full transcript
"From the Ted Talk by Liz Hajek: What rivers can tell us about the earth's history"

Unscramble the Blue Letters

So you can imagine in landscapes like this, where rivers move around fnerltuqey, it's really important to understand when, where and how they're going to jump. But these kinds of processes also heppan a lot closer to home as well. So in the uitned States, we have the msssippiisi River that drains most of the continental US. It pushes material from the Rocky Mountains and from the Great plians. It drains it and moves it all the way across America and dumps it out in the Gulf of Mexico. So this is the course of the Mississippi that we're familiar with today, but it didn't always flow in this deioritcn. If we use the geologic rrcoed, we can reconstruct where it went in the past. So for example, this red area here is where we know the Mississippi River flowed and deposited material about 4,600 years ago. Then about 3,500 years ago it meovd to follow the course oiutnled here in orange. And it kept moving and it keeps moving. So here's about 2,000 years ago, a thousand years ago, 700 years ago. And it was only as recently as 500 yreas ago that it occupied the pathway that we're familiar with today. So these peseocrss are really important, and especially here, this delta area, where these river-jumping events in the Mississippi are building land at the interface of the land and the sea. This is really valuable real estate, and deltas like this are some of the most dnsleey populated areas on our planet. So understanding the dynamics of these landscapes, how they formed and how they will cuninote to change in the future is really important for the people that live there.

Open Cloze

So you can imagine in landscapes like this, where rivers move around __________, it's really important to understand when, where and how they're going to jump. But these kinds of processes also ______ a lot closer to home as well. So in the ______ States, we have the ___________ River that drains most of the continental US. It pushes material from the Rocky Mountains and from the Great ______. It drains it and moves it all the way across America and dumps it out in the Gulf of Mexico. So this is the course of the Mississippi that we're familiar with today, but it didn't always flow in this _________. If we use the geologic ______, we can reconstruct where it went in the past. So for example, this red area here is where we know the Mississippi River flowed and deposited material about 4,600 years ago. Then about 3,500 years ago it _____ to follow the course ________ here in orange. And it kept moving and it keeps moving. So here's about 2,000 years ago, a thousand years ago, 700 years ago. And it was only as recently as 500 _____ ago that it occupied the pathway that we're familiar with today. So these _________ are really important, and especially here, this delta area, where these river-jumping events in the Mississippi are building land at the interface of the land and the sea. This is really valuable real estate, and deltas like this are some of the most _______ populated areas on our planet. So understanding the dynamics of these landscapes, how they formed and how they will ________ to change in the future is really important for the people that live there.

Solution

  1. processes
  2. united
  3. densely
  4. plains
  5. outlined
  6. moved
  7. mississippi
  8. years
  9. record
  10. continue
  11. direction
  12. frequently
  13. happen

Original Text

So you can imagine in landscapes like this, where rivers move around frequently, it's really important to understand when, where and how they're going to jump. But these kinds of processes also happen a lot closer to home as well. So in the United States, we have the Mississippi River that drains most of the continental US. It pushes material from the Rocky Mountains and from the Great Plains. It drains it and moves it all the way across America and dumps it out in the Gulf of Mexico. So this is the course of the Mississippi that we're familiar with today, but it didn't always flow in this direction. If we use the geologic record, we can reconstruct where it went in the past. So for example, this red area here is where we know the Mississippi River flowed and deposited material about 4,600 years ago. Then about 3,500 years ago it moved to follow the course outlined here in orange. And it kept moving and it keeps moving. So here's about 2,000 years ago, a thousand years ago, 700 years ago. And it was only as recently as 500 years ago that it occupied the pathway that we're familiar with today. So these processes are really important, and especially here, this delta area, where these river-jumping events in the Mississippi are building land at the interface of the land and the sea. This is really valuable real estate, and deltas like this are some of the most densely populated areas on our planet. So understanding the dynamics of these landscapes, how they formed and how they will continue to change in the future is really important for the people that live there.

ngrams of length 2

collocation frequency
warming event 4
million years 4
kosi river 4
shaped pathway 3
satellite image 3
rivers change 3

Important Words

  1. america
  2. area
  3. areas
  4. building
  5. change
  6. closer
  7. continental
  8. continue
  9. delta
  10. deltas
  11. densely
  12. deposited
  13. direction
  14. drains
  15. dumps
  16. dynamics
  17. estate
  18. events
  19. familiar
  20. flow
  21. flowed
  22. follow
  23. formed
  24. frequently
  25. future
  26. geologic
  27. great
  28. gulf
  29. happen
  30. home
  31. imagine
  32. important
  33. interface
  34. jump
  35. kinds
  36. land
  37. landscapes
  38. live
  39. lot
  40. material
  41. mexico
  42. mississippi
  43. mountains
  44. move
  45. moved
  46. moves
  47. moving
  48. occupied
  49. orange
  50. outlined
  51. pathway
  52. people
  53. plains
  54. planet
  55. populated
  56. processes
  57. pushes
  58. real
  59. reconstruct
  60. record
  61. red
  62. river
  63. rivers
  64. rocky
  65. sea
  66. states
  67. thousand
  68. today
  69. understand
  70. understanding
  71. united
  72. valuable
  73. years