Dr. Darrell L. Kramer


Dr. Kramer is an innovative, problem solving geoscientist skilled in multiple disciplines of geology, geophysics and petrophysics. He has over 30 years of experience in the geoscience field, both within the mining and oil and gas industries. Dr. Kramer has worked and managed cross-functional teams in the areas of exploration and development. He is familiar with clastic and carbonate environments in both conventional as wells as resource plays. His background includes positions in research, teaching and mentoring, and has worked both domestically and internationally.


Senior Geoscience Advisor
Ossidiana Energy Holdings, LLC
Sept 2019 – May 2020: 8 months
Greenwood Village, Colorado

Ossidiana Energy is a startup oil and gas company focused on exploration in the Northern DJ Basin, Wyoming. Ossidiana Energy has drilled three exploration strat tests and one horizontal development well.

Responsibilities include: Managing coring and analysis, specialty wire-line logging, geomechanical analysis for stimulation design, geological correlations of the Niobrara interval to identify potential targets, and seismic interpretation to determine structural faulting and stratigraphic traps.

Senior Geoscientist
International Reservoir Technologies, Inc
Jan 1998 – Aug 2019: 21 years 8 months
Denver, Colorado

IRT is a consulting group to the Oil and Gas Industry. IRT specializes in integrated studies from reservoir characterization to reservoir simulation. The company also consults on an individual discipline basis including petrophysics, geophysics, geology, stratigraphy, petroleum and reservoir engineering. Operations are both domestic and international.

Responsibilities include: Management of any projects secured by me from clients. Projects include seismic acquisition design, QC processing and interpretation of data; modeling and interpretation of AVO and AVA data; ranking of prospects using Crystal Ball for uncertainty analysis and implementing core analysis data into petrophysical models. Projects have included legal expert witness for arbitration settlement, mentoring and teaching classes in the geosciences.

Unocal 7 Years, 1 Month

    Senior Geophysicist: Unocal Exploration GOM
    Aug 1997 – Dec 1997: 5 months
    Sugarland, Texas

    Responsibilities: Geophysical lead to interpret 3-D and 2-D seismic data for OCS leases sale, offshore Louisiana and Texas. Additional responsibilities include: Synthetic seismic and AVO modeling for oil and gas exploration as well as monitor operation of wells drilled.

    Senior Geophysicist (Spirit Energy – Subsidiary of Unocal)
    June 1995 – July 1997: 2 years 1 month
    Lafayette, Louisiana

    Spirit Energy was a subsidiary company set up to explore and develop assets for offshore Gulf of Mexico. The company was later re-absorbed into Unocal.

    Responsibilities: Geophysical lead for interpretation of a 3D seismic survey and well planning for the development of 350 BCF gas field, Gulf of Mexico. Exploitation and exploration of surrounding lease blocks. This included, interpretation of 2D seismic data to determine exploration plays and recommendation of lease bids for ‘96 Texas, GOM lease sale. While in this position, I developed a mathematical algorithm for UNOCAL's version of Coherency Cube technology to aid in the identification of faults on 3-D seismic data. A Patient was issued for this technology with David Keller who implemented the algorithm into a computer code.

    Project Geophysicist, Unocal Caribbean Team
    Jan 1993 – May 1995: 2 years 5 months
    Houston, Texas Area and Port of Spain, Trinidad and Tobago

    Responsibilities: Exploration for oil in the Columbus Basin, offshore Eastern Trinidad. Duties include quality control of acquisition and processing an offshore 3-D seismic survey, interpretation of 2-D and 3-D seismic data and integrating geology to recommend drilling locations of a three well exploration program. This led to the discovery of approximately 20 MMbbls OOIP.

    Project Geophysicist, Unocal Potential Fields
    July 1992 – Dec 1992: 0.5 years
    Sugar Land, Texas

    Responsibilities: Participated in a six-month assignment in gravity and magnetics department. Interpreted and inverse modeled gravity and magnetic data to aid in basin analysis offshore Nam Con Son Basin, Vietnam, Falklands Islands, and Greenland.

    Senior Geophysicist, Unocal Research
    April 1991 – June 1992: 1 year 2 months
    Brea, California

    Responsibilities: Worked on a source signature study of shear wave vibrators to determine source and receiver array configuration to eliminate ground roll. Develop and implement multicomponent deconvolution operator. Tested and recommended development of company proprietary prestack depth migration programs that honor anisotropy. Anisotropy and synthetic seismogram models for exploration in Baku, Azerbaijan.

Mobil Oil Canada, Ltd & Dallas Research Lab
May 1984 – July 1988: 4 years 3 months
Calgary, Canada Area

Responsibilities included: QC of seismic data acquisition, including Mobil’s first 3-D seismic survey. Quality controlled processing and interpretation of 2D and 3D seismic data for exploration in the Alberta Basin. Specialty processing of seismic for secondary recovery including, 4D (repeat) seismic surveys to monitor a stream front during tertiary recovery program in heavy oils, Tar Sands, Alberta.

Developed and implemented earth filters (Q- compensation) for synthetic seismograms to better match seismic data. Algorithm was used throughout company. I assisted in the development of an early version of 3-D seismic interpretation programs on PC workstations.

