The purpose of the Harrisburg Area Geological Society (HAGS) is to stimulate geologic thought, advance and disseminate geologic knowledge, and provide fellowship amongst area individuals interested in earth sciences. Monthly meetings present a realm of geologic topics, ranging from tectonics, coal, carbonate groundwater geochemistry, geomorphology, engineering geophysics, and ore mineralogy. Field trips allow members to visit geologic sites within and beyond Pennsylvania. All events are open to the public and free unless otherwise stated. 


Meetings are held on Zoom at 6:30 PM on the second Thursday of the month, except summer months. Please email the HAGS secretary to be added to the email list and with any questions.


Kent Littlefield


Bill Bruck


Mike Meyer


Amy Randolph


Applied Paleontology

Presented by:  Dr. Charles E. Miller, Jr.


Meeting Date:  Thursday, February 10, 2022

Meeting Time:  6:30 - 7:30 p.m.

Meeting Location:  Zoom

RSVP:  Email the HAGS secretary by noonish on the day of the meeting to RSVP and for Zoom meeting details. 

Presentation Summary: This presentation discusses selected fossil localities and fossil scenarios.  Examples of applied paleontology are given.  Several examples from the talk are mentioned.  Fossils provided the first clue that the length of Earth’s day and the number of days in a year have varied through geologic time.  Implications of this seminal observation will be discussed.  In WWII, fossils were used in forensic geology as part of the war effort.  Of the many different ichnofossils in paleontology, probably the best known are dinosaur trackways.  Two trackway sites will be discussed, emphasizing how they are useful in determining dinosaur social behavior.  A useful “tool” in paleontology is fossil diversity.  Three fossil sites – the Chesapeake and Delaware Canal, the Winfield Quarry in central Pennsylvania, and the State College by-pass – illustrate using fossil diversity.  A review of Cretaceous sites from Kansas to Utah introduces biostratigraphic and lithostratigraphic facies changes.  In the Cambrian Warrior Formation at State College, stromatolites are useful in determining stratigraphic up, as well as making inferences regarding several paleoenvironmental factors, such as water depth, salinity and turbidity.  Numerous other topics will also be discussed.

Speaker Bio: Dr. Miller earned a doctorate in earth science from The Pennsylvania State University.  He is a former earth science teacher, college instructor, petroleum geologist and hydrogeologist.

HAGS Guidebooks are available for download below. To purchase a hardcopy guidebook, contact the HAGS secretary.

Annual Field Trips

1st Annual Field Trip‐ Geology in the South Mountain area, Pennsylvania, Noel Potter, Jr., editor, April 24, 1982, Reprinted 1992. 37 p.

2nd Annual Field Trip‐ Geology along the Susquehanna River, south‐central Pennsylvania, J. Ronald Mowery, editor, April 16, 1983, 55 p.

3rd Annual Field Trip‐ Stratigraphy, structural style, and economic geology of the York‐Hanover Valley, G. Robert Ganis and David Hopkins, April 28,1984, 51 p.

4th Annual Field Trip‐ Pennsylvania’s polygenetic landscape, William D. Sevon, April 27, 1985, Reprinted 1992, 55 p.

5th Annual Field Trip‐ Selected geology of Dauphin and Northumberland Counties, Pennsylvania, by W. D. Sevon, W. E. Edmunds, G. R. Ganis, and J. P. Wilshusen, May 17, 1986, 22 p.

6th Annual Field Trip‐ Lower Jurassic diabase and the Battle of Gettysburg, D. T. Hoff, J. R. Mowery, and G. R. Ganis, April 25, 1987,17 p. plus appendices. 

7th Annual Field Trip‐ The geology of the Lower Susquehanna River area, a new look at some old answers, Glenn H. Thompson, Jr., editor, May 7,1988, 56 p.

8th Annual Field Trip‐ Karst development and environmental geology in the carbonate rocks of the Lehigh and Lebanon Valleys, William E. Kochanov, April 29, 1989, 33 p.

10th Annual Field Trip‐ The Ridge and Valley Physiographic Province and the East Broad Top Railroad, William D. Sevon, June 1, 1991, 24 p.

11th Annual Field Trip‐ Paleozoic geology of the Paw Paw‐Hancock area of Maryland and West Virginia, Marcus M. Key and Noel Potter, Jr., May 9,1992, 25 p.

12th Annual Field Trip‐ South Mountain and the Triassic in Adams County, Pennsylvania, Raymond Britcher, editor, May 22, 1993, 41 p.

13th Annual Field Trip‐ Geology of the Lebanon Valley and western end of the Reading Prong, Charles Scharnberger, editor, April 23. 1994, 68 p.

14th Annual Field Trip‐ Geology of the Rohrer Quarry and Binkley and Ober Quarry near East Petersburg, Lancaster County, PA, Richard P. Nickelsen, Donald U. Wise, Richard Clouser, April 29, 1995, 27 p.

15th Annual Field Trip‐ Pseudo‐Morainic Topography of the Allentown Area of Eastern Pennsylvania, Duane D. Braun and William E. Kochanov, May 4, 1996, 28 p.

16th Annual Field Trip‐ Notes on the Hamburg Klippe: biostratigraphy, ash layers, olistostromes, and “exotics,” G. Robert Ganis, April 26, 1997, 52 p.

17th Annual Field Trip‐ Geomorphology in the Northern Cumberland Valley, PA, including the Carlisle Deluge of 1779, Noel Potter, Jr., Donald Hartman, and Helen Delano, April 18, 1998, 49 p.

18th Annual Field Trip‐ The Cove Syncline by canoe, William M. Roman and Michael A. Knight, May 15, 1999, 16 p. plus maps, Out of Print

19th Annual Field Trip‐ Geology of the Kishacoquillas Valley and vicinity, Mifflin County, Pennsylvania, Michael A. Knight and William M. Roman, May 20, 2000, 18 p. plus maps and sections.

20th Annual Field Trip‐ Geology and Geomorphology of the South Mountain Area, Cumberland and Franklin Counties, Pennsylvania, Noel Potter, Jr., and William D. Sevon, May 14, 2011, 64 p.

21st Annual Field Trip‐ Shermans Creek from Dellville to Duncannon, Perry County, Pennsylvania, William Roman, May 12, 2012, 48 pages, color.

22nd Annual Field Trip‐ Some geological aspects of the north side of the Cumberland Valley in Cumberland County, PA, Bill Sevon, May 4, 2013, 33 pages, large font, color photos.


No formal guidebooks were prepared for the 9th (1990) and 14th (1995) Field Trips. The 2001 trip was a repeat of the 2000 trip.

Other Field Trips

In cooperation with the 20th annual Binghamton Geomorphology Symposium at Dickinson College‐ The rivers and valleys of Pennsylvania, then and now, by William D. Sevon, October 20, 1989, 59 p.

Anthracite Region Field Trip‐ Harrisburg Area Geological Society Field Trip Guidebook Anthracite Region, James E. Baxter and Keith Brady, May 2002, 24 p.

Halloween Limestone Adventure‐ Limestones of Snyder and Centre Counties, PA, Bill Kochanov, Rose-Anna Behr, and Bill Roman, October 22, 2011 May 2002, 25 p.