If you have spent most of your life studying audiology and sound properties, it is quite possible that you will find this post of interest.  In our studies of sound and its uses, most of us do not think about how it can be used to map various characteristics under the surface of the earth or below the sea.  That is our topic this week at Hearing International

Ludger Mintrop (1880-1956) was a German mine surveyor and geophysicist who is considered the inventor of the seismic method for exploration of hydrocarbons and minerals through the seismic refraction method (Patented in 1916).  Born in the Northwest German city of Essen in the 1880, he used his method in WWI to find allied artillery and later to find salt mines and other underground structures and won many accolades and awards for his seminal work in seismic prospecting.  While your fish finder  in that new bass boat uses a variation of sonar technology, Mintrop’s seismology uses some interesting applications of sound propagation to find things and has now become the primary tool of exploration companies in the continental United States, both onshore and offshore. Seismic surveys can help locate ground water, land fill sites and are famous for characterizing how the land will shake in an earthquake but are primarily used for oil and gas exploration as well as research in some parts of the world. Seismic surveys are conducted by creating a shock wave, or a seismic wave, on the surface of the ground along a predetermined line, using an energy source.  The seismic wave that travels into the earth is reflected by subsurface formations and returns to the surface where it is recorded by receivers called geophones a device similar to microphones. Basically, it is a device that converts ground movement (velocity) into voltage, which may be recorded at a recording station. The deviation of this measured voltage from the base line is called the seismic response and is analyzed.  Typically, these seismic waveforms are created either by small explosive charges set off in shallow holes (“shot holes“) or by large vehicles equipped with heavy plates (“Veibroseis” trucks also called thumpers) that vibrate on the ground. By analyzing the time it takes for the seismic waves to reflect off of subsurface formations and return to the surface, a geophysicist can map subsurface formations and anomalies and predict where oil or gas may be trapped in sufficient quantities for exploration activities or even map the bottom of the sea.

Seeing Through the Antarctic Ice Cap

Seismic surveys can be used to map the ocean floor underneath the ice cap in Antarctica.  Applications of these techniques are now being used to see under the ice to map the floor of the ocean with the use of a thumper truck (sometimes called a weight-drop truck).  As an alternative to the use of dynamite as a stimulus generator, the thumper technique was introduced in 1953.   Thumping is usually less damaging to the environment than firing explosives in shot-holes, and its especially useful in politically unstable areas where fracking has significant controversy.  A thumper truck is a vehicle-mounted ground impact system which can be used to provide a seismic source. A heavy weight is raised by a hoist at the back of the truck and dropped, generally about three meters, to impact (or “thump”) the ground. To augment the signal, the weight may be dropped more than once at the same spot, the signal may also be increased by thumping at several nearby places in an array whose dimensions may be chosen to enhance the seismic signal by spatial filtering.  These days, the more advanced Thumpers use a technology called “Accelerated Weight Drop” (AWD), where a high pressure gas is used to accelerate a heavy weight Hammer to hit a base plate coupled to the ground ufrom a distance of 2 to 3 m. Several thumps are stacked to enhance signal to noise ratio. AWD allows both more energy and more control of the source than gravitational weight-drop, providing better depth penetration, control of signal frequency content.

How Does it Work?

Antarctic researchers are interested in the looking at the geological history of the area by finding sediment on the sea floor so it can be sampled to monitor the changes in the future.  They are interested in how global warming is making changes in the polar ice cap that could affect the amount of water on our planet and cause major changes in coastlines around the world in the future. Looking at these sediments and other changes to the ocean floor can possibly predict, modify, slow down or otherwise prepare what may be to come from these changes.  How do you see what’s below the ice in Antarctica?  -Seismic measurements- Procedures and protocols are always, by necessity, a bit different in the land of the ice, snow and bitter cold that is Antarctica.  The application of seismic technique in the mapping of the Antarctic ocean floor requires similar but special modified seismic equipment.  In this environment, the Thumper truck is a snow cat that pulls a trailer containing the geophones.  The geophones are laid out is a special patter and the Thumper that generates the signal to the ocean floor.   The way it works is that as the thumper hits the ground, in this case the ice, and simultaneously the geophones are triggered to listen for the refractions, calculations are then conducted by computers.  In the warmth of the snow cat, researchers using special software will analyze the response and can see under the Antarctic ice for the structure of the ocean floor.  These seismic measurements allow them to map the research areas ensuring that there are no big rocks below the ice that can hamper accessing their research samples. 

Click on the Thumper picture (Left) for an interesting video and you will see why we say …………………

             Thumper is NOT a Rabbit!



Malehmir, A., Urosevic, M., Bellefleur, G., Juhlin, C., & Milkereit (2012).  ”Seismic methods in mineral exploration and mine planning — Introduction.    

     Geophysicis, 77(5).  Retrieved April 12, 2017.

Exploration Instruments (2017).PEG-40 Accelerated Weight Drop Seismic Source.  Retrieved April 12, 2017.

Nolen-Hoeksema, R. (2014).  A beginners guide to seismic surveying.  Oilfield Review, 26(1).  Retrieved April 12, 2017.

Seg Wiki (2017). Ludger Mintrop. Retrieved April 12, 2017.

US Geological Survey (2014).  A Brief History of the use of sound in ocean exploration:  But first a few facts and definitions.  Retrieved April 10, 2017.


Disneyclips.com (2017).  Thumper.  Retrieved April 10, 2017.

Enjolras, J. (2013). Total pioneers “cable-less 3D seismic surveys in Uganda.  Retrieved April 12, 2017.

