The U.S. Geological Survey’s Hawaiian Volcano Observatory (HVO) recorded a magnitude-4.4 earthquake located beneath KÄ«lauea Volcano’s south flank on Sunday, December 20, at 10:36 p.m. HST.
The earthquake was centered about 14 km (8.7 miles) south of Fern Forest, near the HÅlei Pali area of Hawaiāi Volcanoes National Park at a depth of 6 km (4 miles). A map showing its location is posted on the HVO website at http://volcanoes.usgs.gov/hvo/earthquakes/. More details are available at the National Earthquake Information Center website at https://earthquake.usgs.gov/earthquakes/eventpage/hv72294777/
Weak to light shaking, with maximum Intensity of IV, has been reported across the Island of Hawaiāi. At that intensity, significant damage to buildings or structures is not expected. The USGS “Did you feel it?” service (http://earthquake.usgs.gov/dyfi/) received over 500 felt reports within the first hour of the earthquake.
Why did this video talk about volume? What volumes are important for volcanoes?
What angles did this video talk about? Why are these angles important?
Do you trust the evidence in this video? Why or why not?
Live Tour of Eruption Dec 20 at 5am ET (highlighted)
December 21 Volcano Update
December 23 Update
The volcano is now filling up the caldera (the hollowed out top of a volcano). There are some cool volume ideas here. Note that they discuss “cubic feet” and “gallons”. These are two measurements of space that you can see easily around you. (How could you make a 1 cubic foot space?)
Christmas Update
Volcanoes don’t stop on holidays! The lava lake is now 44 stories tall! Check out this cool page from the U.S. Geologic Service that shows cool pictures and a slider:
The recent update does a good job showing what has changed. I was most surprised by the rocky island floating in the middle of the lava pool. I hadn’t heard of that before!
December 27 Update and Video STEM Lab
The lava dropped 7 feet today! (Listen closely to figure out why.) I thought it was interesting that the lava fountains are spraying 32 feet into the air. That’s like throwing a football over a house but instead of a football it’s a molten boulder!
This lab may not have the coolest beginning but the set up is interesting and the result is very cool.
They say it’s “active”, but it’s more lazy these days!
Overview of Kilauea
A short video explaining the 2018 Kilauea lava outpouring. The end of the video talks about their “Volcano Day” thought experiment which is their make-believe way of getting people to pay attention to volcanoes.
This TV show highlights the people that study and document the volcano. It’s cool because they get right up to the lava, and the way they work with the lava helps us understand what lava really is. (Big idea question: Why is it called “living Earth”?)
This shorter video from the Smithsonian Channel shows how the lava is created and moves deep within this volcano.
Although we think of tall volcanoes, the lower rift area of Hawaii reminds us that the lava finds many ways to create new land on the surface.
This week we are going to focus on different perspectives of the founding of Virginia as a colony in 1607. Here are some resources we will use to explore these perspectives.
This cloud presentation might be cool for some, but I am betting you can do it better. Check out this information. There are great pictures (and weird owls).
Create a slide deck with pictures, sentences, and maybe even tables or lists with the info. Make it cooler! You can use Google Slides and send us the link or create a PowerPoint and upload the file below.
This video is from an expert at the Weather Channel describes weather maps and how weather works. All in 4 minutes! If you do not know any of these words, write them on a piece of paper and we can talk about them this week.
If you have left DC to come back to Virginia, you see the taller buildings in Rosslyn. If you were watching this Skyline yesterday, you saw a dramatic change! This video from yesterday shows the destruction of one of the largest hotel buildings (ex-hotel building!!) in our area.
This video is an implosion becomes the destruction was carefully designed so the building fell inwards. An explosion would have pushed the pieces away. Too dangerous!
Demolition experts demolish old buildings, homes, and structures using explosives in the safest and most efficient ways possible. Deductive reasoning and manual dexterity are important skills required to succeed in this profession. Check out the following table for more details.
Common Education
High school diploma or equivalent
Key Skills
Operation and control, judgment and decision-making, time management, coordination, and monitoring skills
Training Required
Long-term on-the-job training
Work Experience in a Related Occupation
Less than 5 years
Licensure/Certification
Vary by state
Job Outlook (2018-2028)
6%* (for all explosives workers, ordnance handling experts, and blasters)
Average Annual Salary (2018)
$52,780* (for all explosives workers, ordnance handling experts, and blasters)
Source: *U.S. Bureau of Labor Statistics
What Does a Demolition Expert Do?
Demolition experts, also known as explosive workers, ordnance handling experts, and blasters, are responsible for dismantling, razing, wrecking or demolishing any structure or any part thereof. Their work also often involves loosening, removing, or displacing earth, rock, or other materials using explosives. Their day-to-day tasks include inspecting blast areas to ensure safety laws are being followed; determining the quantity and type of explosives needed; coordinating the time sequences of the explosions; keeping the records according to local and federal laws; and setting up, maintaining, and operating various pieces of equipment.
Do I Need a Degree?
