases that remain dissolved when under high pressure at great depths

Stress

force per unit area

Felsic magmas

have a higher viscosity than mafic magmas(contain less silica)

Explosive eruptions

violently blast pieces of molten and solid rock into the air

Reverse fault

steep, high-angle fault resulting from compressional force

Earthquake intensity

the damage caused by an eartquake and the degree of its impact on people and their property

Strike-slip fault; Lateral fault

the direction of slippage is parallel to the surface trace, or strike, of the fault; thus it is called a ________, because of the horizontal motion __________

modified Mercalli scale

uses categories numbered from I to XII to describe the effects of an earthquake on humans and the spatial variation of those impacts

Fault scarp

A cliff that results from movement along a fault is specifically a _______ Are commonly visible in the landscape along normal fault zones

Horst

A fault block that moved relatively upward between two normal faults

Relief

A fundamental characteristic of all landforms and landscapes

Caldera

A large depression

Geomorphic agent

A medium that picks up, moves and eventually lays down pieces of broken rock matter.

Pahoehoe

A ropy surface form

Volcanic neck

A tall rock spire made of the now-exposed,formerly subsurface pipe

10; 32

Any whole number increase in earthquake magnitude represents a ___ times increase in amplitude on the seismograph trace, but the actual energy released is about ____ times greater

Batholiths

Are complex masses of solified magma, usually granite

Rift valleys

Are long but relatively narrow zones of crust down dropped between normal faults

Volcanoes

Are mountains or hills that form by volcanism

Tectonism

Areas of the crust can be uplifted or down dropped by ___________

Recumbent folds

Asymmetrically folded rocks may become overturned and perhaps so compressed that the fold lies horizontally, these are known as ______

Ductile

Bendable

Igneous intrusions or plutons

Bodies of magma that exist beneath the surface of earth or masses of intrusive igneous rock that cooled and solidified beneath the surface are ______

Brittle

Breakable

Stratovolcanoes

Composite cones are also known as _______

Landforms

Contribute to the beauty and diversity of Earth's environments

Fissures

Deep fractures in the crust

Fault blocks

Discrete blocks

Synclines

Downfolds

Seismic waves

Energy that moves through Earth

External

Exo: _____

Weathering erosion; transportation;deposition

Exogenic process consist of various means of rock breakdown, collectively termed _______, and the removal, movement and relocation of those weathered rock produces in the continuum of processes known as __________, ________ and _________.

Pyroclastic flows

Fast-moving density currents of airborne volcanic ash, hot gases, and steam that fall downslope

Dip-slip faults

Faults with this kind of movement, up or down along the dip of the fault plane extending into Earth, are known as ___

Pyroclastic materials

Fire fragments. Also reffered to as tephra

Dip

The inclination of the rock layer, _____, is always measured at right angles to the strike and in degrees of angle from the horizontal

Epicenter

Is the point on Earth's surface that lies directly above the focus, and it is where the strongest shock is normally felt

Landforms

Landscapes consist of rugged mountains, gently sloping plains, rolling hills and valleys, or elevated plateaus cut by steep canyons. These are just a few examples of the types of surface terrain features, reffered to as ____________.

Volcanic bombs

Large spindle-shaped clasts that solidified while flying through the air

Ignis

Latin:________, fire

Lava flows

Layers of erupted rock matter that poured or oozed over the landscape when they were molten

Volcanic ash

Like tiny silvers of glass

earthquake safe

Probably no area on Earth can be called "_____"

basaltic plateaus

Relatively flat-topped, but elevated tablelands known as _____

Composite cone

Results when formative eruptions are sometimes effusive and sometimes explosive

Volcanic ash

Sand-sized or smaller (<2mm)

(1) the size of the event as a physical earth process (2) the degree of its impact on humans

Scientists express the severity of an earthquake in 2 distinct ways:

Seismographs

Sensitive instruments that measure ground shaking

Overthrust

Shallow displacement

Cinder cones

Smallest type of volcano, typically only a couple of hundred meters high, consist largely of gravel-sized pyroclastics

Joints

Solidified lava flows tend to have many fractures known as ____

Colorado, Wyoming, Montana, Canadian Rockies

Spectacular folds exist in the Rocky Mountains of _____, _______, and _______ and in the ______

Cinder cone

Steep straight sides and a crater at the top of the hill

Off the coast of Chile, 9.5, 1960

Strongest earthquake, magnitude and when

Compressional tectonic forces Tensional tectonic forces Shearing tectonic forces

Tectonic forces are divided into 3 principal types that differ in the direction of the applied forces. These are ____

Compressional tectonic forces

Tectonic forces that push two areas of crustal rocks together, tend to shorten and thicken rocks

Hawaii

Terms pahoehoe and aa both originated in ______, where effusive eruptions of basalt are common

Relief

The difference in elevation between the highest and lowest points within a specified area or on a particular surface feature

Left lateral; right lateral

The direction of motion along a strike slip fault is described as ______ or ________

Fault

The fracture along which movement has occurred is a ___

Lithospheric plate boundaries

The greatest tectonic forces, most dangerous earthquake zones, and largest mountain ranges lie along ______

Earthquakes

are ground motions of Earth caused when accumulating tectonic stress is relieved by the sudden displacement of rocks along a fault

Sedimentary rocks

are particularly useful for identifying tectonic deformation

Effusive erruptions

molten rock pours less violently onto the surface as flowing streams of lava

Strike

is the compass direction of the line that forms at the intersection of a tilted rock layer and a horizontal plane

Faulting

is the slippage or displacement of rocks along a fracture surface

Silica (SiOsub2)

primary material component that contributes to a higher viscosity in molten rock

Tensional tectonic forces

pull in opposite directions in a way that stretches and thins the impacted part of the crust Commonly cause the crust to break into discrete blocks

Plutonism

refers to igneous processes that occur below Earth's surface, including the cooling of magma to form intrusive igneous rocks and rock masses

Volcanism

refers to the extrusion of rock matter from earth's subsurface to the exterior and the creation of surface terrain features as a result

Viscosity

resistance to flowing

Shield volcano

shape of a large mountain, which resembles a giant knight's shield resting on earth's surface, eruptions are not very explosive

Shearing tectonic forces

slide parts of Earth's crust past each other