The purpose of scientific research is to increase the knowledge of all interested humans, and thus research is wasted effort if it is not communicated clearly. The following is not a substitute for a course in scientific writing, but it compiles one writer's comments relevant to scientific writing and to problems often seen in text produced by geology students and geologists.
(E1) Edit, and edit, and edit. We're all taught to write, and so we can put words together as sentences and sentences together as paragraphs. Less often are we taught to look at the sentences we've written, to find their flaws, and to rewrite them. Even less often are we taught to restructure our paragraphs to maintain a flow of thought. Still less often are we taught to move whole paragraphs around to better organize our entire opus. However, all this is critical to good writing.
Editing requires time (i.e., time budgeted before a writing assignment is due) and it requires a skeptical reading, in which one assumes that one's writing can be improved. If you read your work while thinking "this is good stuff; I'm just looking for a few problems", you won't find many problems. If you read your work while thinking that you are certain that there are problems, you will find more of them, and the product will be improved. As a result, other scientists will understand your work better.
And then proof-read. Editing and proof-reading are two different things. The former is an ongoing attempt to improve a manuscript by rewriting; the latter is a final check for mistakes of spelling, grammar, and fact.
(E2) Let the subjects do the work in your sentences. If you do, you'll have shorter sentences that will be clearer and more direct. Consider the following examples:
(i) "It can be seen from the ICP data that . . ."
vs. "The ICP data show that . . ."
(ii) "Due to the scarcity of outcrops, the extent of the alteration cannot be determined precisely"
vs. "The scarcity of outcrops prevents precise determination of the extent of the alteration.
(iii) "From the trace element data follows an interpretation . . .",
vs. "The trace element data show . . .",
(iv) "The fact that the turbidites are folded means that . . ."
vs. "The folds in the turbidites indicate that . . .",
(v) "A major episode of contact metamorphism is suggested by the hornfels facies . . . "
vs. "The presence of the hornfels facies suggests . . .".
(vi) "In a study by NOAA, it was discovered that . . ."
vs. "A study by NOAA discovered that . . ."
(vii) "By looking at satellite images you can see . . ."
vs. "Satellite images show . . ."
(viii) "Based on these results, it appears that . . ."
vs. "These results suggest that . . ."
(ix) "Dolomite shows an apparent increase updip based on the relative heights of the dolomite and calcite 1014 peaks."
vs. "The relative heights of the dolomite and calcite 1014 peaks indicate that abundance of dolomite increases updip."
(x) "At Locality 23, it was observed that brachiopods are common."
vs. "Brachiopods are common at Locality 23."
(xi) "An increase in abundance of MgO is noticed going up the section."
vs. "MgO increases in abundance upwards through the section."
(xii) "Under cathodoluminescence the dolomite exhibits a bright orange."
vs. "The dolomite cathodoluminesces bright orange."
(xiii) "It would be more effective to calibrate the spectrometers before analyzing the samples."
vs. "Calibration of the spectrometers prior to analyzing the samples would be more effective."
(xiv) "Comparing the older basalts with the Holocene ones shows that the older ones have more Mg."
vs. "The older basalts have more Mg than the Holocene ones."
The second sentence in each pair is much clearer and more direct. Note that each uses the conceptual or physical agent of the sentence as the grammatical subject of the sentence. As you edit, examine each sentence to see what its subject and predicate are doing in the sentence.
The examples above also show that any sentence beginning with or containing "It can be . . .", "It would be . . .", "The fact that . . .", "Based on . . .", or other functionless words can be rewritten to be more effective.
(E3) Choose your inferential words carefully. Experienced scientific writers have a mental toolkit of phrases to characterize how their evidence relates to possible conclusions. For example, we can say that a piece or body of evidence " is compatible with" or "suggests" or "indicates" or "shows" or "proves" an idea. This list is in rough order of degree of certainty:
"Are compatible with" or "are consistent with" means that our data are compatible with more than one interpretation, but at least they're compatible with the interpretation at issue.
"Suggest" means that our data support the interpretation at issue more than they support other interpretations, but we're far from certain about that interpretation.
"Indicate", "show", and "demonstrate" represent a higher level of certainty, in that hardly any other interpretation could account for the data.
"Prove" means that there is absolutely no possibility that any other interpretation could be correct. Most scientists never use the word "prove" in their writing.
