The International Journal for the Rapid Publication of Current Research in Organic Geochemistry and Biogeochemistry
The Official Journal of the European Association of Organic Geochemists

Submission checklist
It is hoped that this list will be useful during the final checking of an article prior to sending it to an Editor for review. Please consult the Guide for Authors for further details of any item.

Ensure that the following items are present:

• One Author designated as corresponding Author:• E-mail address • Full postal address• Telephone and fax numbers• All necessary files have been uploaded• Keywords• All figure captions• All tables (including title, description, footnotes)

Further considerations

• Manuscript should have been "spellchecked"• References must be in the correct format for Organic Geochemistry• All references mentioned in the Reference list must be cited in the text and vice versa• Permission should have been obtained for use of copyrighted material from other sources (including the Web)• Colour figures are clearly marked as being intended for colour reproduction on the Web (free of charge) and in print, or to be reproduced in colour on the Web (free of charge) and in black-and-white in print• If colour only on the Web is required, black and white versions of the figures should also supplied for printing purposes

For any further information please contact the Author Support Department at authorsupport@elsevier.com.

General

Submission of papers: Authors are requested to submit their original manuscript and figures via the Elsevier Electronic Submission system ( http://ees.elsevier.com/OG) to either Dr. Lloyd R. Snowdon or Professor J.R. Maxwell FRS, Co-Chief Editors (see detailed instructions below). It is essential to give a fax number and e-mail address when submitting a manuscript. Articles must be written in good English. Submission of an article implies that the work described has not been published previously (except in the form of an abstract or as part of a published lecture or academic thesis), that it is not under consideration for publication elsewhere, that its publication is approved by all Authors and tacitly or explicitly by the responsible authorities where the work was carried out, and that, if accepted, it will not be published elsewhere in the same form, in English or in any other language, without the written consent of the Publisher. A statement to this effect should be included in a cover letter accompanying the manuscript and over the signature of the corresponding author.

Types of Contributions: Papers may be published as a Full Paper, a Note or a Discussion/Reply. A full paper should describe original research in the general area of Organic Geochemistry (see Aims and Scopes). A note is a short (see strict length limits below) original contribution, which can be used to inform readers of preliminary or limited results of research. Papers in the form of a Discussion/Reply will be published when a reader wishes to comment on a paper published previously. This format will be of two back-to-back short communications, one from the communicator and one from the original author(s).

Paper Length: Papers generally average 10-15 printed pages, including tables, figures and references. A full page of text in Organic Geochemistry contains about 850 words. For Notes, the manuscript MUST NOT EXCEED 10 PAGES OF A4 SIZE, including text, references and all tables, figures, appendices, legends, etc. A 3 cm border must be left all round each page: the preferred type is Century Schoolbook (12 pt). The type MUST be double spaced (i.e. about 10 mm between the centre of lines). Papers of more than 10 pages that are submitted as NOTES will automatically be treated as normal submissions and will not be fast tracked.

Scientific review: Manuscripts will be reviewed by a minimum of two referees and will be considered for publication on the basis of originality of the contribution and the recommendations of referees and editors. Authors are requested to provide a list of several possible referees with appropriate mail and e-mail addresses. You may also mention persons whom you would prefer not to review your paper.

Copyright: Upon acceptance of an article, Authors will be asked to transfer copyright (for more information on copyright see http://www.elsevier.com/copyright). This transfer will ensure the widest possible dissemination of information. A letter will be sent to the corresponding Author confirming receipt of the manuscript. A form facilitating transfer of copyright will be provided. If excerpts from other copyrighted works are included, the Author(s) must obtain written permission from the copyright owners and credit the source(s) in their article. Elsevier has preprinted forms for use by Authors in these cases: contact Elsevier's Rights Department, Oxford, UK: phone (+44) 1865 843830, fax (+44) 1865 853333, e-mail permissions@elsevier.com. Requests may also be completed online via the Elsevier homepage ( http://www.elsevier.com/locate/permissions).

