Impending Signs Landslide 3g5p50

http://inspectapedia.com/vision/Sink_hole_ Detection.php

https://www.earthtech.com/reside ntial/sinkhole-truth/sinkholewarning-signs/

1. Bulging ground appearing at the base (toe) of a slope or retaining wall. 2. Water breaks through the ground surface in new location. 3. Fences, retaining walls, utility posts or trees tilt or move. 4. Cracks appear on slope.

5. Water pipes break. 6. Cracks appear on the ground or in the foundation of houses, buildings and other structures. 7. Doors and windows become stuck or jammed for the first time.

8. Water appear at the base of the slope. 9. Slowly widening cracks appear on the ground or on paved areas such as paved streets, driveways and concreted path ways. 10. Land movements and debris downslope. 11. Outside walls, walks or stairs being pulling away from the building.

SINKHOLE

Read to Learn

◦I. What are sinkholes? Try paraphrasing in your own words ◦ II. In what type of geologic conditions do sinkholes occur? What is Karst? ◦III. What are the different types of sinkholes and what are the major differences regarding the rate they can occur. ◦IV. What are some man made causes of sinkholes?

https://water.usgs.gov/edu/sinkhole s.html

◦I. What are sinkholes? Try paraphrasing in your own words ◦ II. In what type of geologic conditions do sinkholes occur? What is Karst? ◦III. What are the different types of sinkholes and what are the major differences regarding the rate they can occur. ◦IV. What are some man made causes of sinkholes?

◦I. What are sinkholes? Try paraphrasing in your own words ◦ II. In what type of geologic conditions do sinkholes occur? What is Karst? ◦III. What are the different types of sinkholes and what are the major differences regarding the rate they can occur. ◦IV. What are some man made causes of sinkholes?

Sinkholes

 are depressions or openings in the ground surface. They are generally formed as the result of a collapse in the ceiling of an underground cavity or cavern. typically develop slowly, but can also form suddenly when a collapse occurs.

Sinkholes naturally occur in areas underlain by soluable carbonate or evaporite rocks like limestone, dolomite, gypsum, and salt.

The three types of sinkholes are: 1. Dissolution sinkholes; 2. Cover-subsidence sinkholes; 3. Cover-collapse sinkholes.

Dissolution sinkholes  occur where there is little soil or vegetation over the soluble rock.

Aggressive disssolution occurs where flow is focused in pre-existing openings in the rock , such as along ts, fractures, and bedding planes, or in the zone of water – table fluctuations where the ground water is in with the atmosphere. They typically develop gradually.

Cover-subsidence sinkholes tend to develop gradually where the covering sediments are permeable and contain sand.

Cover-collapse sinkholes tend to develop abruptly and cause catastrophic damages. They occur where the coverning sediments contain significant amounts of clay.

Karst terrain  type of topography that is formed by dissolution of bedrock in areas underlain by limestone, dolostone or, as in some western states, gypsum. Such terrain has underground drainage systems that are reflected on the surface as sinkholes, springs, disappearing streams or even caves.

Type of Sinkholes

Resilience

Quiz

◦1. What is sinkhole? ◦2. Give 2 types of sinkholes and explain each. 3. Give 2 causes of sinkholes and explain each.