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1. Did the cave dwellers see the dinosaur? If no why?
Cave man did not see the dinosaur. This is because the two existed during different times in history. While the earliest evidence of man living in caves can only be dated back to 2,000,000 years ago, dinosaurs can be traced back as early as 200 million years.
2. What is the most convincing evidence of sea floor spreading?
In the earlier years, the main evidence was the matching fossils at different parts of the sea floor at the opposite ends of the Atlantic Ocean. Today, there has been accurate measurements made by GPS devices that show that the seafloor is really spreading
3. The earth interior is divided into three zones. Name them.
The earth’ interior is divided into the crust, the mantle and the core.
4. The composition of diamond and coal is carbon. What is the difference?
The difference between the two is that while diamond is made of pure carbon, coal is an amorphous carbon which contains impurities. The chemical structure of carbon atoms the two allotropes is different.
5. Continental margins are divided into two types. What are they?
They are the Atlantic type and Pacific type.
6. What is the estimated age of the earth
It is estimated that the Earth is 4.54 ± 0.05 billion years old.
7. Give two evidences provided by Wegner for continental drift
He used the jigsaw fit where he stated that the adjacent continents had margins that would fit into each other if brought together. The second evidence that he gives is the sedimentary rocks in some parts of Africa, Asia, Australia, Arabia and Antarctica are similar. This shows that their formations and origin might have been at the same time and were joined together, only for them to mover apart later.
8. Name the three plate boundaries
The boundaries are convergent, divergent and transform plate boundaries.
9. Name a place in The US where transform plate boundary exists
San Andreas Fault Zone which is located in western North America
10. Name two major mountain belts
They are Appalachian Mountains and the Rocky Mountains
11. Rocky Mountains are higher that Appalachians. What does it tell about their age
The two belts represent eroded mountains. Those that are higher are younger since they are perceived to have been formed later that the lower ones. Appalachian Mountains are therefore older than the Rocky Mountains
12. Most of sedimentary rocks in mountains are of marine origin. What does that indicate?
Mountain formation has its origin from the over thrust of the ocean floor. This over thrust occurs in the craton’s continental crust and not in the oceanic layer that is subducting. When the mountains are therefore formed, they carry the marine sedimentary rocks.
13. Rocks of the continental crust are lighter than oceanic crust
Rocks in the continental crust are less dense hence lighter in weight than those in the oceanic crust, which is basaltic. The weight/density difference results from the fact that continental crust does not subduct hence is lighter as compared to oceanic crust that subducts under slightly less dense crust.
14. Give any two types of stresses that rock undergo
They undergo compression stress and tensional stresses
15. What would folds and reverse faults in a mountain belt suggest
This would suggest that there has been some movement of the layers beneath the crust. Folds would mean that there was a collision of plates whose rock crumble and accumulation leads to the bulging of the plate resulting to the formation of the mountain. A reverse fault would mean that there were forces that acted from opposite directions on the same rock, causing it to develop a fault. As the forces persisted, one of the pieces of broken rock moved over the other causing a sharp bulge on the surface of the earth. Therefore, the presence of any of the two means that there were movements and compressional forces that acted on the rocks at the place.
16. Folds are usually associated with compressive stresses along convergent boundaries-True
17. In a fractured rock if no displacement occurs that fracture is weathering
18. When there is extension of the crust normal faults occur and when there is horizontal compressional stress is applied reverse faults occur
19. The seismic waves are the ones that cause the ground to tremble and shake during an earthquake
False
20. The earthquake waves recording device is called a seismograph and the paper record of the vibration is called the ritcherscale
21. Usually where on the earth surface do earthquakes occur?
On the regions that lie above unstable joints of tectonic plates
22. According to the principle of superposition the layers of rocks get younger going from bottom to top.
23. what are the two types of ages of rocks that geologists talk about
A) Precambrian B) Phanerozoic
24. Give any two conditions that must be satisfied for a substance to be called mineral
Minerals have highly ordered atomic structures, and specific naturally occurring and must be solid and crystalline.
25. Name two groups of minerals
Isomorphs and isotypes
26. What is the hardest mineral and the softest mineral?
Hardest-Diamond, Softest-Talc
27. Name one mineral which has a high specific gravity
Platinum
28. What is the difference between magma and lava
Magma is the molten rock beneath the surface of the earth whereas lava is the magma that reaches the surface of the earth after a volcanic eruption and the resultant rock.
29. What is the range of temperature of magmas?
700 °C to 1300 °C
30. What are two beneficial effects of volcanism?
Formation of rich agricultural soils and formation of mountains and other physical features like craters.
31. Mafic lavas tend to flow easily. Why?
They have a high temperatures of about 9500C thus less viscous
32. What is the predominant gas that is released during volcanic eruption?
Water vapor followed by Carbon dioxide
33. What are the two factors that determine the grain size during the solidification of igneous rocks? Time taken to cool down and the place on the earth that it forms.
34. Which state in the mainland US has the most volcanoes?
Oregon
35. In what kind of places will you find the most volcanic activity and earthquakes?
Places lying above unstable tectonic plates
36. Igneous rocks formed at considerable depth are called
Intrusive igneous rocks
37. Why are plutonic rocks generally coarse grained?
They are formed inside the crust hence cool down slowly which results to a compete formation of grains, making it coarse grained
38. Granite and rhyolite are different in texture
39. What are the two types of weathering
Mechanical and chemical
40. Name two types of mechanical weathering
Fracturing and abrasion
41. The most common end product of chemical weathering of quartz is
Clay
42. What are the controlling factors of mass wasting?
Soils water saturation, slope, and soil age
43. What is the difference between breccia and conglomerate?
Conglomerate- made up of rounded pebbles, Breccia -made up of angular pebbles
44. Name two common sedimentary rocks
Breccia and conglomerate
45. If you see well rounded particles in a sedimentary rock what do they tell about their
Transportation
They were transported through dragging and they were smoothened by the other rocks they hi as they moved downstream.
46. Name three types of rocks
Sedimentary rocks, metamorphic rocks and igneous
47. Give two examples of clastic sedimentary rocks
Sandstone and siltstone
48. Give an example of organic sedimentary rock
Limestone
49. What are the contributing factors for formation of metamorphic rocks?
Earth movement, temperature and pressure
50. The process of metamorphism takes place in solid state only.
True
51. After metamorphism the new rock most commonly will have a distinct new texture
True
52. What are the three foliated textures of a metamorphic rock?
Slaty, schistose and gneissose
53. What is a drainage basin?
It is the whole extent of an area from where surface water from melting snow or rain converging to a single point collects.
54. Name two main tributaries of Mississippi river
Missouri River and Ohio River
55. Name three drainage patterns
Dendritic, rectangular and parallel
56. What are the three types of stream erosion?
The stream may erode material along the banks. On the bed or erode further up from the source to elongate the stream
57. Name two types of sediment transportation
Suspension, fluvial transport
58. Name three types of stream deposits
Dissolved loads, suspended and bed loads.
59. State two things that can cause groundwater pollution
Use of farm chemicals
Deposition of untreated industrial waste
60. What are stalactites and stalagmites?
Stalactites are features formed when water freezes from a crack on the roof of a cave to form fingerlike projections, whereas stalagmites are formed when frozen water deposits on the floor of a cave to form a fingerlike feature from the floor.
61. Define ground water
This is the water located beneath the earth surface
62.The upper limit of zone of saturation is called a water table
63. What is a contour line?
It is a line that joins points with the same elevation on a map
