1 chapter one introduction

ENGINEERING GEOLOGY CVLE 231

CHAPTER 1

1.1 Geology Geology has been defined as “the science which treats of the origin, history and structure of the earth, as recorded in the rocks together with the forces and processes operating to modify the rocks”

Geology was a descriptive science, geologists studied rocks in the field ,recorded the results and deduced the observations.

Geology has made headway in the last two centuries : • Quantitative science instead of descriptive • Laboratory and field testing (instrumentation, analysis…) 1.2 Geology branches Cosmogony: is the study of the relation of the earth to the solar

system and universe. It considers also the origin and early stages of terrestrial sphere

Introduction

Physical Geology: concerned with understanding the composition of the earth and the physical changes occurring in it, based on the study of rocks, minerals, and sediments, their structures and formations, and their processes of origin and alteration.

Paleontology: is the study of prehistoric life, it includes the study

of fossils to determine organisms evolution and interactions with each other and their environments

Mineralogy: it deals with the crystal form, chemical composition,

and physical properties of minerals, which are the native elements constituting the inner mass of the earth and the meteoric bodies.

Seismology: is the study of earthquakes Vulcanology: is the study of volcanoes

Glacial Geology: study of glaciers deposits and action Engineering Geology: geology and engineering;

1.3 Aim of Geology

The practical problems that require the application of geology are: 1-the utilization and management of natural resources: The extraction of petroleum, natural gas, and other mineral resources Coal mining Managing the utilization of water resources to ensure their availability in the future… 2-Environment Climate change due to increasing concentrations of greenhouse gases in the atmosphere is accelerating the melting of glaciers and

therefore driving mass extinctions Managing industrial and domestic waste disposal and minimizing or

eliminating effects of pollution. 3- Geologic Hazards defining and mitigating exposure of natural hazards on humans: flood control, landslides, earthquakes, tsunamis. 4- Earth history

1.2 Engineering Geology

In 1928, St Francis Dam in Southern California Failed, the civil engineering awoke to the idea that the careful design of a structure itself is not all that is required for the safety, it became essential to consult geologists. In their turn, the geologists had become acquainted with engineering requirements Thus, a new type of specialist – the engineering geologists - appeared Engineering geology is the application of geological data, techniques and principles to the study of rock, soil materials, and ground water to assist the engineer in the solution of problems. Purpose: The engineering geology Serves civil Engineering in : Locating and characterizing geologic resources for construction:

Aggregates, fills and borrows. stable foundations and slopes Investigating geological hazards

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DIFFICULT GROUND CONDITIONS

Problems

Settlement

Failures

Land Slide

Rock slope stability

Liquefaction Flood

Volcanoes

Earthquakes