Editing 40d:Exploratory mining

{{quality|Masterwork|16:16, 29 April 2011 (UTC)}}{{av}}

Exploratory mining is the process of mining large areas in order to locate resources such as [[gem]]s, [[metal]] [[ore]]s and other types of [[stone|rock]]. It is also used, to a lesser extent, to find the locations of hidden underground features such as [[chasm]]s, [[underground river]]s, [[magma]] and [[adamantine]].

The [[cheating]] counterpart to exploratory mining is the infamous [[utilities#reveal.exe|reveal]] tool.

To know how you should dig, it helps to know what you are looking for. When a  second material appears in a [[layer]], depending on the type of stone, ore or gem it appears in one of three shapes, large clusters, small clusters, or veins.

(For a more complete discussion of this, see [[Vein|veins and clusters]])

* '''Large cluster''': An oval that occupies nearly half of a 48x48 block, area-wise. Only one appears per block.  (The stones that comprise large clusters ''tend'' not to have small clusters or useful veins - see specific [[stone]] type for details.)

It's recommended to first dig out a wide grid of single shafts that hit the centers of the major (48x48) [[area block]]s - if your map is 6x6, that's 36 center-shafts (or as many area blocks as you care about to start with).  With a few exceptions*, if a block has a large cluster it will ''not'' have any other veins or small clusters within it - nothing.  So, depending on the stone found, blocks with large clusters can be skipped right away because they are mostly worthless.  (Note that layers above or below are not influenced by each other - this may influence whether you use shafts or tunnels for your exploration.)  Area blocks without a large cluster can be explored using one of the patterns mentioned below. This will save you a lot of additional work (and dug out generic stone).

:''(* Exceptions include [[adamantine]] veins, which can occur in any layer or large cluster in their block; [[olivine]] clusters and [[chromite]] veins, which can contain [[demantoid]]s and [[native platinum]]; and [[magnetite]] with its possible [[platinum]] veins; <small>...and possibly others?</small>)''

Some players may wish to first identify the layers beneath the surface of their map.  If (as described immediately above) you dig exploratory shafts that hit the centers of the major (48x48) [[area block]]s, you will hit many [[cluster|large clusters]] that give you no helpful information - for instance, many stone found in clusters are found in "any layer". The solution is to dig nearer the corners or edges, to avoid the 20x40 oval that is always close to the center of the block.  However, remember that the game does make the borders between [[area block]]s fuzzy - so the closer you get to that border, the less reliable your information.   

Often a player will have need of a specific type of metal - and that requires that you either [[trade]] for it, or find a vein of an appropriate ore.  Now, it's quite possible that that necessary ore is simply not present on your map - it's rare that a map will contain ''every'' ore.  But ''if'' it's there, it's usually not too hard to find, if you know where to look.

In short, ore comes in veins, which tend to be a few tile wide and very long (maybe 20-40 tiles?) and snake randomly across a layer, so you don't need to expose every tile to find them, far from it.  The trick is to know where to start looking, and for that you need to identify the stone layers present on your map. First, use the two techniques described above - with the second, you're trying to see what [[layer]] stones are available to search, and with the first you're trying to see which of those layers can be skipped.   

Then go to the wiki article for the specific [[metal]] you are seeking - maybe [[iron]], maybe [[copper]] or [[zinc]], whatever.  There you will see, in the side-bar, what [[ore]](s) will produce that metal.  ([[Alloy]]s may take one additional step, to find all the necessary metals to make that alloy, but the process is the same.)  It's quite possible that more than one ore will produce the metal you want.  Then read up on the ore(s), and see what layers it's found in.  Compare that to the layers you have found on your map - where they are the same, that's where to look.   

::[[Iron]] has 3 ores: [[hematite]], [[limonite]], and [[magnetite]].  Looking at those articles, we find that magnetite is easy - it's a [[large cluster]] (about 20x40!), centered in an area block of [[sedimentary]] layer stone - check that article to see what kinds of stone layers are "sedimentary".  If you have area blocks of sedimentary layers, center-punch a single shafts down through them and see.  Limonite is also found in sedimentary, but in veins - this will take some exploration through the entire layer, but because we are looking for veins we don't have to reveal everything, not even close.  Hematite is found in sedimentary as well, but also in [[Igneous extrusive]] layers - so that's another category of stone to check.   

Not all layers contain ''every'' ore they might contain, but ''if'' they do, that's where you'll find it.  If you have none of the necessary layers, there is ''no chance'' you will find veins of that ore.  You don't find iron ore in [[metamorphic]] layers unless it's extending from a different, nearby type - it just isn't there, period.  If you want even ''a chance'' for a specific type of ore, make sure the proper ore-bearing layer stone is present on your [[embark]] map!

(This general approach is also used to determine "where to mine next?", even if you ''aren't'' looking for anything specific.  Knowing that [[granite]] or [[gabbro]] has a better chance to pay off better than [[diorite]], and not to bother with the blocks with large clusters, gets your miners to the motherload that much faster.)

