PhD Diary - Exploration Geophysics

Let's first discuss how to spell antennae . Thanks to the proliferation of American literature and media in Australia, we have ended up with this hybridised language where sometimes it matters which way the word is spelled, and sometimes it doesn't. Antennae qualifies as a 'doesn't'. In the US and Canada, antenna is a singular, while antennae refers to a plural. At least, it does when referring to insect antennae. Metallic antennas, like are used practically everywhere, are antennae or antennas, depending on your own preference. To the point however, what actually defines an antennae? 'Antennae' refers to an object which transmits or receives electromagnetic radiation. It 'radiates' this energy thanks to a few fundamental laws of physics. As you may well know, most things have a 'charge' associated with them. This is generally due to a lack, or surplus, of charged particles of either polarity (i.e. positive or negative). When ...

What IS the Laplace equation? Whenever researching mathematics, there almost never seems to be a simple explanation of what the function actually does. Usually, this is because a function will convert one abstract notion of a small branch of mathematics into another abstract notion of a small branch of mathematics. It means absolutely nothing for the average person. To begin, lets breakdown the Wikipedia page. This is usually my default go-to, as it's written by people, not robots (usually). In mathematics, Laplace's equation is a second-order partial differential equation named after Pierre-Simon Laplace who first studied its properties. Great. I'm still none the wiser. This is often written as Δφ = 0  or   ∇ 2 φ = 0 Okay, Now we're getting somewhere. Luckily for me, I have a vague idea what the Laplacian operator, or  ∇ 2 , actually refers to. I hear you saying;  " wow, it's really that simple - all it does is relate the divergence of the ra...

'Cation exchange capacity' (CEC), is a term that gets thrown around when discussing the electrical properties of clays, but what does it actually mean? The literal definition is:  "...the number of exchangeable cations per-dry-weight that a soil is capable of holding, and available for exchange with the soil water solution." What does this actually mean? Going right back to basics, charges can be divided in anions (an-eye-ən) and cations (kat-eye-ən), representing negative and positively charged ions , or ' non-equally charged atom or molecule ', respectively. A high cation-exchange-capacity therefore means there is a large number of positively charged, mobile ions available to 'exchange' with other ions. What about the physical values? Soil colloid — CEC meq/100 g Sesquioxides — 0–3 Kaolinite — 3–15 Illite — 25–40 Montmorillonite — 60–100 Vermiculite — 80–150 Humus — 100–300 Table from Wikipedia (https://en.wikipedia.org/wiki/Ca...

I bought a car. It's a Mitsubishi Lancer CJ ES Sport 2014 model, and features a continuously variable transmission (CVT) drive train. The CVT is quite interesting. Very simple in theory. CVT makes for optimal tuning between the smaller pulley piston, reducing flow amount of oil pump, and the direct control torque converter by which an efficient engine output transfer and a smooth ride are realized. Based on accelerator travel information from actual drivers under actual driving conditions, the system controls to obtain the driving force in accordance with the driving situation, at the optimal efficiency point of the engine and the CVT. This enables a supple and smooth driving feel under all driving conditions while also achieving low fuel consumption. Sounds like nonsense and advertising spin. This picture explains it much better. The gear ratio is adjusted via continuously increasing or decreasing the radius of the gear to maintain the most efficient power deliv...

La Nina and El Nino events are not actually related to Perth. To be more specific (or should I say, 'Pa-cific'), they're associated with the cooling or heating of the Pacific ocean surface temperature, where the result is an increase or decrease in the convection cell driving localised rainfall. The differential temperatures strongly affects the location and amount of rainfall (amongst other things) found at the increasing gradient of the cell. The Bureau of Meteorology has a nice picture describing the phenomenon, The dominant weather pattern affecting Perth's climate is the 'West Trough', and to a lesser extent, the 'Indian Ocean Dipole'. In fact, there are a vast number of weather patterns which all affect Perth, to some extent. The recent weather is highly erratic, breaking the record for coolest January, and 6th wettest on record.  A combination of tropical lows, and a shift in the sub-tropical ridge are generally believed t...