National Geographic (2017).  The Ice Thumpers. Continent 7:  Antarctica.  Youtube.com Retrieved April 11, 2017.

Niobrara News (2017) Thumper Truck.  Retrieved April 12, 2017. 

6th Parallel Map & Keywords (2017). Antarctica Map.  Retrieved April 12, 2017.


National Geographic (2017).  The Ice Thumpers. Continent 7:  Antarctica.  Youtube.com Retrieved April 11, 2017.



This week at Hearing International food is king…..Great food is enjoyed in many ways, but there are certain sounds that every good cook hears which will surprise those taste buds from far left field. 

Spiegel (2014) reminds us that smell or scent plays a critical role in how we perceive food and is often confused with aroma. Scent or smell is used to describe a skunk or even perfume, but aroma…describes that special aura of bread, coffee, wine (wine is called the “nose” as well). 

When there is difficulty with smell or scent, there can also be some confusions with taste.  The visual element of food makes the impression of it appetizing and can clearly make or break an otherwise great culinary dish.  Texture is another way people enjoy food from rubbery squid (calamari) to the softness of mushrooms. But it’s sounds from the kitchen that provide the clues as well as the long lasting impressions of….“What’s for dinner?” 


The Sound of Food


The sound of food refers to pan noises or others noises that food makes as its cooked or eaten. These noises can set up delicious memories, such as the noise of mom in the kitchen making that great breakfast or some other noise shich reminds us of great food or drink experiences.  To some, it’s the crack of the spoon on the crème brulee, breaking that brown succulent seal to the crème inside. To others, it’s the sizzle of bacon….heard long before the great smell, or the pour of a beer…. the pop of the can…the whoosh of the cap or cracking that lobster or crab and that shell snapping to let out the goodness.

Nothing is quite like the sound of popcorn popping, heard before the aroma reaches you. The sound sends a message that ”salt is on its way to allow you to enjoy that movie just a little bit more.” Others iconic sounds are  ‘dogs on the grill making that perfect special frying sound, or the “sizzle-whomp” of one of  Kate McDermott’s perfectly baked pies that sets up hunger pains and cravings for dessert. 

About those pie sounds.  It’s the sizzle-whomp of the pie that Ms. McDermott says is the “heartbeat” to a pie.  Kate says that “the sizzle” is the sound of hot butter cooking the flour in the crust melding it into a crisp golden lid and the “whomp” is the sound of the thickened filling bumping against the top crust as it bubbles at a steady pace.” 

Who would ever think that sound has a role in our perception of food? 


The Flavor Sense From the Sound of Food


It’s not only in the sound food makes as it is cooking, but there’s also a flavor sense that is obtained from sound.  The crunch of a chip, the snap of a carrot, or the fizz of a freshly opened beverage may greatly influence just how good we think those foods taste.  Charles Spence is an experimental Psychologist at Somerville College, Oxford, UK who feels that sound is the forgotten flavor sense.   His work on vision and chemical senses asks the question: Do we just smell or taste what we see?   

Spence (2015) headed an Oxford research project to understand the interactions between vision, odor and taste perception and, in particular, to investigate the influence of color, odor and taste on perception as well as the level of processing where any cross modal integration might occur.  In his opinion, a lot can be told about the texture – crispy, crunchy, crackly – just from the mastication sounds heard while biting or chewing.  He feels that there is a growing body of research that shows one can change a person’s experience of what they think they are eating by synchronizing eating sounds with the act of consumption,

According to, “We often think it’s the taste and smell of bacon that consumers find most attractive. Our research proves that texture and the crunching sound is just—if not more—important.”  Texture can reveal how fresh food is as well.  For example, if an apple cracks crisply when it’s bitten into, instead of yielding without a snap, you know that’s a good sign. Even soft foods, like bread, bananas or mousse can make subtle sounds when they’re bitten, sliced or plunged into with a spoon, and Spence believes the commercialization of sounds in the food industry may soon be growing in a big way. 

Science has also shown that changing the sounds a food makes can influence a person’s perception of it.  (probably does not help with Brussel sprouts).  Spence demonstrated that people give carbonated beverages higher ratings when the sound of the bubbles popping becomes louder and more frequent, making sound an indicator for texture and, therefore quality.  

Cooking and food make such sounds that our own Gael Hannan at HHTM reminds us that those without hearing loss can leave the kitchen and wander around the house attending to other chores, still perceiving those wonderful warning signs of food that may be cooking too long, water still running, and other sounds that tell us preparation for dinner is progressing, which those of us with hearing loss do not perceive.  Hannan, our HHTM resident cranky cochlea consumer, says that “there is absolutely no way I’m going to hear a boil gone berserk such as eggs cooking to a molten mass in a pot boiled dry, the water left running in the sink, or that ding-dingity-dinger of something that is done, over done or burnt to a crisp”

The sound of food, cooking or eating is in some opinions more powerful than a super aroma……especially the  sizzle-whomp of a great pie!



Hannan, G. (2012).  Recipes for a good cook with a hearing loss.  Hearing Heath and Technology Matters. Retrieved April 4, 2017.

Moskin, J. (2017).  To become a better cook, sharpen your senses.  New York Times.  Retrieved April 3, 2017.

Spence, C. (2015). Eating with your ears:  Assessing the importance of sound of consumption on our perception and enjoyment of multisensory flavor experiences.  Flavour, 4(3). Biomed Central.  Retrieved April 3, 2017.

Spiegel, A. (2014).  Most satisfying food sounds of all time.  Huffington Post, April 18, 2014.  Retrieved April 3, 2017.