Authors' rights
As an author you (or your employer or institution) may do the following:
- make copies (print or electronic) of the article for your own personal use, including for your own classroom teaching use
- make copies and distribute such copies (including through e-mail) of the article to research colleagues, for the personal use by such colleagues (but not commercially or systematically, e.g., via an e-mail list or list server)
- post a pre-print version of the article on Internet websites including electronic pre-print servers, and to retain indefinitely such version on such servers or sites
- post a revised personal version of the final text of the article (to reflect changes made in the peer review and editing process) on your personal or institutional website or server, with a link to the journal homepage (on elsevier.com)
- present the article at a meeting or conference and to distribute copies of the article to the delegates attending such a meeting
- for your employer, if the article is a 'work for hire', made within the scope of your employment, your employer may use all or part of the information in the article for other intra-company use (e.g., training)
- retain patent and trademark rights and rights to any processes or procedure described in the article - include the article in full or in part in a thesis or dissertation (provided that this is not to be published commercially)
- use the article or any part thereof in a printed compilation of your works, such as collected writings or lecture notes (subsequent to publication of your article in the journal)
- prepare other derivative works, to extend the article into book-length form, or to otherwise re-use portions or excerpts in other works, with full acknowledgement of its original publication in the journal

Online submission to the journal prior to acceptance

Submission to this journal proceeds totally online. Use the following guidelines to prepare your article. Via http://ees.elsevier.com/OG you will be guided stepwise through the creation and uploading of the various files. The system automatically converts source files to a single Adobe Acrobat PDF version of the article, which is used in the peer review process. Please note that even though manuscript source files are converted to PDF at submission for the review process, these source files are needed for further processing after acceptance. All correspondence, including notification of the Editor's decision and requests for revision, takes place by e-mail and via the Author's homepage, removing the need for a hard copy paper trail.

The above represents a very brief outline of this form of submission. It can be advantageous to print this "Guide for Authors" section from the site for reference in the subsequent stages of article preparation.

Electronic format requirements for accepted articles

General points
We accept most word processing formats, but Word or WordPerfect is preferred. Always keep a backup copy of the electronic file for reference and safety. Save your files using the default extension of the program used.

Word processor documents
It is important that the file be saved and uploaded in the native format of the word processor used. The text should be in single column format. Keep the layout of the text as simple as possible. Most formatting codes will be removed and replaced on processing the article. In particular, do not use the word processor's options to justify text or to hyphenate words. However, do use bold face, italics, subscripts, superscripts etc. Do not embed "graphically designed" equations or tables, but prepare these using the word processor's facility. When preparing tables, if you are using a table grid, use only one grid for each individual table and not a grid for each row. If no grid is used, use tabs, not spaces, to align columns. The electronic text should be prepared in a way very similar to that of conventional manuscripts (see also the Guide to Publishing with Elsevier: http://www.elsevier.com/locate/guidepublication). Do not import the figures into the text file but, instead, indicate their approximate locations directly in the electronic text and on the manuscript. See also the section on Preparation of electronic illustrations.
To avoid unnecessary errors you are strongly advised to use the "spellchecker" function of your word processor.

Preparation of text

Presentation of manuscript

General
Please write your text in good English (American or British usage is accepted, but not a mixture of these). Italics are not to be used for expressions of Latin origin, for example, in vivo, et al., per se. Use decimal points (not commas); use a comma for thousands (10,000 and above). Language Polishing. Authors who require information about language editing and copyediting services pre- and post-submission please visit http://www.elsevier.com/locate/languagepolishing or contact authorsupport@elsevier.com for more information. Please note Elsevier neither endorses nor takes responsibility for any products, goods or services offered by outside vendors through our services or in any advertising. For more information please refer to our Terms & Conditions. http://www.elsevier.com/termsandconditions

Provide the following data on the title page (in the order given).

