Skip Navigation

Geological Log Analysis

Prev Page--Resistivity Image Logging


The most common use of logs by geologists is for correlation: picking formation tops. Sadly, most geologists in industry have only a rudimentary knowledge of log properties, most of which they gained piecemeal from experience with interpreting logs on work projects. Hopefully, some of the examples in the lessons of this class have demonstrated the wealth of geological information in modern logs, which contuinues to expand with each new generation of logging measurements.

The practice of reading logs is often vaguely termed "log interpretation" or, if numbers are read and crunched with simple equations, then the results are termed "log analysis." In 1950, Gus Archie of the Shell Oil Company introduced the concept of "petrophysics" which is now the term most widely used for log and core analysis and interpretation.

At many universities (including KU), log analysis is a requirement for petroleum engineering undergraduates because logs are a fundamental information source on reservoir properties of porosity, fluid saturation, and permeability. Courses involving logs are optional for geology students but are worthy of consideration because petrophysicists with a geological background are currently in high demand in industry, both to work with traditional reservoir rocks and emerging organic mudstone plays.

The professional society for those who are interested in petrophysics is the SPWLA (Society of Petrophysicists and Well Log Analysts) located at


Adams, J.A.S., and Weaver, C.E., 1958, Thorium to uranium ratios as indicators of sedimentary processes, Example of concept of geochemical facies: AAPG Bulletin, v. 42, p. 387-430.

Algeo, T.J., and Maynard, J.B., 2004, Trace element behavior and redox facies analysis of core shales of Upper Pennsylvanian Kansas-type cyclothems: Chem. Geol., v. 206, p. 289-318.

Benison, K.C., 2006, A Martian analog in Kansas: Comparing Martian strata with Permian acid saline lake deposits: Geology v. 34, no. 5, p. 385-388.

Berendsen, P., and others, 1988, Texaco Poersch #1, Washington County, Kansas—Preliminary geologic report of the pre-Phanerozoic rocks: Kansas Geological Survey, Open File Report 88-22, 116 p. [available online]

Brown, S.L., 1967, Stratigraphy and depositional environment of the Elgin Sandstone (Pennsylvanian) in south-central Kansas: Kansas Geological Survey, Bull. 187, Part 3, 9 p. [available online]

Buatois, L.A., Mangano, G., and Carr, T.R., 1999, Sedimentology and Ichnology of Paleozoic Estuarine and Shoreface Reservoirs, Morrow Sandstone, Lower Pennsylvanian of South-west Kansas, USA: Kansas Geological Survey, Bull. 243, part 1. [available online]

Chung, G. S., and Swart, P. K., 1990, The concentration of uranium in freshwater vadose and phreatic cements in a Holocene ooid cay: a method of identifying ancient water tables. Journal of Sedimentary Research, v. 60, no. 5, p. 735-746.

DeVries, A. A., 2005, Sequence stratigraphy and micro-image analysis of the upper Morrow sandstone in the Mustang East Field, Morton County, Kansas, MS Thesis, Oklahoma State University.

Diaz, H.G., and others, 2013, Evaluating the impact of mineralogy on reservoir quality and completion quality of organic shale plays, AAPG Search and Discovery Article #41221. [available online]

Doveton, J.H., Merriam, D.F., and Olea, R.A., 2003, Spatial and temporal relations of Upper Pennsylvanian black shales in Kansas (abs.): AAPG Midcontinent Section Meeting, Tulsa, p. 30.

Fertl, W.H., Stapp, W.L., Vaello, D.B., and Vercellino, W.C., 1980, Spectral gamma-ray logging in the Texas Austin Chalk Trend: Jour. Petr. Tech., v. 32, p. 481-488.

Glenister, L.M., and Kauffman, E.G., 1985, High resolution stratigraphy and depositional history of the Greenhorn regressive hemicyclothem, Rock Canyon Anticline, Pueblo, Colorado: SEPM Field Trip Guidebook No. 4, p. 170-183.

