ASTM_D_7708_-_14.pdf

Designation:D770814Standard Test Method forMicroscopical Determination of the Reflectance of VitriniteDispersed in Sedimentary Rocks1This standard is issued under the fixed designation D7708;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method covers the microscopical determinationof the reflectance measured in oil of polished surfaces ofvitrinite dispersed in sedimentary rocks.This test method canalso be used to determine the reflectance of macerals other thanvitrinite dispersed in sedimentary rocks.1.2 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.3 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D121 Terminology of Coal and CokeD388 Classification of Coals by RankD2797 Practice for Preparing Coal Samples for Microscopi-cal Analysis by Reflected LightD2798 Test Method for Microscopical Determination of theVitrinite Reflectance of CoalE177 Practice for Use of the Terms Precision and Bias inASTM Test MethodsE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method3.Terminology3.1 DefinitionsFor definitions of terms,refer to Terminol-ogy D121.3.2 Abbreviations:3.2.1 Roranmean random reflectance measured in oil.Other organizations may use other abbreviations for meanrandom reflectance.3.3 Definitions of Terms Specific to This Standard:3.3.1 alginite,na liptinite maceral occurring in structuredmorphologies,telalginite,and unstructured morphologies,la-malginite.3.3.2 bituminite,nan amorphous primary liptinite maceralwith low reflectance,occasionally characterized by coloredinternal reflections and weak orange-brown fluorescence,de-rived from bacterial biomass and the bacterial decompositionof algal material and faunal plankton.Bituminite is equivalentto the amorphous organic matter recognized in strew slides ofconcentrated kerogen(1).33.3.2.1 DiscussionBituminite may be distinguished fromvitrinite by lower reflectance,as well as higher fluorescenceintensity if fluorescence is present in vitrinite.Bituminite haspoorly-defined wispy boundaries and may be speckled orunevenly colored whereas vitrinite has distinct boundaries andis blockier and evenly colored.The occurrence of bituminite inassociation with lamalginite and micrinite is common.Rocktype,thermal maturity,and geologic occurrence can be used tointerpret the potential presence of bituminite;for example,bituminite may be expected to occur in lacustrine or marinesettings.It is less commonly present in fluvial or similarproximal depositional environments,where vitrinite may beexpected to occur in greater abundance.3.3.3 chitinozoan,na group of flask-shaped,sometimesornamented marine microfossils of presumed metazoan originwhich are composed of pseudochitin proteinic material andwhich occur individually or in chains.Chitinozoan cell wallsare thin,opaque to translucent,and range from dark gray towhite in reflected white light similar to vitrinite.Chitinozoansare common in Ordovician to Devonian marine shales.3.3.4 conodont,nthe phosphatic,tooth-like remains ofmarine vertebrate worm-like animals present from the Cam-brian through Triassic,composed predominantly of apatitewith subordinate amounts of organic matter.Conodont mor-phology is variable,but often well-defined denticles and blades1This test method is under the jurisdiction of ASTM Committee D05 on Coaland Coke and is the direct responsibility of Subcommittee D05.28 on PetrographicAnalysis of Coal and Coke.Current edition approved May 1,2014.Published May 2014.Originally appearedin 2011 as D7708-11.DOI:10.1520/D770814.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.3The boldface numbers in parentheses refer to a list of references at the end ofthis standard.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 are preserved.In reflected white light examination conodontsrange from pale yellow to light brown to dark brown and toblack.3.3.5 fusinite,nan inertinite maceral distinguished princi-pally by the preservation of some feature(s)of the plant cellwall structure,high relief,and reflectance substantially higherthan first cycle vitrinite in the same sample.When less than50-m in size this maceral is assigned to inertodetrinite.