Title. Concise and informative. Titles are often used in information-retrieval systems. Avoid abbreviations and formulae where possible. Lower case should be used, except for the first letter of the first word or of names.
Author names and affiliations. Where the family name may be ambiguous (e.g., a double name), please indicate this clearly. Present the Authors' affiliation addresses (where the actual work was done) below the names. Indicate all affiliations with a lower-case superscript letter immediately after the Author's name and in front of the appropriate address. Provide the full postal address of each affiliation in italics, including the country name, and, if available, the e-mail address of each Author.
Corresponding Author. Clearly indicate who is willing to handle correspondence at all stages of refereeing and publication, also post-publication. Ensure that telephone and fax numbers (with country and area code) are provided in addition to the e-mail address and the complete postal address.
Present/permanent address. If an Author has moved since the work described in the article was done, or was visiting at the time, a "Present address" (or "Permanent address") may be indicated as a footnote to that Author's name. The address at which the Author actually did the work must be retained as the main, affiliation address. Superscript Arabic numerals are used for such footnotes.
Abstract. A concise and factual abstract is required (maximum length 250 words). The abstract should state briefly the purpose of the research, the principal results and major conclusions. A structured abstract is required. For this, a recent copy of the journal should be consulted. An abstract is often presented separate from the article, so it must be able to stand alone. References should therefore be avoided, but if essential, they must be cited in full, without reference to the reference list.
Non-standard or uncommon abbreviations should be avoided, but if essential they must be defined at their first mention in the abstract itself.
Keywords. Immediately after the abstract, provide a maximum of 10 keywords, avoiding general and plural terms and multiple concepts (avoid, for example, "and", "of"). Be sparing with abbreviations: only abbreviations firmly established in the field may be eligible. These keywords will be used for indexing purposes.
Abbreviations. Define abbreviations that are not standard in this field at their first occurrence in the article: in the abstract but also in the main text after it. Ensure consistency of abbreviations throughout the article.
N.B. Acknowledgements. Collate acknowledgements, including information on grants received, in a separate section at the end of the article and do not, therefore, include them on the title page, as a footnote to the title or otherwise. Authors are also strongly encouraged to acknowledge the referees.

Arrangement of the article

Subdivision of the article. Divide your article into clearly defined and numbered sections. Subsections should be numbered 1.1 (then 1.1.1, 1.1.2, ?), 1.2, etc. (the abstract is not included in section numbering). Use this numbering also for internal cross-referencing: do not just refer to "the text." Any subsection may be given a brief heading. Each heading should appear on its own separate line.
References. See separate section, below.
Figure captions, tables, figures, schemes. Present these, in this order, at the end of the article. They are described in more detail below. Further, high-resolution graphics files must be provided separately (see Preparation of illustrations).
Text graphics. Present incidental graphics not suitable for mention as figures, plates or schemes at the end of the article and number them "Graphic 1", etc. Their precise position in the text can then be indicated. See further under the section, Preparation of illustrations. If you are working with LaTeX and have such features embedded in the text, these can be left, but such embedding should not be done specifically for publishing purposes. Furthermore, high-resolution graphics files must be provided separately (see Preparation of illustrations).

Specific remarks

Mathematical formulae. Present simple formulae in the line of normal text where possible. In principle, variables are to be presented in italics. Use the solidus (/) instead of a horizontal line, e.g., X/Y rather than
X
Y
Powers of e are often more conveniently denoted by exp.
Number consecutively any equations that have to be displayed separate from the text (if referred to explicitly in the text).

Footnotes. Footnotes should be used sparingly. Number them consecutively throughout the article, using superscript Arabic numbers. Many word processors build footnotes into the text, and this feature may be used. Should this not be the case, indicate the position of footnotes in the text and present the footnotes themselves on a separate sheet at the end of the article. Do not include footnotes in the Reference list.
Table footnotes. Indicate each footnote in a table with a superscript lowercase letter.

Tables. Number tables consecutively in accordance with their appearance in the text. Place footnotes to tables below the table body and indicate them with superscript lowercase letters. Avoid vertical rules. Be sparing in the use of tables and ensure that the data presented in tables do not duplicate results described elsewhere in the article. Tables must be submitted as word processor tables or in spreadsheets rather than bitmap or image files to facilitate editing and typesetting.

Nomenclature and units. Follow internationally accepted rules and conventions: use the international system of units (SI). If other quantities are mentioned, give their equivalent in SI. Include a space between the number and the following units or abbreviation except for %, the symbol for per mil and °, ' and " when used in latitude and longitude. In Windows use alt[0186] for °, alt[241] for ± and alt[0137] for the symbol for per mil.

