General

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and tacitly or explicitly by the responsible authorities where the work was carried out, and that, if accepted, it will not be published elsewhere in the same form, in English or in any other language, without the written consent of the Publisher.

Online submission to the journal prior to acceptance

Journal of Petroleum Science and Engineering uses an online, electronic submission system. By accessing the website http://ees.elsevier.com/petrol you will be guided stepwise through the creation and uploading of the various files. When submitting a manuscript to Elsevier Editorial System, authors need to provide an electronic version of their manuscript. 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.
The author should specify a category designation for the manuscript (full length article, review article, short communication, etc.). Once the submission files are uploaded, the system automatically generates an electronic (PDF) manuscript, which is then used for reviewing. 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.

In the case of Special Issues, manuscripts should be submitted to the Guest Editor(s). Authors should ensure that they submit manuscripts and meet any additional requirements in line with deadlines set by the Guest Editor(s) to ensure that the entire Special Issue can be published in a timely fashion.

Note: electronic articles submitted for the review process may need to be edited after acceptance to follow journal standards. For this an "editable" file format is necessary. See the section on "Electronic format requirements for accepted articles" and the further general instructions on how to prepare your article below.

Please submit, with the manuscript, the names and addresses of 9 potential Referees. You may also mention persons who 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 the 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


Electronic format requirements for the articles

General points
We accept most wordprocessing formats, but Word, WordPerfect or LaTeX 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. No changes to the accepted version are permissible without the explicit approval of the Editor

Wordprocessor documents
It is important that the file be saved in the native format of the wordprocessor 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 wordprocessor'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 wordprocessor'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). 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 wordprocessor.

LaTeX documents If the LaTeX file is suitable, proofs will be produced without rekeying the text. The article should preferably be written using Elsevier's document class "elsart", or alternatively the standard document class "article". The Elsevier LaTeX package (including detailed instructions for LaTeX preparation) can be obtained from the Quickguide at the website: http://www.elsevier.com/latex. It consists of the files: elsart.cls, guidelines for users of elsart, a template file for quick start, and the instruction booklet "Preparing articles with LaTeX".

Preparation of text

Presentation of manuscript

•General points 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 space for thousands (10 000 and above).

English language help service: Upon request, Elsevier will direct authors to an agent who can check and improve the English of their paper (before submission). Please contact authorsupport@elsevier.com for further information.

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

1. Title
Concise and informative. Titles are often used in information-retrieval systems. Avoid abbreviations and formulae where possible.

2. 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, including the country name, and, if available, the e-mail address of each author.

3. 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.

4. 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.

5. Abstract
A concise and factual abstract is required. In general, the abstract should state briefly the purpose of the research, the principal methods and data used, the principal results and major conclusions. 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.

6. Keywords
Immediately after the abstract, provide a maximum of 6 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.

• Structure the main part of the article as follows:


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.

1. Introduction
State the objectives of the work and provide an adequate background, avoiding a detailed literature survey or a summary of the results.

2. Regional setting
For papers that focus on an area, provide a brief synopsis of the physical and geological characteristics of the area, sufficient to give the new work context, but again avoid a detailed literature survey.

3. Materials and methods
Provide sufficient detail on methods to allow the work to be reproduced. Methods already published should be indicated by a reference: only relevant modifications should be described. Samples should normally be positioned on a map or in a table. However, lengthy tables of precise positions should be submitted as electronic files for Supplementary Data (see below)

4. Results
This should highlight the key results (and not repeat material already in figures or tables) and summarise the direct implications of these results.

5. Discussion This should explore the inter-relationships of different data sets and the broader significance of the results. It may include limited speculation, that will not appear in the conclusions.

6. Conclusions
The short Conclusions section should summarise the conclusions of the study that have been firmly established. It should not duplicate either the Abstract or the Discussion.

7. Acknowledgements
Place acknowledgements, including information on grants received, before the references, in a separate section

8. Appendices
If there is more than one appendix, they should be identified as A, B, etc. Formulae and equations in appendices should be given separate numbering: (Eq. A.1), (Eq. A.2), etc.; in a subsequent appendix, (Eq. B.1) and so forth.

9. References
See separate section, below.

10. Figure legends, tables, figures, schemes
Present these, in this order, at the end of the article. They are described in more detail below. High-resolution graphics files must always be provided separate from the main text file (see Preparation of illustrations).

• Further information on:

a. 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 defined similarly (both on the manuscript and in the file). See further under the section, Preparation of illustrations.

b. 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).

c. Footnotes
Footnotes should be used sparingly. Number them consecutively throughout the article, using superscript Arabic numbers. Many wordprocessors 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.

d. 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.

e. 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.

f. Preparation of supplementary data
Elsevier now accepts electronic 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 the Author Support website at http://www.elsevier.com/artworkinstructions.

References

1. All references cited in the text are to be listed at the end of the paper. The manuscript should be carefully checked to ensure that the spellings of authors' names and publication years are exactly the same in the text as in the reference list. Do not type author's and editor's names in capitals.

2. In the text refer to the author's name (without initials) and year of publication, followed - if necessary - by a short reference to appropriate pages. Examples: ``Because Peterson (1994) has shown that...''. ``This is in agreement with results obtained later (Kramer, 1995, pp. 12-16)''.

3. If reference is made in the text to publications written by more than two authors the name of the first author should be used, followed by ``et al.''. This indication, however, should never be used in the list of references. In this list names of authors and all co-authors must be given in full.