(E4) Link sentences and paragraphs together so that the continuity of your ideas is apparent. Consider the following paragraph:
"Some flattened contacts in these rocks may be the result of either mechanical or chemical compaction, but many of the concavo-convex contacts and all the sutured contacts are indicative of intergranular pressure dissolution. At the sutured contacts, laminae are terminated by intergranular sutures, indicating that cortex has been removed rather than plastically deformed (Figs. 3b,c,d). This removal of laminae without bending demonstrates that the grains were solid at the time of intergranular compaction, and that laminae were dissolved, rather than displaced. One might argue that cerebroid ooids could fit together so as to yield seemingly sutured contacts without pressure dissolution, but the interpenetration of otherwise round ooids (Figs. 3 b,d) shows that this cannot explain all the sutured contacts. Round quartz grains pushed into ooid cortices (Fig. 3a) similarly defy explanation as accidents of interfitting grains. Pressure dissolution thus seems to be the only reasonable explanation of the fabrics observed.Note that the italicized words link ideas and thus link sentences in this example. If one removes all the italicized words (and splits single sentences into two sentences where there are "buts"), the text becomes a collection of unconnected thoughts.
Larger-scale evidence of pressure dissolution in these limestones includes . . ."
(E5) Explicitly define terms when needed. You may use terms in a specific way that requires you to define them explicitly, and defining them may be a service both to yourself and to your readers. For example, in writing about stalagmites, it's easy to use "layer" and "lamina" and perhaps even "horizon" interchangeably (not wise), and to use "couplet" to talk about a pair of layers (o.k.), and then to use "layer" where one means "couplet" (not good at all). The reader is quickly confused, and in fact the writer may get confused too. Explcit definition and subsequent consistency are much better.
The caveat that must follow this advice is that one shouldn't redefine terms that already have standard meanings in the literature. If a writer announces that he or she will henceforth use "ooid" to refer to multicrystalline quartz grains, he or she isn't doing anyone any favors. The advice above best fits in characterizing things or processes about which no one else has erected terminology, or things or processes so easily decribed with non-technical terms (like the "layers" above) that such terms are easily used but easily misunderstood.
(E6a) Be careful with your tenses. Because geology is so historical and/or interpretative, geologists have to talk about the evidence that presently exists for past events. The present tense is used to talk about things that still exist, whereas the past tense is used to talk about things that no longer exist or that happened in the past. For example:
The deepest facies is characterized by a high diversity of fossils but low abundance of fossils. This facies was probably deposited . . . .or
The pore-filling cements in these limestones are ferroan calcites and dolomites, suggesting that fluids moving through these rocks late in their history were depleted in oxygen and . . . .The deepest facies and the pore-filling cements still exist, so they belong in the present tense. The deposition of that facies took place in the past, and the fluids from which the cements were precipitated existed in the past, so both should be in past tense.
(E6a-i)Problems with tenses also commonly arise in citing previous work. If something has been published, it was written in the past and thus is reasonably treated in the past tense. However, the authors may have made conclusions about materials or processes that continue today and thus should be characterized in the present tense. Thus the most reasonable usage might be
Porter and Al-Tabakh (1978) reported that the dolomites exposed on Mt. Morrison are rich in Zn and Cu. (They reported in 1978 a characterization that presumably still exists today.)However, if a paper describes specific actions or experiments that happened in the past, the past tense is appropriate. For example,
Brezinzki and Smith (1974) reported experiments in which the melting temperature of MnO was 2049 K (They reported in 1974 a result that happened in the early 1970s.).
(E6b) Don't confuse real things with inferences. For example, geologists often talk about facies, which are bodies of rock with uniform characteristics. They try to make inferences about those facies, and often they infer that certain depositional or diagenetic facies were deposited in or affected by certain depositional or diagenetic environments. Problems arise when the two are confused. For example,
"The organic-rich mudstone facies in this section is overlain by a subtidal environment"leads to a confusing image. It would make more sense to say
"The organic-rich mudstone facies in this section is overlain by a series of fossiliferous packstones and grainstones."In each case, rocks are now overlain by rocks, whether we identify them lithologically (as in the first example), or by our inferences about them (as in the third example), or even by a combination of the two (as in the second example).
or "The organic-rich mudstone facies in this section is overlain by strata deposited in a subtidal environment."
or "The deepwater sediments in this section are overlain by packstones and grainstones deposited in a subtidal environment."