DNA and amino acid sequences. Any nucleotide sequence data reported or referred to in a submitted manuscript must be deposited in one of the three major collaborative databases-DDBJ/EMBL/GenBank-which exchange data on a daily basis. The suggested wording for referring to accession number information is: These sequence data have been submitted to the DDBJ/EMBL/GenBank databases under accession number U12345. Addresses are as follows: DDBJ email: ddbjsub@ddbj.nig.ac.jp (for data submissions), URL: http://www.ddbj.nig.ac.jp/; EMBL email: datasubs@ebi.ac.uk, URL: http://www.ebi.ac.uk/; GenBank email: gb-sub@ncbi.nlm.nih.gov, URL: http://www.ncbi.nlm.nih.gov/.

Preparation of supplementary data. Elsevier accepts supplementary material to support and enhance your scientific research. Supplementary files offer the Author additional possibilities to publish supporting applications, movies, animation sequences, high-resolution images, background datasets, sound clips and more. Supplementary files supplied will be published online alongside the electronic version of your article in Elsevier Web products, including ScienceDirect: http://www.sciencedirect.com. In order to ensure that your submitted material is directly usable, please ensure that data is provided in one of our recommended file formats. Authors should submit the material in electronic format together with the article and supply a concise and descriptive caption for each file. For more detailed instructions please visit our artwork instruction pages at the Author Gateway at http://www.elsevier.com/artworkinstructions.

References

Responsibility for the accuracy of bibliographic citations lies entirely with the Authors.

All publications cited in the text should be presented in a list of references following the text of the manuscript. Reference to manuscripts "in preparation" or "submitted" are not allowed. In the text refer to the author's name (without initials) and year of publication (e.g. "Since Peterson (1993) has shown that?" or "This is in agreement with results obtained later (Kramer, 1994)". For three or more authors use the first author followed by "et al.", in the text. The citations should be chronological, oldest first, whereas the list of references should be arranged alphabetically by authors' names. References by the same author(s) should be arranged chronologically. The manuscript should be carefully checked to ensure that the spelling of authors' names and publication dates are exactly the same in the text as in the reference list.

References must be given in the following form with particular attention to the punctuation and the fully written out journal names:

Reference: Lee, G.S.H., Wilson, M.A., Young, B.R., 1998. The application of the "watergate" suppression technique for analysing humic substances by nuclear magnetic resonance. Organic Geochemistry 28, 549-559.

Chapter in a book: Baker, E.W., Louda, J.W., 1986. Porphyrins in the geological record. In: Johns, R.B. (Ed.), Biological Markers in the Sedimentary Record. Elsevier, Oxford, pp. 121-225.

Book: Hunt, J.M., 1996. Petroleum Geochemistry and Geology, 2nd Edition. Freeman, New York.

Report: Zhang, E., Tang, Y., Hill, R., Liu, J., Foss, D.C., Chung, E.Y., 1997. Kinetic and basin modeling of gas generation from the Cameo Coal, Piceance Basin, northwest Colorado. Chevron internal report.

Meeting Abstract: Comer, J.B., Payne, D.F., Sibo, W., 1997. Modeling burial and thermal history of the Mesaverde Group, Piceance Basin, Colorado - Implications for gas generation from coals. Abstract. American Association of Petroleum Geologists Annual Meeting, Dallas, p. A22.

Conference Proceedings: Li, M., Osadetz, K.G., Fowler, M.G., Snowdon, L.R., Stasiuk, L.D., Yao, H., Hwang, R.J., Jenden, P., Grant, B., Idiz, E., 1998. Case studies on secondary oil migration in the Williston Basin Symposium. Saskatchewan Geological Survey Special Publication 13, pp. 247-253.

Preparation of illustrations

Preparation of electronic illustrations

General points

• Make sure you use uniform lettering and sizing of your original artwork.
• Save text in illustrations as "graphics" or enclose the font.
• Only use the following fonts in your illustrations: Arial, Courier, Helvetica, Times, Symbol.
• Number the illustrations according to their sequence in the text.
• Use a logical naming convention for your artwork files.
• Provide all illustrations as separate files.
• Provide captions to illustrations separately.
• Produce images near to the desired size of the printed version.