If all this is a bit overwhelming, and/or you have layers that seem "completely useless" - well, you might be right (on both counts), but [[The Non-Dwarf's Guide to Rock]] can be helpful in getting your feet back under you.  It's useful to know what might be found where, and when nothing will ever be found somewhere.

''Target'' refers to the [[vein|size and shape]] of what you are hoping to find, the target material present in the rock layer as it typically appears - individual tiles, small clusters, veins, large features, whatever. It's theoretically represented by the fraction of desired material in the soil layer, but one can seldom state it accurately or even estimate it.  "Target" is determined by the specific type of materials you're after - for the classification of the specific target material you are hoping to find, see the [[gem]] and [[stone]] articles.  Single tiles are obviously the smallest target, followed by small clusters (at a maximum size of 3x3), veins (typically a sinuous line approximately 3 wide x 30-40 long) and large clusters (a rough oval about 20x40 centered in the [[area block]]). Underground features such as [[Vent#Magma_sources|magma vents]] or [[lake|underground pools]] have about the same target size as large clusters.  

"Target" and "visibility" (below) are directly related. If you are after the precious gems: diamond, sapphire and ruby, you will see that these can be found only in [[kimberlite]] (diamonds) and [[bauxite]] (sapphires and rubies) respectively. So you only need to use one of the lower-visibility methods to find the veins of kimberlite in a [[gabbro]] layer or the large clusters of bauxite in [[sedimentary layer]]s respectively, and then dig those out using one of the patterns that reveals every tile.

To better understand this, see [[vein|veins and clusters]].

''Re-usability'' is represented by the largest room size achievable by digging into the solid rock left behind without rebuilding any walls or floors.  Exploratory mining typically leaves behind a monotonous, repetitive underground landscape of shafts or tunnels. The excavated level may be hard to reuse for habitation, storage or industry without additional digging and significant rebuilding efforts that leave behind inferior walls that cannot be engraved. Re-usability is subjective, and it depends on the desired layout. Re-usability is a priority for a small [[embark]] site or a sprawling fortress.

* ''Bottom line'': Easy to designate, and a single miner will focus on one tunnel to the end or they take a [[break]]. This method achieves the same visibility as hollowing out, but using a mere third of the labor. Ideal for hunting single-tile gems. As an added bonus, it is more efficient than a 3&times;3 design.

* ''Bottom line'': This method is 2nd most efficient of those with 100% visibility. This one doesn't use other levels to move from one spot to another but is annoying to designate. Alternatively, you can use this [[User:LockeslyLCrit/DiagonalMining.ahk|script]] for [[40d:Utilities##AutoHotKey|AHK]] to mine four diagonal shafts of 140 squares long, saving you some annoyance.

:It takes a lot of keypressing to designate, although you can save some effort by designating every third row (as in the rows method, except with stairways) and then removing the designations ({k|d}-{k|x}) on all but every third column.  Alternately, [[User:StrawberryBunny/Mineshaft.ahk|here]] is a ahk script to save your fingers.  For a discussion on optimizing travel times through mineshafts, see [[mineshaft stitching]].

The pattern as shown is 1 up-ramp every 7 tiles vertically, or 1/14 horizontally, though this could be turned 90 degrees.  The downramps are shown, but are only designated on the next level down.  (Be ''sure'' you know how [[ramp]]s work before trying this one!)

* ''Reusability'': Moderate.  3x3 spaces cannot be created until at least one up-ramp is removed or a down-ramp floored over.  [[Ramp]]s are less convenient than stairs for many purposes (for example, digging out the wrong tiles around a ramp can make it unusable).   

Underground features are a lot larger than [[vein]]s and [[cluster|small clusters]], so the 15x15 block method is more than sufficient to find them. If you dig tunnels rather than shafts, you only need to dig every 3rd [[z-level]] out as even the shortest feature, a [[cave river]], can be discovered on any one of the 3 levels it influences with "warm" or "damp" stone, as shown in the side profiles below.

Once you encounter warm or damp stone you want to back off a couple of squares and dig an up [[staircase]]. On this new z-level dig another tunnel to where you just found damp/warm stone. Depending on how tall the feature was and whereabouts you hit it, you may need to repeat this approach. Eventually your miner will reach a z-level where he can safely dig all the way through to the "surface" of the feature. '''Be careful! Your miners will happily dig ''up'' into a magma pit or lake, and burn or drown themselves, with no warning!'''

Sometimes a magma pipe will not reach the surface, stopping one or more [[z-level]]s below what is immediately visible. In these cases it will have an "'''obsidian cap'''" over it, which is easier to find: just search for any hills or mountainsides that have a circular chunk missing and/or a grey circle of stone (example on the right).  Another clue will be a (semi-)circular rise in elevation (which may nor may not be of [[obsidian]]) with no [[ramp|slopes/ramps]].

Digging a single shaft of [[stairs|up/down stairs]] down near the middle of an obsidian cap will soon (and safely) reveal the [[magma vent]].  You can safely designate this shaft as deeply as you want - when your miners hit the vent the game will pause, you will get an [[announcement]], the next shaft-designation will be canceled and they will stop that particular task.