This is an EarthCache and has special requirements for logging it. You cannot log a Found It without responding to the logging requirements set out below.
Only one find claim per Message. Each Geocacher claiming a find must submit an individual response. One team can not lodge a response on behalf of a group of people.
This cache takes its name from both the Highway and the traditional owners of the land.
We would like to acknowledge the traditional owners, the Kamilaroi people.
There aren't many earthcaches around here, so we thought we would add one for those driving this way where you may stop and admire this "out of nowhere" geological feature. It shouldn't take too long to complete, and you may like the chance to stretch your legs, and also learn some local history.
Who leapt from this rock face? Whose graves are near GZ?
Then you can explore the geology and answer the questions below! 
The area in front of you consists of granite rock which cooled from molten magma under the earth's surface about 225 million years ago. Subsequent uplift and erosion have exposed them to the earth's surface. According to geological theory, Gins Leap stands above the surrounding area because it has been more resistant to erosion, probably due to having fewer cracks along which water can penetrate and accelerate the erosion process.
Here's some more geological information about Granite:
It is a common type of felsic (light-coloured mineral) intrusive igneous (basically they cooled below the surface) rock which is granular and phaneritic (you can see it easily) in texture. The word "granite" comes from the Latin granum, a grain, in reference to the coarse-grained structure of such a holocrystalline (completely crystalline) rock. The term 'granite' also applies to a group of intrusive igneous rocks with similar textures and slight variations on composition and origin. These rocks mainly consist of feldspar, quartz, mica, and amphibole minerals. These form interlocking somewhat equigranular matrix of feldspar and quartz with scattered darker biotite mica and amphibole (columnar or fibrous prismatic crystals ) (often hornblende - a dark brown, black, or green mineral) peppering the lighter colour minerals. Granites can be predominantly white, pink, or gray in colour, depending on their mineralogy.
By definition, granite is an igneous rock with at least 20% quartz and up to 65% alkali feldspar by volume. Granite differs from granodiorite in that at least 35% of the feldspar in granite is alkali feldspar as opposed to plagioclase; it is the potassium feldspar that gives many granites a distinctive pink colour. The extrusive igneous rock equivalent of granite is rhyolite.
Granite is nearly always massive (lacking any internal structures), hard and tough, and therefore it has gained widespread use throughout human history, and more recently as a construction stone.
Here's some technical stuff:
The average density of granite is between 2.65 and 2.75 g/cm3, its compressive strength usually lies above 200 MPa, and its viscosity near STP is 3–6 • 1019 Pa·s.Melting temperature is or 1215–1260 °C (2219–2300 °F)
Granite has poor primary permeability but strong secondary permeability. Primary permeability (sometimes called formation permeability ), as discussed above, develops from the original texture of the rock (for example, interconnected pores and vesicles and grain boundaries). In contrast, secondary permeability (sometimes called fracture permeability ) is promoted by rock fracture and foliation, and where it occurs, it is generally the dominant type of permeability. Volcanic rock fracture has numerous origins, such as tectonic movement and proximity to faults, differential compaction that causes stress fractures, cooling contractions, thermal spallation, and eruptive/emplacement brecciation.
Uplift, in geology, is the vertical elevation of the Earth's surface in response to natural causes. Broad, relatively slow and gentle uplift is termed warping, or epeirogeny, in contrast to the more concentrated and severe orogeny, the uplift associated with earthquakes and mountain building.
Granitoid is a general, descriptive field term for lighter-colored, coarse-grained igneous rocks. Petrographic examination is required for identification of specific types of granitoids.
The term "granitic" means granite-like and is applied to granite and rocks of similar composition or texture.
Logging Requirements:
There are just three questions you will need to answer for your smiley.
1. The easy one first: While standing at GZ look up at the rock in the distance, can you tell me the TWO main colours you can see on the rocky outcrop from where you are?
2. And now for something completely different: What kind of Uplift do you think created this outcrop?
3. And finally: What kind of permeability would exist here?
4. And a Post Script: Take of photo of yourself OR your GPS to show a view of GZ. Include it in your message, but please do not post it in your log, it might give too much away.
If possible, please MESSAGE me your answers. I don't deal with email very well. 
Log your find - you will be contacted if there is something really wrong with your answers.
I hope that if you are visiting in Summer, that you have not had to leave your air-conditioned comfort for too long!