KOCHEL MILLERRITTER

INTRODUCTION

What is Process Geomorphology?

I. Overview

A. Geomorphology (def): the study of landforms.

I. Overview

A. Geomorphology (def): the study of landforms.

Descriptive → Quantitative

I. Overview

A. Geomorphology (def): the study of landforms.

Descriptive → Quantitative

“an interdisciplinary science”

“the trade of geomorphology”

I. Overview

B. Process Geomorphology:

I. Overview

B. Process Geomorphology:

1. concept of process….

I. Overview

B. Process Geomorphology:

1. concept of process….the action involved when a force induces a change (either chemical or physical) in the materials or forms at the earth’s surface.

I. Overview

B. Process Geomorphology:1. concept of process….the action involved when a force induces a change (either chemical or physical) in the materials or forms at the earth’s surface.2. Loose definition: ”The study of landforms and the methods by which the landforms were(are) created”

II. The Basics of Process Geomorphology

II. The Basics of Process Geomorphology

A. A delicate balance or equilibrium exists between landforms and process.

1. Geomorphic Systems

II. The Basics of Process Geomorphology

A. A delicate balance or equilibrium exists between landforms and process. 1. Geomorphic Systems

The balance between form and process is best demonstrated by considering both factors as systems or component of systems. A system is a collection of related components

II. The Basics of Process Geomorphology

A. A delicate balance or equilibrium exists between landforms and process.

1. Equilibrium?????!!!!

1. Equilibrium?????!!!!

Implies that landforms and processes exist in some type of unchanging condition (a balance of forces)

II. The Basics of Process Geomorphology

A. A delicate balance or equilibrium exists between landforms and process.

1. G.K. Gilbert – “dynamic

adjustment”

Landforms reflect the interaction between the dominantprocess and the local geology

II. The Basics of Process Geomorphology A. A delicate balance or equilibrium exists

between landforms and process.

2. William Morris Davis

“cycles of erosion”

II. The Basics of Process Geomorphology A. A delicate balance or equilibrium exists

between landforms and process.

3. John Hack

“dynamic equilibrium”

II. The Basics of Process Geomorphology

A. A delicate balance or equilibrium exists between landforms and process.

2. Defining Equilibrium and Time Scales

Schumm (1977)

Valley Point FarmIvy, VA

low

high

Time (years)

Fig. 1.3

From Schumm (1977)

low

high

Time (years)

Fig. 1.3

From Schumm (1977)

low

highFig. 1.3

From Schumm (1977)

II. The Basics of Process Geomorphology B. The perceived balance between process

and form is created by the interaction of energy, force, and resistance.

II. The Basics of Process Geomorphology B. The perceived balance between process

and form is created by the interaction of energy, force, and resistance.

Process: (def) The action involved when a force induces a change in the materials or landforms at the Earth’s surface. OR

II. The Basics of Process Geomorphology B. The perceived balance between process

and form is created by the interaction of energy, force, and resistance.

Process: (def) The action involved when a force induces a change in the materials or landforms at the Earth’s surface. OR

The method by which one thing may be produced from something else.

Process are either:

Exogenic: at or near earth’s surface

Endogenic: energy initiating the action is inside the earth

Force:

Ingredients:

Force:

Ingredients:

Force F = m * a

weight = mass * gravity

A measure of force is weight (pounds, newtons)

Force:Ingredients:Force F = m a

weight = mass * gravity

A measure of force is weight (pounds, newtons)

Force ~ energy, where energy is defined as the capacity to do work.

Force:Ingredients:*Force F = m a

weight = mass * gravity

A measure of force is weight (pounds, newtons)

Force ~ energy, where energy is defined as the capacity to do work.

Energy (or work) = force*distance = mass *gravity *ht F * d m * a *ht

A measurement of energy is Joules

Modification of landforms results from the application of energy.

Landforms represent the interaction between driving forces and resistance.

 Driving Forces: Resistance Forces:

Modification of landforms results from the application of energy.

Landforms represent the interaction between driving forces and resistance.

 Driving Forces: Climate, Gravity, Forces generated inside the earthResistance: Provided by the geologic framework

The link between these two components here is PROCESS

II. The Basics of Process Geomorphology C. Changes in the balance between driving

and resisting forces may destabilize the system. The system may cross a threshold, and may initiate a new pattern of equilibrium.

II. The Basics of Process Geomorphology C. Changes in the balance between driving

and resisting forces may destabilize the system. The system may cross a threshold, and may initiate a new pattern of equilibrium.

1. Thresholds

Changes in the geomorphic system when the limits of equilibrium are exceeded

II. The Basics of Process Geomorphology C. Changes in the balance between driving

and resisting forces may destabilize the system. The system may cross a threshold, and may initiate a new pattern of equilibrium.

1. Thresholds

Changes in the geomorphic system when the limits of equilibrium are exceeded

‘BEFORE’ ‘AFTER’

1. Thresholds

Changes in the geomorphic system when the limits of equilibrium are exceeded

a. Extrinsic Thresholds: caused by external controlling factors

b. Intrinsic Threshold: usually caused by internal factors.

Geomorphic Thresholds: refers to the stability of a landform itself.

II. The Basics of Process Geomorphology C. Changes in the balance between driving

and resisting forces may destabilize the system. The system may cross a threshold, and may initiate a new pattern of equilibrium.

2. Complex Response (concept)

a. " landforms behave differently spatially at the same time from a disturbance."

II. The Basics of Process Geomorphology D. Various processes are linked in such a

way that the effect of one process may initiate the action of another.

Process linkage: “Domino Effect”

II. The Basics of Process Geomorphology E. Geomorphic analysis can be made over a

variety of time intervals. The interval of time chosen will have a bearing on conclusions made regarding the relationship between process and form