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US Geological Survey Open-File Report 03-471: Digital Mapping

US Geological Survey Open-File Report 03-471: Digital Mapping

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CHRONOS—Integrated Stratigraphic Databases, the Development of an International Standard Time Scale and the Interoperability with Time Scales of U.S. State Surveys By Bruce R. Wardlaw

U.S. Geological Survey 926A National Center Reston, VA 20192 Telephone: 703-648-5288 Email: [email protected]

INTRODUCTION The implementation of CHRONOS will involve the following tasks: Modern Earth system history research increasingly depends upon the analysis of voluminous multidisci- • Progressively establish and interlink critical plinary, time-calibrated data. The process of determining thematic database networks for life through time, the availability or even the existence of Earth history data radiometric age, climate through time, chemical remains a time-consuming and error-prone enterprise and sedimentary cycles through time, core-to-crust because there are no centralized depositories or Web-en- dynamics through time (such as magnetostratig- abled means for locating and retrieving data. The goal of raphy), and other components of Earth system CHRONOS is to unify current and future stratigraphic history; databases into a powerful system for producing a dynamic • Establish central CHRONOS portal to access and global time scale for Earth history and for understand- analyze major component data types for research- ing the complex relationships of past geologic, climatic ers and the general public; and evolutionary trends. Web-services and an extensive • Develop advanced tools and visualization capabili- on-line suite of toolboxes will allow global researchers ties that investigators can apply to uploaded data in and the general public to access, analyze and visualize their on space on a CHRONOS server or download CHRONOS stratigraphic information. Another goal, and to their own system; the centerpiece of the CHRONOS system, is a vastly • Assemble a high-precision ʻStandard Geological improved high-resolution geological time scale. Time Scaleʼ under the aegis of the International A logical of tasks is planned to accomplish Commission on Stratigraphy; these goals, with the ultimate goal being for all geo- • Coordinate an outreach program with educational scientists to be able to apply the CHRONOS system of modules and informative demonstrations of the integrated databases for deciphering the complex interac- CHRONOS system; and tions of the Earth system through all of geologic time. In • Study four critical time-slices of Earth history as addition to its primary goals of enabling networking of ʻtest-bedʼ investigations, using the expanding capa- international databases and facilitating creative research, bilities of the information-technology infrastructure the CHRONOS outreach programs will promote educa- and toolkits of the assembled CHRONOS system. tion of Earthʼs fascinating history. CHRONOS is a system within the larger effort of The four time-slice studies address longstanding the National Science Foundation for cyberinfrastructure scientifi c questions of societal relevance and interest in the earth sciences (called Geoinformatics). It will be a ( life explosion, - catastrophic distributed system with a single portal at a central hub that extinctions, middle super-greenhouse world, will provide information technology expertise and tools and middle climate transitions; see fi g. 2). Each and link the various thematic nodes or networks, projects, involves different types and qualities of data and will and databases constituting CHRONOS (fi g. 1). improve and refi ne marine and continental data cor-

79 80 DIGITAL MAPPING TECHNIQUES ʻ03

Figure 1. Schematic of the distributed CHRONOS system.