The typical education entry requirement for demolition experts is holding a high school diploma or equivalent. Although a traditional college degree is not required for this profession, employers may prefer their demolition experts to possess a post-secondary certificate, vocational school training, or bachelor’s degree related to construction management.
What Are the Training Requirements?
Most demolition experts train on the job under an experienced demolition expert. On-the-job training can last between a few months to one year. Alternatively, the necessary training is also provided by labor unions, vocational training schools, and contractor associations through specialized apprenticeship programs.
Possessing work experience in a related occupation, preferably in the construction industry, is another requisite for becoming a demolition expert. Since this profession requires a high level of supervision and responsibility for others’ safety, generally around 4 to 5 years of work experience in a related occupation is required.
Do I Need to Be Licensed or Certified?
Although license and certification requirements vary from one state to another, demolition experts are required to hold a federal license to remove asbestos, lead-based paint or other hazardous material. This license is obtained by completing the OSHA (Occupational Safety and Health Administration) certification course. Some states might require demolition experts to obtain state-mandated safety certification by clearing a test before they can start working with explosives. Other states might require demolition experts to obtain permits based on the size of the structure they plan on demolishing.
How Much Might I Earn?
According to the U.S. Bureau of Labor Statistics, explosives workers, ordnance handling experts, and blasters earned an average annual salary in 2018 of $52,780. Demolition professionals who worked in top paying industries earned an average annual salary around $70,000 and up. In 2018, the top paying industries for this occupation were heavy and civil engineering construction; management, scientific, and technical consulting services; and scientific research and development services.
Feeling the need for more Demolitions? Check this out!!
This article from BigRentz Breaks Down the Destructive Details (link)
Demolition is probably one of the most interesting parts of construction work. As we build more structures, there comes a point where we need to demolish old ones, either for safety reasons or to make room for newer buildings.
Demolition is the process of dismantling a building by pre-planned or controlled methods. However, thereās more to demolition than swinging a wrecking ball ā it involves highly trained experts working with debris, weather conditions, materials, mass, and physics. Methods vary accounting to the type of building that is being demolished.
As the construction industry continues to see growth, demolition work is expected to grow at a rate of 3.3% through 2022. Read on to learn about the science behind demolishing a building and why itās an important part of our communities. Jump to our infographic below to see a summary of the entire demolition process.
Pre-demolition Process
Before a demolition is executed, the experts must consider several different factors. A demolition process is customized for each project and typically involves the following steps.
Building survey: Experts examine the different characteristics of a building, such as the materials, building usage, method of construction, condition, draining conditions, traffic conditions, building codes, and neighboring communities. A study of these parameters will help to dictate the best demolition method.
Removal of hazardous materials: Specialized personnel is called upon to remove dangerous materials from the building prior to demolition, such as asbestos minerals, radioactive substances, flammable materials, and petroleum contamination.
Demolition plan: Experts craft a detailed plan illustrating what will be involved in the demolition, how it will be carried out, the equipment that will be used, and how much debris they will need to clean up.
Safety measures: Site workers, supervisors, operators, and engineers are advised of potential hazards such as flammable materials and exposure to noise and dust. The demolition company must also secure the proper permits.
The next step is to select the safest and most efficient demolition method that stays within budget. Not all demolitions end in explosions ā methods can range from devastating blasts to non-explosive piece-by-piece removals. Some include implosions, excavators, wrecking balls, bulldozers, and selective demolition.
Building Implosion
Implosion is by far the most impressive method of demolishing a building. However, due to their specialized nature, implosions are used in less than 1% of demolition projects. Implosion is the process of using explosives to knock out a buildingās main supports, causing the building to collapse from the inside out.
Buildings are imploded in one of two ways. If space permits, explosives are fitted into the buildingās left columns, making it fall to the side when detonated. Cables are often used to control the buildingās collapse, making this method a safer option. If space is limited, the second method involves placing explosives in the buildingās lower support system and middle sections, causing the building to fall onto itself.
Implosions require the knowledge of experts called āblastersā and are often used to demolish large structures in urban areas. A successful implosion requires the following steps:
Blueprint examination: Blasters study blueprints of a building to determine which areas need to be blasted.
Site preparation: Crews prepare a site by taking out the non-load-bearing walls, weakening supporting columns, and wrapping columns with fencing for a cleaner fall with less flying debris.
Determine explosives: Blasters select an explosive based on the buildingās materials. Dynamites release shockwaves and are best used to obliterate concrete columns. RDX can expand up to 27,000 feet per second to slice through steel structures.
Load explosives: The explosives are bored into columns, generally in support columns and a few upper stories to make it easier to break the building into smaller pieces.
Time detonation: Blasters first build up an electrical charge. When the current is sent through the wire, it heats up and ignites the flammable substance, setting off the main explosives. Blasters can time their detonations by setting slow-burning materials to delay the explosions.
Questions
Watch the Rosslyn video closely. Where do you think the explosives placed?
The video shakes initially. What is happening when the videographer shakes? Create a timeline that organizes the details in order!
