Ecology

Geology

Is the natural science that studies the Earth-its composition; the processes that shaped its surface and its history.

Rock

Earth is made up of

Minerals

Rocks are composed of

Atoms

Mineral are composed up of

Geomorphology

Is that branch Geology that deals with the origin, nature and **distributions of landforms**

Physiography

refers to the **description of landforms**

Landforms

are irregularities on the earth’s surface. They are derived from volcanic, glacial or erosional processes.

Texture

are generally the most meaningful; from them we can make inferences about **bearing capacity, internal drainage, erodibility and slope stability**

Composition

refers to material that makes up soil : mineral particles, organic matter, water and air.

Mineral Particles

comprise 50% to 80% of the volume of the soil and form the all important skeletal; structure of the soil.

Sand and Gravel Particles

provide for the greatest stability , **usually yield a relatively high bearing capacity**

Bearing Capacity

Is a soil’s resistance **to penetration from a weighted object** such as Building Foundation.

Organic Matter

varies radically in soils and usually imposes a limitation to any building structure. and it is important only for soil fertility, moisture absorption and retention and for landscaping.

Water

content varies with particles sizes, local drainage, topography and climate.

Air

Is what occupies remaining spaces that is not occupied by water.

Good Drainage

Refers to the soils ability to transfer gravity water downward

Infiltration

the rate at which **water penetrates the soil surface**

Permeability

the rate at which water within the soil moves **through a given volume of material**

Percolation

the rate at which water in __a soil pit or pipe__ **within the soil is taken up by the soil.**

Poor Drainage

means that gravity water **is not readily transmitted** by the soil and soil is frequently or permanently saturated and may have water standing on it caused.

Slope Analysis

• understanding slope forms for site design requires understanding of local geologic, soil, hydrologic and vegetative conditions

• Is an important analytical process made on a topographic map that makes a proper match between land uses and slopes and produces and overall pattern of slopes which helps the site planner in determining the buildable portions of the site.

Slope Form

is expressed graphically in terms of slope profile, **a silhouette of a slope drawn to known proportions with distance in the horizontal axis and elevation on the vertical axis.**

Angle of Repose

**angle** at which soil can be **safely inclined and beyond which it will fail**

Topographic Map

a map of a portion of the earth **that describes the shape of the earth’s surface by** __**contour lines.**__

Contours

are **imaginary lines** that join points of equal elevation on the surface of the land above or below a references surface such as the mean sea level.

0%-5%

Generally Flat or Highly buildable

5-10%

Gently rolling or Moderately buildable

10-15%

Gentle to mild slopes or Moderately difficult to build

15-20%

Mild to steep slopes or Difficult to build

20 and over

Harsh , steep slopes or Unbuildable

Slope map

is prepared to visually express slope patterns on the topographic map

Desirable slope

when slopes are selected **according to building type** and the activities associated with it.

Flat or gently sloping sites

are preferred for **industrial and commercial buildings**

Hilly Sites

are preferred for **fashionable suburban residences.**

Soil Erosion

when rocks are **broken down into small fragments** and carried by wind, water , ice and gravity.

Hydrology

The natural science that studies the **waters of the earth**, their occurrence, circulation and distribution and their reaction to the living environment including their relation to all living things.

Hydrological Cycle

also known as the planet’s water cycle. described by the movement of water from the oceans to the atmosphere to the continents and back to the sea.

Water Table

is the **upper boundary of the zone of groundwater;** the top of unconfined aquifer

Aquifer

a permeable geological stratum or formation that can both store and transmit groundwater in significant aquifers.

Watershed

a geographic area of land bounded by topographic features and height of land **that captures precipitation filters** and stores water and drains waters to a shared destination.

Solar Radiation

Is earths source of light and heat. It warms the earths surface , is reflected by paving and other objects and produces glare.

Wind

helps to control temperature. when winds are of low velocity, they may be pleasant , but when velocity increases, may cause discomfort or damage

Precipitation

Plants help to control precipitation reaching the ground.

Air purification

plants clean air through the process of photosynthesis where they use up carbon dioxide emissions of cars and trucks and in the process release oxygen into the air.

60 decibels

the sound level of normal conversion is about:

Open Wildlife

includes birds and mammals commonly associated with cropfield, meadows, pastures and non forested lands

Woodland Wildlife

These species needs various combinations of:

• Grasses and legumes

• Wild herbaceous upland plants

• Hardwood woody plants

  • Cone-bearing shrubs such as pines

Wetland Wildlife

it includes birds and mammals needing habitat with a :

• Wetland food plants or wild herbaceous plants of moist to wet sites, excluding submerged or floating aquatic plants

• Shallow water development with water impoundments not deeper than 5ft.

• Excavated ponds with ample supply if water at least one acre and average 6ft depth

  • Streams.

Abrupt forms

cause unpleasant air turbulence

Angle of Incidence

**affects area over which energy of light is dissipated;** the depth of area penetrated, and the amount of light energy that is reflected by airborne particles without reaching surface.