I was a geophysical member of a review team tasked to study unsuccessful drilling programs and recommend new technologies to reduce the risk of dry holes.

I worked in Mobil’s Dallas Research Lab implementing multicomponent VSP processing algorithms.

Geophysical Assistant
AMOK Ltd (Subsiduary of COGEMA) and Saskatchewan Mining Development Company (SMDC)
May 1979 – Sept 1982: Summer Exploration Program

AMOK and SMDC were Canadian companies involved in exploration of Uranium.

Responsibilities: Summer field program for exploration of Uranium by using Radon Detection, Time Domain EM, VLF, Marine Seismic, Induced Polarization, Gravity and EM37 Magnetics. We mapped and delineated multiple targets for a winter drilling program. I worked to delineate the Carswell Structure, at the Cluff Lake Uranium Mine, Northern Saskatchewan.


    Colorado School of Mines
    Ph.D. Geophysics
    1988 – 1991

    Colorado School of Mines
    M.S. Geophysics
    1982 – 1984

    University of Regina
    B.S. (Honors) Physics
    1979 – 1981

    University of Regina
    B.Ed Math & Physical Education
    1975 – 1979


    Seismic Semblance/Discontinuity Method
    Issued October 31, 2000, United States: U.S. Serial No. 6,141,622
    The Semblance Attribute was developed to more reliably detect seismic discontinuities. The semblance attribute of the center point of a seismic volume is calculated from 3D traces within a spatial and time window. The seismic attribute is dependent, at least in part, on the ratio of the square of the sum of the amplitudes of said traces within the window and the sum of the squared amplitudes of said seismic traces over within the window.


    SPE 121878 J. A. Murtha, R. Osorio, and H. H. Perez, ECOPETROL, D. L. Kramer, R. J. Skinner, C. A Williams, International Reservoir Technologies, Inc. Experimental Design: Three Contrasting Projects, Presented at the 2009 SPE Latin American and Caribbean Petroleum Engineering Conference held in Cartagena, Colombia, 31 May . 3 June, 2009.

    SPE 86996-MS Darrell Kramer, David List, Laura Tillman, Keith Jagiello, Tom Gould, International Reservoir Technologies: Seismic and Geological Evidence of Complex "Positive Flower" Structures Along Confining Bends in Strike-slip Faults, Lake Maracaibo, Venezuela. Presented at the SPE Asian Pacific Conference on Integrated Modeling for Asset Management, 29-30 March 2004, Kuala Lumpur, Malaysia.

    Xu, Wenlong, Kramer, D. L., Dooley, Paul, Domingue, Kirby and Vo, D.T., Brazos A-105 D-sand Reservoir Modeling by Integration of Seismic Elastic Inversion Results with Geostatistical Techniques, AAPG Publication: Stochastic Modeling II, edited by T. C. Coburn, J. M. Yarus and R. L. Chambers, January 2006.

    Dunham, J.B., Frankforter, M., Kramer, D.L. and Weihe, J.: .Thin-Skinned Deformation of the Cretaceous and Tertiary Sedimentary Section of Eastern Offshore Trinidad, Second AAPG/SVG International Congress; Caracas Venezuela, Proceedings, p. A13; 1996.

    Weihe, J., Dunham, J. and Kramer, D.L.: 3-D Seismic and Gravity Interpretation of a Fractured Cretaceous Exploration Play.; Offshore Eastern, Trinidad, VII Venezuelan Geophysical Congress, Expanded Abstracts, 94, 274-270; 1994.

    Kramer, D.L. and Davis, T.L.: Multicomponent Vertical Seismic Profiles for Reservoir Characterization; South Casper Creek field, Natrona County, Wyoming, 61st Annual International Meeting, Society of Exploration Geophysicists, Expanded Abstracts, 91, 383-386; 1991.

    Kramer, D.L.: Multicomponent, Multioffset VSP Processing, 61st Annual International Meeting, Society of Exploration Geophysicists, Expanded Abstracts, 91, 38-42; 1991.

    Kramer, D.L. and Davis, T.L.: Multicomponent VSPs For Reservoir Characterization.; South Casper Creek Field, Wyoming, The Leading Edge, 11, no. 9, 31-35; 1991, Sept.

    Kramer, D.L.: TDEM-Seismic Correlation, 54th Annual International Meeting, Society of Exploration Geophysicists, Expanded Abstracts, 84, Session: EM2.7; 1984.


    Numerous presentations to clients, colleagues and at local and international conferences (SEG, CSEG, DGS, SPE)


    Microsoft Office Suite (Word, EXCEL, Power Point, Project, Teams)
    WellCAD - Core Logging Software
    TerraScience.s Terra Station - Petrophysical and Image Software
    Oracle - Crystal Ball
    Halliburton’s Landmark Geoscience Software
    LMKR GeoGraphix Suite of Software
    IHS’s Kingdom Suite of Software


    Society of Exploration Geophysicists (SEG)
    Canadian Society of Exploration Geophysicists (CSEG)
    Denver Geophysical Society (DGS)
    Rocky Mountain Association of Geologists (RMAG)
    American Association of Petroleum Geologists (AAPG)