(E7) Be clear but tactful in comparing your findings to previous data and interpretations.
There seem to be at least three ways that you can write with regard to other people's conclusions that now seem to be incorrect in light of your work.
1. You can barely mention those other people, or mention them with little comment, and never point out that your results are incompatible with their conclusions.Type 1 is ineffective because it doesn't tell readers why your results are significant, and so your work doesn't achieve its full meaning. Type 3 engenders ill will, which will do you no good in the future, and it makes you seem pedantic. Type 2 is best, because it states what seems to be the truth (your data show someone's previous ideas to be incorrect) but puts the blame for embarassing that someone on the data, rather than on you.
2. You can mention those other people and their work, and say that your results "fail to support" or "are incompatible with" their conclusions.
3. You can identify those other people and their work, and say that your results show that their conlusions are flat-out wrong, and silly, and the result of shoddy work and weak thinking.
(E9) Use "which" and "that" correctly. "Which" follows commas and introduces modifying but inessential clauses. "That" does not follow commas and introduces clauses that are essential to identifying the antecedent. For example:
"He took the box that was on the top shelf."
"He took the box, which was on the top shelf."
The first sentence implies that there was more than one box, and he took one of them. Thus the clause is necessary to identify the particular box. The second sentence implies that there was only one box to begin with, and the clause just provides extra information.
Consider how the geological (and, in the second case, humorous) implications of these sentences change:
"All basalts that are vesicular may potentially become amygdaloidal."
"All basalts, which are vesicular, may potentially become amygdaloidal."
"We also report X-ray diffraction analyses, which confirmed our hypotheses."
"We also report X-ray diffraction analyses that confirmed our hypotheses."
In the first pair, the second sentence is geological untrue. In the second pair, the second sentence might be a sad comment on how some people do science.
(E10) Beware of unintentional geological puns, both because they are distracting and because they can sometimes cause real confusion. Some favorites include
The factors that shape sand compositions include . . .
One of the elements controlling the chemical compositions of granites is . . .
This process caused a reduction of d13C . . .
Earthquakes rocked the Loma Linda area in . . .
The speleothem's calcite layers are a record of precipitation . . . (rainfall, or chemical precipitation of calcite?)
(E11) Beware of strings of nouns, because they make traps into which many scientific writers fall.
Snail shell destruction in perireefal environments is . . .
Does this mean "Destruction of shells of snails . . ." or "Destruction of shells by snails . . ."?
Skarn mineral zonation is . . .
Does this mean "Zonation of (different) minerals in skarns . . ." or "(Chemical) zonation within minerals in skarns . . ."?
The northern fault exposure is . . .
Does this mean "The northern of two exposures of one fault. . ." or "The exposure of the northern of two faults . . ."?
A favorite non-geological example is a street sign along US 27 in Oxford, Ohio, warning of a "Heavy Pedestrian Zone".
(E12) Avoid the common grammatical mistakes. Different people forget different rules, but some of the most commonly overlooked grammatical tidbits are the following:
(i) "Data" is a plural word; its singular is "datum". "Criteria" is a plural word; its singular is "criterion". "Phenomena" is a plural word; its singular is "phenomenon".
(ii) "It's" is the contraction of "it is", whereas "its" is the possessive of "it".
(iii) "However" is not a conjunction, but in the 1990's its use as one abounded. The following are grammatically acceptable:
"The surface was eroded, but it was not subaerially exposed."
"The surface was eroded; however, it was not subaerially exposed."
"The surface was eroded. However, it was not subaerially exposed."
However, the following is not acceptable:
"The surface was eroded, however it was not subaerially exposed."
Some authors will insist that "However" should never appear at the beginning of a sentence. However, that restriction has never made much sense to me.
(iv) Commas separate two independent clauses, each of which have a subject and a verb. Consider the following sentences, all of which contain that same strings of words:
1. "The cat ate the blackbird and the robin and the starling ate worms."
2. The cat ate the blackbird and the robin, and the starling ate worms."
3. The cat ate the blackbird, and the robin and the starling ate worms."
In Sentence 1, the fate of the robin is unclear, whereas in Sentence 2 the robin was eaten, and in Sentence 3 the robin happily ate worms. The existence of the comma is critical to our knowing what this string of words means.