Adiabatic Cooling

when air at equator cools as it rises **resulting in lower capacity to hold water,** __**thereby raining heavily at equator.**__

Adiabatic Cooling

when the circulation pattern of __**HADLEY CELLS**__ **causes rising air to spread in upper atmosphere, cool and eventually drop back to surface in a water-depleted condition** that allows it to gain capacity to hold water as __**it drops and warms the air.**__

Coriolis Force

also known as conservation of momentum, which superimposes major easterly and westerly patterns **in winds blowing N and S within Hadley Cells.**

Sand dunes

are mounds or ridges of sand deposited by wind and **the most significant landforms created by wind.**

Transverse dunes

**form a wavelike ridges transverse to wind direction.** They develop where wind direction is constant in areas where the supply of sand is large and with little vegetation

Barchan dunes

**are crescent-shaped dunes with horns pointing downwind**. they form on hard flat desert floors where wind direction is constant and supply of sand is limited. height from 1.0 m to 30.0 m

Longitudinal dunes

**long straight, ridges shapes dunes parallel with wind direction.** Occurs in desert with scanty sand supply and result from two slightly different wind directions and are elongated in the direction of the prevailing wind. **Grow up to 100 m high and 100.0 km long.**

U-shape dunes

**are u-shape with open side of the u facing upwind**. some form by piling of sand along leeward and lateral margins of a growing ”blowout” in older dunes.

Blowout

is a deflation basin excavated in shifting sand

Star dunes

**have a high central point from which tree or four ridges extend like spokes of a wheel**. they result from winds blowing in tree or more directions.

Parabolic Dunes

Known as Beach Dunes , **hummocks of various sizes develop along the coast from strong on-shore winds**. Inland part is generally covered with vegetation.

Earthquake

AS the plates move, strain accumulates causing faults along plate boundaries to slip abruptly and the resultant release of stress is called an

Intensity

it describes the degree of shaking at specified place

Modified Mercalli scale (MM)

most widely used scale in earthquakes (intesity)

Richter Scale (M)

The most commonly used scale is the________ (magnitude)

Fault

is a fracture along which differential movement of rock has occurredF

Fault displacement

is defined **as the differential movement of two sides of the fault at the earths surface**

Tectonic creep

refers to slow differential slippage of two sides of the fault.GR

Ground Shaking

refers to the vibration of the ground occurring during earthquake.

Seismic engegy

Is released by earthquakes with foci less than 60 km deep.

P waves

cause vertical movement of structures

S waves

cause side to side vibration of buildings

Surface waves

these waves are of lower frequencies than P and S waves and more inclined to cause tall buildings to vibrate

Accelograph

**is an instrument that measure the amount of acceleration of ground shaking**, in terms of percentage of force of gravity. Shaking in excess of 10 percent is damaging to buildings.L

Liquefaction

is a physical process which causes three damaging types of ground failures and **causes soil deposits to lose strength temporarily and behave as viscous fluids rather than solids.**

Lateral spreads

refers to the generally horizontal movement of large blocks of soil.

Flow Failure

occurs when liquefied soil or block of intact material are transported on a layer of liquefied soil and **the most catastrophic type of ground failure caused by liquefaction.**

Loss of bearing strength

can cause large buildings to settle and tip and are particularly damaging when a layer of saturated non-cohesion less materials extends from the ground surface to a depth approximately the width of the building.

Seismic Hazards

the physical effects of tectonic activity such as ground shaking and soil failures

Seismic Risks

the exposure of individuals and objects to potential injury or damage from seismic hazards.

Design Earthquakes

is a hypothetical event used **as a basis for assessing seismic hazards.** it establishes the expected maximum magnitude and location, which in turn establishes the extent and severity of various seismic hazards

Seismic Zonation

**predicts the effects of the design earthquake**, delineating geographical areas with potentials for surface faulting, ground shaking, flooding, liquefaction and landsliding.

Landslides

**the downward and outward mass movement** of rock, soil, artificial soil, artificial fill or a combination of these materials and slope movement results from the action of gravity and climate on geological materials,

Mass movement

where debris moves as a coherent unit

Particle movement

where particles move as individuals, with little or no relation to other particles.

Main scarp

a steep surface on the undisturbed ground around the periphery of the slide caused by the movement of slide material away from undisturbed ground. the projection of the scarp surface under the displaced material becomes the surface of rupture.

Minor Scarp

a steep surface on the displaced material produced by deferential movement within the sliding mass

Head

the upper parts of the slide material along the contact between the displaced material and the main scarp.

Top

the highest point of contact between the displaced material and the main scarp

Toe of surface of rupture

the intersection between the lower part of the surface of rupture and the original ground surface

Landslide Susceptibility Map

is useful for ascertaining landslide potential of a region, but may not be used for assessment of a particular site.

Zoning

which can restrict intensive development and /or prohibit land uses that would be vulnerable to landslide damages

Subdivision Regulations

which can require that landslide hazard areas be identified and reserved for open-spaces uses

Sanitary Regulations

which can restrict the use of on-site water-based sanitary disposal systems which can trigger landslide by wetting vulnerable areas

Special regulations for hillsides

identified as landslide-prone areas which can establish the appropriate grading practices and call for preservation of protective vegetation

excavation

can be one of the least expensive methods for stabilizing a slope

Drainage

which both reduces shearing stresses and increases shear resistance

Restraining structures

which increases shearing resistance, these should be considered as last resort , as they often expensive and employed only when there are no other alternatives

Landslide subsidence

any displacement of a generally level ground resulting form surface or subsurface causes.

Surface Loading

causes compaction of compressible materials