Figure 2. Time Slice Projects of CHRONOS. CHRONOS—INTEGRATED STRATIGRAPHIC DATABASES 81 relations at the global scale. The ultimate goal is for all The fi rst box leads to:http://www.micropress.org/ geoscientists to be able to apply the CHRONOS system of stratigraphy/carper.htm where we fi nd full references and integrated databases for deciphering the complex interac- section and map; the Episodes article also is available tions of the Earth system through all of geologic time. digitally. From a completely different source identifi ed HOW THE CHRONOS INTERACTIVE by CHRONOS, we would get a current reinterpreta- tion of the lineages from the GSSP (http: NETWORK WILL WORK WITH DMT //www.kgs.ukans.edu/, fi g. 4), as found in Wardlaw and AND THE U.S STATE SURVEYS others (2003). From the same publication, the conodont ranges from Kansas are shown (fi g. 5). A brief history of An example of how CHRONOS will support the the placement of the Permian boundary in Kansas would goals of the Digital Mapping Techniques workshops be available from Paleodata (the National Geologic Map is the seamless way it will relate local state geologi- Databaseʼs National Paleontologic Database, fi g. 6) cal survey time scales to the International Time Scale. which will show where R. C. Moore placed the boundary Initial information and links for both local and inter- at the top of the Brownville Limestone, which became national scales will be available from the National the “traditional” boundary; and where the boundary was Geologic Map Databaseʼs Geological Names Lexicon modifi ed using the fi rst occurrence of theStreptognatho- (“GEOLEX”, http://ngmsvr.wr.usgs.gov/Geolex/). dus constrictus conodont zone (an early contender for the The current international scale is available from the boundary defi nition) placed by Baars and others (1994) International Commission on Stratigraphy (ICS, http: at the base of the Neva Limestone. However, Boardman //www.micropress.org/stratigraphy/index.htm) or a and others (1998) clearly show the fi rst occurrence ofS. slightly modifi ed version (retaining the Tertiary) from constrictus and other species that make up the zone in the U. S. Geological Survey (USGS), soon to be avail- the underlying Burr Limestone. The fi rst occurrence of able on GEOLEX (fi g. 3). S. isolatus (the international boundary indicator) is in the As an example of how CHRONOS will function, Bennett Shale of the Red Eagle Limestone. let us imagine that we want to know where the currently Further, in the reference section for the Carbonifer- internationally-defi ned -Permian boundary ous-Permian boundary at Usolka in the Urals, Russia, falls in the sections in Kansas and West Texas and how it there are found volcanic tuffs centimeters below and relates to the boundary recognized by those states. From above the fi rst occurrence ofStreptognathodus isolatus the CHRONOS portal, you would be linked to the ICS that yield abundant zircons (Permophiles no. 39, http: site containing the Global Stratotype Section and Points //pri.boisestate.edu/permophiles/issue39.pdf). Both hori- (GSSPʼs) for all formally accepted boundaries of the ICS zons indicate virtually the same date, and though prelimi- (currently, go to http://www.micropress.org/stratigraphy/ nary, are dated at 299 million before present(Ma). index.htm, and select “GSSPʼs”). The Carboniferous- This provides a solid age that can be applied to both Permian boundary information displayed is as follows: Kansas and West Texas sections. Again, from the ICS base Conodont, lowest occurrence of 27 m above base , base Ci- isolatus within the of Bed 19, Aidaral- Episodes 21 suralian Series, S. “wabaunsensis” conodont chrono- ash Creek, Ak- Ratifi ed, 1996 (1), p.11 base Permian cline. 6 m higher is lowest fusilinid töbe, southern Ural System foraminifer Sphaeroschwagerina Mountains, north- ern Kazakhstan 82 DIGITAL MAPPING TECHNIQUES ʻ03

Figure 3. International Stratigraphic Chart as modifi ed by USGS. CHRONOS—INTEGRATED STRATIGRAPHIC DATABASES 83

2000, http://pri.boisestate.edu/permophiles/issue36.pdf) which follows:

“Preliminary Placement of the International Permian Working Standard to the Glass Moun- tains, Texas”

Bruce R. Wardlaw, U.S. Geological Survey, Res- ton, VA Vladimir I. Davydov, Permian Research Institute, Boise State Univ., Boise, ID

The International Lower Permian Working Standard is based on the conodont distributions in the southern Urals, Kansas, and West Texas. Asselian is defi ned on the fi rst appearance of Streptognathodus isolatus. This occurs at the base of the Bennett Shale of the Red Eagle Limestone in Kansas. The current working defi nition for the base of the is the First Appear- ance (FA) of Streptognathodus barskovi (sensu strictu). This occurs in the Eiss Limestone of the Bader Limestone in Kansas and is very close to the FA of merrilli in the upper part of the Eiss. The working defi nition of the base of the is the FA of S. fl orensis or Swee- tognthus whitei, which both fi rst appear in the base of the Florence Limestone of the Barnston Formation in Kansas. After Barneston deposition the Kansas section remains very shallow during marine incursions and only sparse to common Sweetognathus or Rabegnathus faunas are re- covered. The working standard for conodont zonation is based on the distribution of from the Glass Mountains, Texas. The working defi nition of the base of the Kungurian is the FA of Neostreptognathodus “exsculptus”. Figure 4. Interpretation of Streptognathodus conodont The Grey Limestone Member of the Gap- lineages from the GSSP of the Permian at Aidaralash tank Formation is a shallow-water carbonate that Creek, Kazakhstan; section shown as numbered beds forms the top of the formation. Conodont faunas (from Wardlaw and others, 2003). are sparse, but the base of the Grey Limestone Member contains a conodont fauna that correlates to the Foraker Limestone with the overlap of the ending range of Streptognathodus brownvillensis website, information on relevant radiometric dates utilized and S. elongatus. The top of the Grey Limestone in constructing the Phanerozoic time scale is available contains a conodont fauna that correlates to the (fi g. 7, from Gradstein and Ogg, 2004, to be made avail- Grenola Limestone with Streptognathodus ne- able through ICS). vaensis and S. elongatus. Therefore, the Carbon- For the necessary stratigraphic information for iferous-Permian boundary is located within the West Texas, we would be linked to a digital copy of Grey Limestone. an article from Permophiles issue number 36 (June, 84 DIGITAL MAPPING TECHNIQUES ʻ03