(vi) "Overlie" is the verb to express superposition of one stratum over another, whereas "overly" is an adverb meaning "excessively".
(E13) Don't confuse words for time and logic.
(i) "While" is commonly used for "although", "but", or "whereas". "While" is a term for time; "although", "but", and "whereas" are terms for logic.
"The Ascot Member was deposited subaerially, while the Derby Member was deposited under subaqueous conditions."
Does this mean "The Ascot Member was deposited subaerially during the time that the Derby Member was deposited", or "The Ascot Member was deposited subaerially but the [perhaps older, perhaps younger] Derby Member was deposited under subaqueous conditions"?
(ii) "Since" is commonly used for "because", but "since" is a term for time and "because" is a term for logic. Consider the non-trivial potential for confusion:
"Since the moraine was deposited in the Illinoisan, it has been intensely modified by stream erosion".
Does this mean "Since the time the moraine was deposited . . " or "Because the moraine was deposited in the Illinoisan . . ."?
(iii) "Subsequently" is a term for time, and "consequently" is a term for logic:
"Jones (1998) showed that NaBr affects polyp growth, and subsequently Ekatabo (2000) studied the effect of NaBr on byrozoan zooids".
Does this mean Ekatabo did her work because Jones did hers, or simply that Ekatabo did her work after Jones did hers?
(iv) "As" is a word for time, whereas "because" is a term for logic. Consider these examples:
"As the ice mass had melted, the land surface rebounded."
Does this mean "The land surface rebounded because the ice mass melted" (it might to a Brit), or "The land surface rebounded at the same time as the ice mass melted" (which might be wrongly inferred by most Americans)?
"As the sand was deposited in a rapidly subsiding basin, it underwent pressure dissolution."
Does this mean "The sand underwent pressure dissolution because it was deposited in a rapidly subsiding basin" (it might to a Brit), or "The sand underwent pressure dissolution at the same time that it was deposited in a rapidly subsiding basin" (which might be wrongly inferred by most Americans)?
(E14) If you want to write well, Don't confuse words for magnitude and elevation.
It's quite common to use "high" to mean "large" or "great", and likewise to use "low" to mean "small". Such usage can nonetheless lead to confusion. Consider these examples:
"The higher δ13C values in this stratigraphic section indicate . . ."
Does this refer to the largest δ13C values, or to the values measured from samples higher in the section?
"The lowest depths in the Blankedyblank Basin are found . . ."
Does this mean the least depth, or the depth at lowest point in the basin?
"Blankedyyblankedyoids live in a variety of water depths (up to 5000 meters) ."
Does this mean "up from trench-like depths to 5000 meters", or "from shallow waters to depths as numerically great as 5000 meters"?
"The concentration of N2 in the atmosphere is high . . ."
Does this mean that N2 concentrations are large, or that N2 is concentrated high in the atmosphere?
"The range of the tide is high at this location . . ."
Does this mean that the range is large, or that high tide seems to come far up the shoreline?
"Rainfall is higher in the Biddly Mountains than in the Biggly Mountains, which means that . . .."
Does this mean that the amount of rainfall is greater in the Biddly Mountains than in the Biggly Mountains, or that the elevation of the rainfall is higher, with some resultant meteorological effect?
The same applies to words for changing magnitude and changing elevation. Would "rising methane levels" refer to an increase the concentration of methane in one reservoir or an upward flux of methane? For a non-geoscience example, consider USA Today's report of May 8, 2009, that had the headline "Air traffic falling more slowly" and that distressingly began "Passenger air traffic is still falling . . .".
There is also a more general page on writing scientific papers, a page on scientific papers for Railsback's (and probably others') classes, a page on writing reviews of manuscripts at the request of editors of journals, and a page on writing scientific grant proposals .
Some other links on scientific writing:
"The Science of Scientific Writing" (George D. Gopen and Judith A. Swan, American Scientist, Volume 78)
"How to write a paper in scientific style and journal format"
"Tips for Scientific Writing" from NOAA
A page on "Correct SI-metric usage"
Email to Railsback (firstname.lastname@example.org)
Railsback's main web page
UGA Geology Department web page