Understanding basic geology is a must for understanding how contaminants travel through the subsurface environment.

This letter is the first in our Geology 101 Series illustrating geology to the novice in terms that even the expert can understand.

For more information please refer to the newsletter section in our web site www.amiadini.com.

Geology for the Uninitiated

Fold, in geology, means a bent or deformed arrangement of stratified (layered) rocks.

These rocks may be of sedimentary or volcanic origin. Although stratified rocks are normally deposited on the earth's surface in horizontal layers, they are often found inclined or curved upward or downward.

Arches, or upfolds, in stratified rock are called anticlines.

Depressions or downfolds are called synclines.

Folds are commonly formed at some distance below the surface, but complete folds or portions of folds are exposed by erosion.

Anticlines frequently have their crests eroded, till only the worn-down stumps of the two limbs remain.

In a similar manner synclines may be eroded so that only the edges of the limbs project above the surface.

The immediate cause of folding is generally conceded to be the horizontal compression of the earth's surface, anticlines being squeezed up by this compression and synclines formed between anticlines.

Porous and permeable rocks of anticlines often contain oil and gas reservoirs.

Credit for the definitions above is granted to The Columbia Electronic Encyclopedia, Sixth Edition Copyright © 2003, Columbia University Press. Licensed from Columbia University Press. All rights reserved. www.cc.columbia.edu/cu/cup/

Call me if you've got any questions. There are no obligations.

Ami Adini
Ami Adini & Associates, Inc.
Environmental Consultants
Underground Storage Tank Experts
323-913-4073; 323-667-2336 fax
mail@amiadini.com
www.amiadini.com

Ami Adini is a mechanical engineer, California Registered Environmental Assessor, Level II, and president of AMI ADINI & ASSOCIATES, INC. (AA&A), an environmental consulting firm specializing in all phases of environmental site assessments, rehabilitation of contaminated sites and upgrading of underground storage tank facilities. AA&A supplies practical solutions to environmental concerns using the highest standards of ethics and integrity while providing its clients with maximum return on their investments.