Specific references for data in the papers contained in this volume are given in the documentation files for those data.

Please cite original references when using data

The SEPM volume referenced above presents the results of a coordinated, multidisciplinary study of Cretaceous carbonate and clastic rocks in cores collected along an E-W transect across the old Cretaceous seaway that extended from the Gulf Coast to the Arctic by a team of academic, industry, and U.S. Geological Survey (USGS) scientists. The overall goal of the study was to construct a subsurface transect of mid-Cretaceous strata that were deposited in the U.S. Western Interior Seaway (WIS), ranging from pelagic, organic-carbon rich, marine hydrocarbon source rocks in Kansas and eastern Colorado to nearshore, coal-bearing units in western Colorado and Utah. This transect of cores has provided the basis for paleoenvironmental interpretation of organic-carbon burial in an epicontinental, foreland basin setting. In part, the objectives of our study were motivated by the research emphases outlined by the Cretaceous Rhythms, Events and Resources (CRER) Project of the Global Sedimentary Geology Program.

In particular, the papers in this volume focus on the Graneros Shale, Greenhorn Formation, Carlile Shale, and Niobrara Formation and equivalents in cores from drillholes from western Kansas, eastern Colorado, and eastern Utah. This series of cores provides unweathered samples and continuous, smooth exposures required for geochemical studies, mineralogical investigations, and biostratigraphic studies.

Information for the eastern end of the transect was obtained from a hole that was drilled in 1988 and continuously cored (with better than 90% recovery) by Amoco Production Company in western Kansas (Amoco Rebecca K. Bounds #1, Greeley County, Kansas). A Core from the western end of the transect was obtained in 1991 when the USGS drilled and continuously cored (with better than 98% recovery) a hole in the Kaiparowits Basin near the town of Escalante in south central Utah (USGS Escalante #1) A third hole (USGS Portland #1), was drilled by the USGS and continuously cored (with essentially 100% recovery) in Cretaceous strata in the Cañon City Basin near Florence, Colorado. A fourth hole was originally planned for the San Juan Basin in southwestern Colorado. The need for this hole was eliminated when Mark Leckie and colleagues continuously trenched a section of the Mancos Shale at the northern border of Mesa Verde National Park between Durango and Cortez, Colorado. Other outcrop sections of Mancon Shale and age-equivalent strata also were sampled and studied by Leckie and colleagues, and their results are reported in the SEPM volume. Other pre-existing cores that were used for parts of the study include Plains Resources Schock Errington #1, Sherman County, Kansas; Coquina Oil Corporation Berthoud State #3 and #4, Larimer County, Colorado; and Princeton University PU79 near Pueblo, Colorado. All cores are presently archived in the USGS Core Research Center (USGS-CRC) in Denver.

Amoco Bounds Core

The Amoco Production Company, Rebecca K. Bounds #1 well was drilled in March of 1988 in Section 17, T18S, R42W, Greeley County, Kansas, to a total depth (TD) of 2645 feet (806 meters). Ground level elevation was 3824 feet (1166 meters). The hole was continuously cored from a depth of 522 feet (159 meters) to TD using Amoco's slim-hole high-speed advanced drilling system (SHADS) also known as stratigraphic high-speed advanced drilling system. Coring began in the middle of the Smoky Hill Member (Santonian) of the Niobrara Formation and bottomed in the Mississippian. In January, 1992, the Cretaceous part of the Bounds core (522 -1495 feet; 159-456 meters) was released by Amoco and shipped to the USGS-CRC in Denver. The core was slabbed at the USGS-CRC, and a 2-cm-thick slab of the core is archived there.

USGS Escalante Core

The USGS Escalante #1 well was drilled by the USGS in June of 1991 in Section 36, T35S, R2W, Garfield County, Utah, to a total depth (TD) of 910 feet (277 meters). Ground level elevation was 6000 feet (1829 meters). The hole was continuously cored and logged to TD. Coring recovered all of the Cenomanian/Turonian Tropic Shale, the bottom of the overlying Tibbet Canyon Member of the Straight Cliffs Formation, and the top of the underlying Dakota Group.

USGS Portland Core

The USGS Portland #1 well was drilled by the USGS in June and July of 1992 on the quarry property of Ideal Cement (Holnam Corp.) in Section 2, T19S, R68W, near the town of Florence in Fremont County, Colorado, to a total depth (TD) of 700 feet (213 meters). Ground level elevation was 5200 feet (1585 meters). The hole was continuously cored and logged to TD. Coring began in the middle of the Smoky Hill Member of the Niobrara Formation and bottomed in the top of the Dakota Group.

Coquina Oil Berthoud State Cores

The Coquina Oil Corporation Berthoud State #3 and #4 wells in the Berthoud oil field north of Fort Collins, Colorado, also are not formally part of the Western Interior Seaway Drilling Project, but geochemical data on samples of the Niobrara and Greenhorn Formations from cores from these wells are presented by Dean and Arthur. The wells are located in Section 16, T9N, R69W, Larimer County, Colorado. Total depth (TD) was 3500 feet (1067 meters). Ground level elevation was 5019 feet (1530 meters).

Princeton University PU79 Core

A core of the Greenhorn Formation was collected by Al Fischer, then at Princeton University near the Pueblo Reservoir, Pueblo County, Colorado. Geochemical data on samples from this core are presented by Dean and Arthur.

Leckie Outcrop Data

Data are presented by Leckie et al. on abundances of planktic and benthic foraminifera, and percentages of clay minerals in samples of Mancos Shale and the age-equivalent Bridge Creek Limestone Member of the Greenhorn Formation from outcrop sections at Lohali Point, northeastern Arizona, Mesa Verde National Park, southwestern Colorado, and Rock Canyon near Pueblo, southeastern Colorado.

The geographic region covered includes western Kansas, eastern Colorado, southwestern Colorado, northeastern Arizona, southeastern Utah

The time period covered by the data files includes 98 Ma to 84 Ma (Late Albian to Santonian Stages of the Cretaceous Period).

The following is a list of all files included in this SEPM data set, all files are located at:

www.ngdc.noaa.gov/mgg/sepm/archive/dean1998_01

• dean1998_01.txt
• dean1998_01.methods.txt
• berthoud.readme.txt
• bounds.amoco.data.txt
• bounds.c_o.isotope.txt
• bounds.carbons.txt
• bounds.gamma.txt
• bounds.icp_xrf.txt
• bounds.nannos.br.ck.txt
• bounds.nannos.niob.txt
• bounds.readme.txt
• bounds.rock_eval.txt
• bounds.scott_et_al.txt
• bst3.c_oisos.txt
• bst3.icp.txt
• bst4.carbons.txt
• bst4.icp.txt
• bst4.rock_eval.txt
• escalante.20_ft.icp.txt
• escalante.20_ft.org.txt
• escalante.carbons.txt
• escalante.isotopes.txt
• escalante.logs.txt
• escalante.readme.txt
• filelist.txt
• leckie.readme.txt
• lohali.forams_clay.txt
• m.verde.forams_clay.txt
• portland.carbons_isotopes.txt
• portland.carlile.carbons.txt
• portland.logs.txt
• portland.nannos.br.ck.txt
• portland.nannos.niob.txt
• portland.readme.txt
• pu79.readme.txt
• pu79carbons.txt
• pu79geochem.txt
• pu79rock_eval.txt
• roccyn.forams_clay.txt

Data were contributed to the SEPM on-line data archive by: Walter E. Dean, U.S. Geological Survey, Denver