4. References in the text should be arranged chronologically. The list of references should be arranged alphabetically by authors' names, and chronologically per author. If an author's name in the list is also mentioned with co-authors, the following order should be used: - publications of the single author, arranged according to publication year - - publications of the same author with one co-author, arranged according to publication year -

The following system should be used for arranging references:

a. Journal papers: Names and initials of all authors, year. Title of paper. Journal name (given in full or abbreviated using the International List of Periodical Title Word Abbreviations), volume number (issue number): first and last page numbers of the paper. Example: Elbaz-Poulichet, F., Guan, D.M., Martin, J.M., 1991. Trace metal behaviour in a highly stratified Mediterranean estuary: the Krka (Yugoslavia). Mar. Chem. 32: 211-224.

b. Monographs: Names and initials of all authors, year. Title of the monograph. Publisher, location of publisher, total number of pages. Example: Zhdanov, M.S., Keller, G.V., 1994. The Geoelectrical Methods in Geophysical Exploration. Elsevier, Amsterdam, 346 pp.

c. Edited volume papers: Names and initials of all authors, year. Title of paper. Names and initials of the volume editors, title of the edited volume. Publisher, location of publisher, first and last page numbers of the paper. Example: Thomas, E., 1992. Middle Eocene-late Oligocene bathyal benthic foraminifera (Weddell Sea): faunal changes and implications for ocean circulation. In: D.R. Prothero, W.A. Berggren (Editors), Eocene-Oligocene Climatic and Biotic Evolution. Princeton Univ. Press, Princeton, NJ, pp. 245-271.

d. Conference proceedings papers: Names and initials of all authors, year. Title of paper. Name of the conference. Publisher, location of publisher, first and last page numbers of the paper. Example: Smith, M.W., 1988. The significance of climatic change for the permafrost environment. Final Proc. Int. Conf. Permafrost. Tapir, Trondheim, Norway, pp. 18-23.

e. Unpublished theses, reports, etc.: Names and initials of all authors, year. Title of item. All other relevant information needed to identify the item (e.g., technical report, Ph.D. thesis, institute, etc.). Example: Moustakas, N., 1990. Relationships of morphological and physicochemical properties of Vertisols under Greek climate conditions. Ph.D. Thesis, Agricultural Univ. Athens, Greece.

5. In the case of publications in any language other than English, the original title is to be retained. Titles of publications in non-Latin alphabets should be transliterated, and a note such as `(in Russian)' or `(in Japanese, with English Abstr.)' should be added at the end of the reference.

The following provide examples of appropriate citation formats for non-text and electronic-only information. However, it is requested that a Web site address, or list server message is given as a reference only where the information is unavailable in a more permanent form. If such sources are given, then please give as complete information as possible. Jones, P., 1996. Research activities at Smith Technology Institute. WWW Page, http://www.sti.com/about_us/research.
Smith, F., Peabody, A.N., 1997. Hydrographic data for the Sargasso Sea, July-September 1993, SarSea mission. (Deep-Sea Data Centre, Hull, UK), online, dataset, 740 MB, http://www.dcdc.gov.
Green, A., 1991. Deformations in Acanthaster planci from the Coral Sea, observed during UEA Special Project 7, July 1978. Journal of Pollution Research 14 (7) suppl., CD-ROM, photographic images, 240 MB. James, Z., 1997. Ecological effects of sea wall construction during 1994 at Bridlington, UK. List server Message, Eco-list, 20 October 1995.

Use of the Digital Object Identifier
The digital object identifier (DOI) may be used to cite and link to electronic documents. The DOI consists of a unique alpha-numeric character string which is assigned to a document by the publisher upon the initial electronic publication. The assigned DOI never changes. Therefore, it is an ideal medium for citing a document, particularly Articles in press because they have not yet received their full bibliographic information. The correct format for citing a DOI is shown as follows (example taken from a document in the journal Physics Letters B): doi:10.1016/j.physletb.2003.10.071
When you use the DOI to create URL hyperlinks to documents on the web, they are guaranteed never to change.

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 (and as hardcopy printouts on separate sheets).
- 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://authors.elsevier.com/artwork 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 wordprocessor (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 as a separate section in the manuscript file, 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. Do not mount photographs unless they form part of a composite figure. 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.

Supplementary data
Elsevier now accepts electronic 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 http://www.elsevier.com/artworkinstructions.

Proofs

One set of page proofs in PDF format will be sent by e-mail to the corresponding Author (if no e-mail address is supplied 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. Elsevier 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 Elsevier in one communication: please check carefully before replying, as inclusion of any subsequent corrections cannot be guaranteed. Proofreading is solely your responsibility. Return corrections within 3 days of receipt of the proofs. Should there be no corrections, please confirm this.
The Publisher reserves the right to proceed with publication if corrections are not communicated.

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. Additional reprints can be ordered on a reprint order form which will be sent to the corresponding author of the accepted article by the publisher.

Submission checklist

It is hoped that this list will be useful during the final checking of an article prior to sending it to the journal',s Editor for review. Please consult this 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 uploaded
Keywords
All figure captions
All tables (including title, description, footnotes)

Further considerations

Manuscript has been "spellchecked"
References are in the correct format for this journal
All references mentioned in the Reference list are cited in the text, and vice versa
Permission has 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 only colour on the Web is required, black and white versions of the figures are also supplied for printing purposes

Contact
For queries relating to the general submission of manuscripts (including electronic text and artwork) and the status of accepted manuscripts, please contact Elsevier's Author Support Department, Elsevier B.V., PO Box 2759, 1000 CT Amsterdam, The Netherlands. E-mail: authorsupport@elsevier.nl or visit http://authors.elsevier.com. Fax: +31 (0) 20 485 3752, Tel: +31 (0) 20 485-2535.
Authors can also keep track of the progress of their accepted article, and set up e-mail alerts informing them of changes to their manuscript's status, by accessing the links on http://authors.elsevier.com.