FAULTS OF THE BIG WILD

[Audio] Hello there, Buddy! It's your pal, here! So, you're thinking about moving to Anchorage? Excellent! Well, because you had some concerns about life on a fault line, potential disasters, and land features of the region, I decided to put together a presentation for you. Let's get started!.

[Audio] I'll kick things off with geography. Anchorage is located in the US state of Alaska. It sits approximately at 61 degrees N latitude and 149 degrees W longitude. Its elevation is 102 ft above sea level. Its cardinal borders include the Knik Arm and Point Mackenzie to the north, Kenai Peninsula to the south, coastal mainland Alaska to the east, and Chickaloon Bay to the west. Anchorage is the county seat of a consolidated city-borough..

[Audio] Regional landforms surrounding Anchorage include Cook Inlet, Chugach Mountains, and Talkeetna Mountains..

[Audio] The city of Anchorage lies in the southern edge of Alaska-Aleutian megathrust. The fault is located on the boundary of the Pacific Fault and the North American Fault and spans around 12,000 miles. My research showed that the Denali Fault is not a convergent plate boundary in a subduction zone, but rather a transform boundary, a right-lateral strike-slip fault that connects the subduction zone to the continental interior. This means the lithosphere plates slide past one another..

[Audio] The Denali Fault is the primary active fault directly affecting Anchorage. It is a strike-slip fault system which is a high category with average late quaternary slip-rates ranging from about 5mm to 13mm per year..

[Audio] The city itself rests on the Alluvial Plain, which was created by the deposition of sediment over time. It is part of the Ring of Fire in the Pacific where activity is high and home to around 75% of the world's volcanoes and 90% of the world's earthquakes. More earthquakes than the lower 49 US states combined! Including the second largest earthquake ever recorded!.

[Audio] Some historical events include: 2002, the Denali Fault Earthquake. A 7.9 in magnitude. 1964, the Good Friday Earthquake, formally called Great Alaska Earthquake. A 9.2 magnitude and the second largest earthquake ever recorded..

[Audio] Tectonic activity can also leave behind physical manifestations known as geomorphic expressions. These can be landforms and features such as mountains or valleys. Remember that 2002 earthquake I mentioned? It produced a 350 km long "scarp", a visible rupture along the fault, altering the topography of the ground surface..

[Audio] Nearly 75% of Alaska's population lives in areas capable of experiencing a magnitude 7 earthquake. According to the US Geological Survey (USGS), the Castle Mountain Fault in south-central Alaska may be due for another big 6 or 7 magnitude earthquake within the next 50 to 100 years. The Alaska Division of Geological and Geophysical Surveys claiming a magnitude 8+ every thirteen years, one 7 to 8 every two years, and one 6 to 7 annually. Alaska is the highest seismically active state. In my opinion, if plate-related disaster is capable in such a massive state, there really isn't any avoiding it. So, zip up your North Face fleece, start warming your snowmobile, and embrace one of the planet's most unique regions to call home..

[Audio] So, there you have it! I hope this helped you in reaching a decision. Thank you for watching!.