Thread by @CriticalStress_

Long Thread:

Geology is an utter mystery to many, largely because geologists insist on using a ridiculous amount of terminology.

It’s time to Demystify Structural Geology!

Presenting new, simplified & realistic terminology to bring Structural Geology to all!

#DemystifyGeology

Structural Geos just love big fancy words, like ‘fault’ & ‘fold’, mostly because we think they make us sound cooler at the few parties we get invited to.

But how can others possibly hope to ever understand such complicated terms?

Fear not! This will never be a problem again!

Presenting the ‘Structural Geology Demystified’ Classification scheme!

I’ll explain it in more detail and you’ll see how much simpler it is to use.

Please feel free to add your own examples with the new terms or even demystify your own science!

First, what us snooty structural types call 'faults' & 'fractures'.

Really? ‘Fault’ is such a negative word. Lets call ‘em what they are – breaks in the rock.

Faults show movement, so they are ‘slidey-breaky’s’.

Fracs don’t, so they are ‘cracky-breaky’s’

There are three main types of slidey-breaky’s. Pully-tuggy, Pushy-Shovey and Sidey-Waysy.

They each have associated squeezy regimes, depending on if the up-down squeezy is the big, little or middle squeezy respectively.

Slidey-breaky’s and cracky-creaky’s are both types of snap-crackle-pop structures, which form when rocks have either low squigyness and/or they breaky under fast squeezy squashy.

Here’s an example of a pully-tuggy slidey-breaky in outcrop from Miri, Malaysia. Pully-tuggy slidey-breaky’s are common in sedimentary basins, such as this example seen on seismic, offshore Brunei.

Teeny-tiny pully-tuggy slidey-breaky’s in sands & coals in the Jerudong Upsy-Downy, Brunei

Pully-tuggy slidey-breaky’s are particularly common in places where the Earth’s crust is being yanked apart, called ‘mega-rock-ripping’ zones, like in the East Africa Mega-Rock-Ripping Zone.

Pushy-shovey slidey-breaky’s occur when there are flat-wards squeezy is bigger than the up-down squeezy. Here are lots of little stacked pushy-shovey slidey-breaky’s (Bristol Channel, UK).

Sidey-waysy slidey-breakys form when the up-down squeezy is the middle squeezy.

These are the most boring type of slidey-breaky, no matter what some structural geos or seismologists may say. So, let's not speak of these again.

The other main type of structure are wiggly-waveys. These are blobby-wobbly structures that form when there is slow squeezy-squashy and/or when rocks have low squidgyness.

Example of small wiggly-waveys of sparkly-crystal-flatsy's in Second Valley, South Australia.

The Demystifying Structural Geology nomenclature simply defines wiggly-waveys by how they look from left to right. So, we have upsy-downys and down-upsys and wiggly-waveys that are neither upsy-downy nor downy-upsy.

Wiggly-waveys have several parts. We call the bit in the middle the ‘middle-bit’ and the bits to the sides are called the ‘side-bits’. The intersection of the middle-bit and the stripy-flatsy (or sparkly-crystal-flatsy) is called the middle-bit line.

Wiggly-waveys are also described by their amount of wiggly-waveyness, which range from barely, to kinda, to nicely, to proper, to speccy, and even wows.

Here are some lovely proper-speccy wiggly-wavey’s that formed in the Hercynian mega squishy-squshy time (Morocco).

Proper upsy-downy and downy-upsy wiggly-waveys. Note these wiggly-waveys are not quite up-down, but have middle bits with a ~60 degree leftwards least flatness direction. Greater Caucasus, Azerbaijan

Here is a nicely upsy-downy wiggly-wavey in Thailand. Notice the great example of stripey-flatsy slidey-breaky on the left (upsy) side-bit that is offseting a basalt dyke.

A proper downy-upsy wiggly-wavey associated with a pushy-shovey slidey-breaky (Bristol Channel, UK). Note the kinda upsy-downy wiggly-wavey with a northwards least flatness-direction middle-bit (left).

Here are the classic neither upsy-downy nor downy-upsy crinkly wiggly-waveys in Milbrook Haven, UK.

Neither upsy-downy nor downy-upsy nicely crinkly wiggly-waveys with clear flaky-breaky through the middle-bits. Bristol Channel, UK

Here is a great example of how squishyness controls wiggly-waveyness. The low squishyness stripey-flatsy form kinda wiggly-waveys, or even show snap-crackle-pop features. The high squishyness stripes-flatsy form proper, speccy and even wowza wiggly-waveys. Example from UK.

Okay. Now you should be getting the hang of structural geology! But first, a few more examples.

Here is a heaps big muddy cracky-breaky in the Jerudong Upsy-Downy, Brunei.

Pushy-shovey slidey-breakys with a kinda neither upsy-downy nor downy-upsy wiggly-wavey in Svalbard. These form in a pushy-shovey squeezy setting with the big flat squeezy from the left and right.

A crazy mess of mostly neither upsy-downy nor downy-upsy nicely-proper crinkly wiggly-waveys associated with pushy-shovey cracky-slidey in the Khao Khwang wiggly-wavey-pushy-shovey belt, Thailand.

Okay, now its time to test yourself! Describe the features you see in this outcrop in Thailand!

For a real challenge, you can try describing these structures from Svalbard (photo courtesy Simon Lang). Lots of wiggly-waveys related to slidey-breaky.

Okay, that's enough #DemystifyingGeology for now. I'm sure you'll agree that this new nomenclature scheme is much easier to use and simpler to understand.

Please feel free to add and describe your own photos, or even demystify something else, like volcanology or sedimentology!