[Bass (OP)]

Allen’s Laws of Field Geology

General scientific laws which apply:
1.   The Basic Law (Murphy’s Law): If anything can go wrong, it will go wrong.

2.   Law of Recognition: The more you know, the more you will see.
        a.   First corollary: You see what you are looking for.
        b.   Second corollary: You don’t see anything that you aren’t looking for.

Laws of Field Geology
1.   Law of Complexity: 
        a.   Coat’s First Law:  The geology of an area is always more complicated than you think it is going to be.
        b.   The complexity of the geology is directly proportional to the area that is outcrop.

2.   Law of Accuracy (Callaghan’s Law):  The accuracy of mapping is inversely proportional to the distance from the main roads and the edge of the map.

3.   Laws of Inaccessibility:
        a.   The key outcrops and fossil localities are always found at dark, on the last day of the field season, in the most inaccessible part of the project area.
        b.   When localities must be collected and photographed, they are in the most inaccessible part of the area, or you run out of film.

4.   Law of Efficiency:  The curve of field efficiency is bimodal, peaking at 9:00 a.m., with a smaller peak after lunch, and drops dramatically after 4:00 p.m.

5.   Law of Hand Specimens: 
        a.   The size of the hand specimen is inversely proportional to the square of the distance to the vehicle.  S=K/d²
        b.   The number of specimens collected by the end of the season is inversely proportional to the abundance of the rock type in the area.
        Corollary: The season may end without collecting a single sample of the dominant rock type.

[Don_1]

The loose rock will fall on your head.

[Mazurka]

I would add...

A qualification to 2:  Accuracy can of mapping can also locally affected by the forraging potential of an area - plenty of wild mushrooms or berries will reduce the accuracy of mapping by a remarkable extent

3.C The photograph(s) of the key exposure will be slightly blurred or unavoidably have the shadow of the photographer across the middle of them

5.C The specimen rejected (for reasons of size, excess weathering  etc.) will be the key to understanding the area

6.A All electronic instruments or other recording equipment have battery packs incompatible with all other instruments
6.B All battery packs have a life somewhere between 33 and 50% of the manufacturers stated capacity
6.C The point when the battery packs fail is
i) geographically as far from base as possible
ii) in the middle of a critical measurement

Special rules for Environmental Geology / site remediation field work
7 Portable Gas Analysers
7.A When taking gas readings from boreholes portable gas analysers will draw water into themselves on the second to last borehole on site.
7.B The spare in line filters stored in a pouch of the carry case prevent water damaging the gas analyser will be damp/ used when 7A has occurred
7.C The calibration certificate for the instrument will expire a week before an interested third party (boss/ client / environmental regulator) accompanies the technician monitoring the boreholes

8.A The week set aside for trial pitting will be subject to extreme rainfall (or other weather event) that somehow jeopardises the operatives/ plant
8.B The sections of well casing due to be installed in boreholes will have an incompatible thread pattern
8.C When unloading supplies (like bags of bentonite or pipework/ fittings) if the weight of supplies exceeds 1 tonne, there will be no plant available to help unload before the delivery driver needs to leave site so it all has unloaded manually.
8.D Plant will become available 5 minutes after the last bag has been unloaded(see 8.C)

[Ophiolite]

There are two important conditions that afflict the field geologist when he seeks to identify the rock type in a specific series of outcrops. These are The Differential Dilemma and The Similarity Syndrome.

In the first every specimen looks different, even though they are of exactly the same rock type. In the second every specimen looks the same, even though they are totally different.

These two effects caused me to take up engineering.

[Geezer]

Law of Recovery

The probability of recovering lost car keys is inversely proportional to the square of the distance from the nearest working telephone.

[JimBob]

1.) If you decide to core a well, the point at which the core point is reached is about 1 PM in the afternoon on a nice day. If you pull the core, it will be between 2 and 4 AM, cold weather will have moved in, it will be well below freezing, raining and the core will have been pulled "wet," i.e., there will be drilling mud gushing out of it as you stand at the bottom of the core barrel trying to catch the pieces of the core and keep the core oriented correctly;

2.) If you lick a core to see if it has salt water or hydrocarbons in the pore space, it will always have hydrogen sulfide in the oil, gas or salt water. You thus end up with a very bad taste in your mouth.

3.) When putting sand grains between the tongue and teeth to better judge the grain size of the sand, the sand is invariable collected from the only place on the outcrop where someone has left a small shard of glass and includes the same. This rule applies even if one is 100 miles from a paved road.

4.) While crossing a creek, even the most shallow one, you will slip, fall and get soaking wet with greater frequency the lower the temperature is.

Others to follow after the turkey settles.

[Mazurka]

Ahh, a man after my own heart.  If god had not meant geologists to lick rocks he would not have given us tongues [:0] [:I] [xx(]...

[Don_1]

3.) When putting sand grains between the tongue and teeth to better judge the grain size of the sand, the sand is invariable collected from the only place on the outcrop where someone has left a small shard of glass, or allowed their dog to do a crap and includes the same. This rule applies even if one is 100 miles from a paved road.