Gromet, L.P., Dymek, R.F., Haskin, L.A., and Korotev, R.L., 1984, The North American Shale Composite, its compilation, major, and trace element characteristics: Geochim. Cosmochim. Acta, v. 48, no. 12, p. 2469-2482.

Hattin, D.E., and Siemers, C.T., 1987, Guidebook: Upper Cretaceous stratigraphy and depositional environments of western Kansas: Kansas Geological Survey, Guidebook Series No. 3, 55 pp. [available online]

Heckel, P.H., Brady, L.L., Ebanks, W.J., Jr., and Pabian, R.K., 1979, Guidebook, Pennsylvanian cyclic platform deposits in Kansas and Nebraska: Kansas Geological Survey, Guidebook Series, no. 4, 79 p. [available online]

Hester, T.C., and others, 1990, Log-derived regional source-rock characteristics of the Woodford Shale, Anadarko Basin, Oklahoma: U.S. Geological Survey, Bull. 1866-D, 38 pp. [available online]

Luchtel, K. L., 1999, Sequence stratigraphy and reservoir analysis of the upper Kearny Formation (Morrowan Series, Lower Pennsylvanian System) within three Kansas fields: Unpubl. MS thesis, University of Kansas, 149 p.

Luczaj, J.A. and Goldstein, R.H., 2000, Diagenesis of the lower Permian Krider Member, southwest Kansas, USA: Fluid-inclusion, U-Pb, and fission-track evidence for reflux dolomitization during latest Permian time. Journal of Sedimentary Research, v. 70, no. 3, p. 762-773.

Merriam, D.F., 1963, The Geologic History of Kansas: Kansas Geological Survey, Bull. 162, 317 pp. [available online]

Newell, K.D., and others, 2007. H2-rich and Hydrocarbon Gas Recovered in a Deep Precambrian well in Northestern Kansas: Natural Resources Research, v. 16, no. 3, p. 277-292.

Plummer, N., and Romary, J.F., 1947, Kansas Clay, Dakota Formation: Kansas Geological Survey, Bull. 67, 241 pp.

Pollastro, R. M., and Scholle, P. A., 1984, Hydrocarbons exploration, development from low-permeability chalks-upper cretaceous Niobrara formation, Rocky Mountains region. Oil Gas Jour., v., 82.

Quinby-Hunt, M.S., Wilde, P., Orth, C.J., and Berry, W.B.N., 1989, Elemental geochemistry of black shales--statistical comparison of low-calcic shales with other shales: U.S. Geological Survey, Circular 1037, p. 8-15. [available online]

Rawson, R.R., 1980, Uranium in the Jurassic Todilto Limestone of New Mexico--an example of a sabkha-like deposit: SEPM Short Course Notes p. 127-147.

Ruffel, A.H., Worden, R.H., and Evans, R., 2003, Paleoclimate controls on spectral gamma-ray radiation from sandstones: Int. Assoc. Sed. Spec. Publ. 34, p. 93-108.

Spears, R.W., and Jackson, S.L., 2009, Development of a predictive tool for estimating well performance in horizontal shale gas wells in the Barnett Shale, North Texas, USA: Petrophysics, v. 50, no. 1, p. 19-31.

Walters, R.F., 1953, Oil production from fractured Precambrian basement rocks in central Kansas: AAPG Bull., v. 37, p. 300 -313.

Watney, W.L., 1985, Origin of Four Upper Pennsylvanian (Missourian) Cyclothems in the Subsurface of Western Kansas Unpubl. PhD dissertation, University of Kansas, 506 pp.

Wilke, N.A., 2000, Sequence Stratigraphy of the Bethany Falls Limestone in Eastern Kansas and Western Missouri: unpubl. Master's Thesis, University of Kansas, 78 pp.

Zelt, F.B., Paleoceanographic events and lithologic/geochemical facies of the Greenhorn marine cycle (Upper Cretaceous) examined using natural gamma-ray spectrometry: SEPM Field Trip Guidebook No. 4, p. 49-59.

Prev Page--Resistivity Image Logging

Kansas Geological Survey
Updated July 31, 2017.
Comments to
The URL for this page is