A detailed guide on electronic artwork is available on our website: http://www.elsevier.com/artworkinstructions You are urged to visit this site; some excerpts from the detailed information are given here.

Formats
Regardless of the application used, when your electronic artwork is finalised, please "save as" or convert the images to one of the following formats (Note the resolution requirements for line drawings, halftones, and line/halftone combinations given below.):

EPS: Vector drawings. Embed the font or save the text as "graphics".
TIFF: Colour or greyscale photographs (halftones): always use a minimum of 300 dpi.
TIFF: Bitmapped line drawings: use a minimum of 1000 dpi.
TIFF: Combinations bitmapped line/half-tone (colour or greyscale): a minimum of 500 dpi is required.
DOC, XLS or PPT: If your electronic artwork is created in any of these Microsoft Office applications please supply "as is".

Please do not:
• Supply embedded graphics in your word processor (spreadsheet, presentation) document;
• Supply files that are optimised for screen use (like GIF, BMP, PICT, WPG); the resolution is too low;
• Supply files that are too low in resolution;
• Submit graphics that are disproportionately large for the content.

Captions
Ensure that each illustration has a caption. Supply captions separately, not attached to the figure. A caption should comprise a brief title (not on the figure itself) and a description of the illustration. Keep text in the illustrations themselves to a minimum but explain all symbols and abbreviations used.

Line drawings
The lettering and symbols, as well as other details, should have proportionate dimensions, so as not to become illegible or unclear after possible reduction; in general, the figures should be designed for a reduction factor of two to three. The degree of reduction will be determined by the Publisher. Illustrations will not be enlarged. Consider the page format of the journal when designing the illustrations.
Do not use any type of shading on computer-generated illustrations.

Photographs (halftones)
Remove non-essential areas of a photograph. Where necessary, insert a scale bar in the illustration (not below it), as opposed to giving a magnification factor in the caption.

Colour illustrations
Please make sure that artwork files are in an acceptable format (TIFF, EPS or MS Office files) and with the correct resolution. If, together with your accepted article, you submit usable colour figures then Elsevier will ensure, at no additional charge, that these figures will appear in colour on the Web (e.g., ScienceDirect and other sites) regardless of whether or not these illustrations are reproduced in colour in the printed version. For colour reproduction in print, you will receive information regarding the costs from Elsevier after receipt of your accepted article. Please indicate your preference for colour in print or on the Web only. For further information on the preparation of electronic artwork, please see http://www.elsevier.com/artworkinstructions.

Please note: Because of technical complications which can arise by converting colour figures to "grey scale" (for the printed version should you not opt for colour in print) please submit in addition usable black and white versions of all the colour illustrations.

Proofs

One set of page proofs in PDF format will be sent by e-mail to the corresponding Author (if we do not have an e-mail address then paper proofs will be sent by post). Elsevier now sends PDF proofs which can be annotated; for this you will need to download Adobe Reader version 7 available free from http://www.adobe.com/products/acrobat/readstep2.html. Instructions on how to annotate PDF files will accompany the proofs.
If you do not wish to use the PDF annotations function, you may list the corrections (including replies to the Query Form) and return to Elsevier in an e-mail. Please list your corrections quoting line number. If, for any reason, this is not possible, then mark the corrections and any other comments (including replies to the Query Form) on a printout of your proof and return by fax, or scan the pages and e-mail, or by post.
Please use this proof only for checking the typesetting, editing, completeness and correctness of the text, tables and figures. Significant changes to the article as accepted for publication will only be considered at this stage with permission from the Editor. We will do everything possible to get your article published quickly and accurately. Therefore, it is important to ensure that all of your corrections are sent back to us in one communication: please check carefully before replying, as inclusion of any subsequent corrections cannot be guaranteed. Proofreading is solely your responsibility. Note that Elsevier may proceed with the publication of your article if no response is received.

Electronic offprints (e-offprints)

The corresponding author, at no cost, will be provided with a PDF file of the article via e-mail or, alternatively, 25 free paper offprints. The PDF file is a watermarked version of the published article and includes a cover sheet with the journal cover image and a disclaimer outlining the terms and conditions of use.