We want more substantial information, so CHRO- NOS would conduct an author search for Wardlaw and First Stratigraphic for Davydov, and fi nd that there is no further informa- Appearance of Position tion published by these authors on the placement of conodonts in the lower part of the West Texas regional N. “exsculptus” 17 m above base, stratotype. However, in our author search, we fi nd all Skinner Ranch Formation of Wardlawʼs fi eld information is available via Paleo- S. barskovi 52 m above base, Strat (https://www.paleostrat.com), a paleontologic and Neal Ranch Formation stratigraphic information system that allows us to see the S. nevaensis Top of Grey measured section (fi g. 8), information on each sample, Limestone Member and the conodont faunas recovered and digital images of S. elongatus Base of Grey the representative specimens. Thus, we are assured of the Limestone Member placement of the Carboniferous-Permian boundary in the Wolfcamp Hills/Geologist Canyon section, the regional The Neal Ranch Formation is dominated by stratotype of the Wolfcampian. prodelta siltstones with common plant debris and CHRONOS will bring all this disparate information limestone and limestone conglomerate interbeds. together for the user. The sources of information also will The limestones yield a fair conodont fauna. At be accessible, so that additional ideas and questions can 52 m above the base Streptognathodus barskovi, be posed by the user. S. isolatus and Sweetongnathus merrilli occur (equivalent to bed 12 of Ross, 1963). The over- ACKNOWLEDGMENTS lap of barskovi and isolatus indicates the base of the S. barskovi zone. Streptognathodus barskovi Much of the description of CHRONOS comes occurs higher at 71 m where it occurs with S. from the interaction of the Steering Committee and postconstrictus which indicates the upper part of their work on writing the NSF proposal (see http:// its zone. www.CHRONOS.org). The author was only one of many The Lenox Hills Formation is largely delta participants and is indebted to all of CHRONOSʼ cre- conglomerates and does not yield conodonts. ators. The author is solely responsible for the time scale However, in the Dugout Mountain area, it con- interpretations. I thank David Soller for a rigorous review tains common limestone which yields a sparse of the article. fauna of Sweetognathus whitei and Neostrepto- transitus. This fauna indicates the up- REFERENCES per Artinskian. Conodonts do not well constrain Baars, D. L., Ross, C. A, Ritter, S. M., and Maples, C. G., 1994, the Sakmarian-Artinskian boundary. Proposed repositioning of the -Permian The Skinner Ranch formation is largely lime- boundary in Kansas, in Baars, D. L., compiler, Revision of stone and limestone conglomerate with abundant stratigraphic nomenclature in Kansas: Kansas Geological conodont fuanas. In its type section it contains Survey Bulletin 230, p. 5-10. Neostreptognathodus pequopensis at its base. At Boardman, D. R., II, Nestell, M. K., and Wardlaw, B. R., 1998, 17 m, a plethora of species of Uppermost Carboniferous and lowermost Permian deposi- and Streptognathodus occur, including Neostrep- tion and of Kansas, USA, in Jin, tognathodus “exsculptus” which marks the base Y. G., Wardlaw, B. R., and Wang, Yue, eds., Permian stra- of the Kungurian.” tigraphy, environments and resources, vol. 2, Stratigraphy and environments: Palaeoworld, no. 9, p. 19-32. Gradstein, F. M., and Ogg, J. G., editors, 2004, A 2004: Cambridge University Press (in press). . Since publication of that article, the working defi ni- Ross, C.A., 1963, Standard Wolfcampian Series (Permian), Glass Mountains, Texas: Geological Society of America tions have been refi ned and changed to formal proposals, Memoir 88, 205p. and the defi nition of the Sakmarian has changed from the Wardlaw, B. R., Boardman, D. R., II, and Nestell, M. K., 2003, First Appearance Datum (FAD) of Streptognathodus bar- Conodont biostratigraphy of the uppermost Carboniferous skovi to the FAD of Sweetognathus merrilli (Permophiles and Lower Permian of Kansas: Kansas Geological Survey no. 41, http://pri.boisestate.edu/permophiles/issue41.pdf) Bulletin (in press). CHRONOS—INTEGRATED STRATIGRAPHIC DATABASES 85

Figure 5. Ranges of conodont species in the Kansas section; darker intervals refl ect largely marine deposition, lighter intervals refl ect largely non- or marginal marine deposition (from Wardlaw and others, 2003). 86 DIGITAL MAPPING TECHNIQUES ʻ03

Figure 6. Historical Perm- ian boundary placement in the Kansas section.

Figure 7. Graphi- cal correlation of radiometric ages and stage boundaries of the Permian. CHRONOS—INTEGRATED STRATIGRAPHIC DATABASES 87

Figure 8. Columnar section of Wolfcamp Hills/Geologist Canyon section of Wardlaw and others (2003), and posi- tion of signifi cant conodont samples. Measured in 1983 and recollected in 1984 (from PaleoStrat, defi nition of horizontal scale based on grain size also in PaleoStrat).