CORE LOGGING Flashcards
(28 cards)
A _______is a cylindrical section of rock, or fragment thereof, taken as a sample of the interval penetrated by a core barrel and brought to the surface for examination and for analysis.
Core
. All drill hole data gathering is called ___________-
logging.
provides data and parameters necessary for mass classification and should be conducted so that the data can be easily applied to all industry standard classification systems.
Geotechnical core logging
- is a barrier that stops or restricts the flow of water or underground streams. Reservoir created by dams not only suppress floods but also provide water for activities such as irrigation, human consumption, industrial use, aquaculture, and navigability
DAMS
At the proposed dam site of the river valley is narrow, only a small dam is required, which means the cost of the dam construction will be less. On the other hand, if the valley is wide, a bigger dam is necessary which means the construction cost will be very high.
Narrow River Valleys
To ensure its safety and stability, a dam has to necessarily rest on (physically) very strong and (structurally) very stable (i.e. bedrocks).
Occurrence of the bedrock at the shallow depth
If igneous rocks occurs at selected dam site, they will offer a safe basis, and weak sedimentary rocks, particularly sahle’s, poorly cemented sandstones and lime stones are naturally undesirable to serve as foundation rocks.
Competent rocks to offer a stable foundation
For the stability of a dam, the occurrence of favorable geological structures is a very important requirement. Under structural geology, we have learnt that those rocks bear certain inherent or original physical properties, such characters get modified either advantageously when geological structures occurs in those rocks.
- Proper geological structures
___________ disposes the surplus river discharge. The capacity of the spillway will depend on the magnitude of the floods to be by-passed. The _______ is therefore much more important on rivers and streams with large flood potential.
spillway
If dam is situated in an earthquake zone, its design must include earthquake forces. The type of structure best suited to resist earthquake shock without danger are earthen dams and concrete gravity dams.
- Earthquake zone
is an underground passageway, dug through the surrounding soil/earth/rock and enclosed except for entrance and exit, commonly at each end. A pipeline is not a tunnel, though some recent tunnels have used immersed tube construction techniques rather than traditional tunnel boring method.
TUNNELS
are sometimes the natural traps of natural gases, which might be harmful to the persons working in tunnels
FOLDS
The orientation of the_______ in relation to tunnel line is vitally important since this govern the length of tunnel affected by the faults and its accompanying fault zones.
faults
are structural plane of weakness and greatly affect shear strength of properties of rocks and rocks masses.
JOINTS
The presence of groundwater is recognized as a major hazard in addition to causing operation difficulties in respect of tunnel construction works.
Groundwater conditions
- a type of displacement into an excavation due to stress gradient created around the tunnel by excavation.
SQUEEZING
- is a time dependent process and involves physico-chemical reactions with water.
SWELLING
-This is often saturated and the presence of water can courage liquefaction when disturbed by tunnelling activities.
Can arise at a later stage due to the progressive collapse and formation of a significant cavity tapping a major aquifer and overlying unconsolidated saturated deposits.
Running Ground
-____-are frequently in the sedimentary rock.
Organic-rich sedimentary rocks have significant amounts of
-organic material generally in the excess of the total organic carbon.
Gases
-Temperature increases about 10 °C for every 60-80 meters in geologically stable areas and 10 °C for 10-15 meters in volcanically active areas.
Effective ventilations is perhaps the only mean to alleviate the problem.
-
Rock temperature
The arrangement of the natural and artificial physical features of an area.
-Topographic conditions
is a structure with a roof and wall standing more or less permanently in one place, such as a house or factory. Buildings come in a variety of sizes, shapes, and functions, and have been adapted throughout history for a wide number of factors, from building materials available, to weather conditions, land prices, ground conditions, specific uses, and aesthetic reasons.
A building, or edifice
is a structure with a roof and wall standing more or less permanently in one place, such as a house or factory. Buildings come in a variety of sizes, shapes, and functions, and have been adapted throughout history for a wide number of factors, from building materials available, to weather conditions, land prices, ground conditions, specific uses, and aesthetic reasons.
building, or edifice
are the building blocks of landscapes, so measuring the morphometric properties of landforms can help evaluate how and why the physical attributes of landscapes vary over time and space.
General Landforms
