Halcon Resources – Houston, TX                                                                                 2013-2016
Performed Exploration project evaluations for potential acquisitions/divestitures on full time contract basis.  Detailed research to fully evaluate each prospect, e.g., well tests, core data, Geological & Geophysical input studies, leasing constraints, offset production, “analogy well sets/data” and groundwork O&G industry networking.  Made routine project progress and/or completed project presentations to Management for prospect buy and sell decisions.

Petroskills– Houston, TX                                                                                              2012-2016
Concurrently with my Halcon contract, I also developed and taught industry courses with Petroskills.  The primary courses are customized versions of “Cased Hole Evaluation” and “Production Logging”.

SELF EMPLOYED– Houston, TX                                                                                    2012-2013
Formed S-Corp and did Petrophysical evaluations for selective Texas based Independent O&G Companies.

EP Energy (Formerly Coastal O&G, El Paso E&P Company) – Houston, TX       1999-2012
(Note: El Paso E&P bought Coastal O&G in 2001, and subsequently became EP Energy following a spin-off from the 5/31/2012 Kinder Morgan purchase.) 

Senior Staff Petrophysicist
Performed prospect evaluations for all international, domestic, offshore and Non-Conventional activity, including field studies, brown fields, acquisitions and divestitures (including Southeast US prospects).

  • In 1999, I introduced the iCenter concept (3-D Visualization Room) to Management which was subsequently accepted and contracted for the complete package.  I used the iCenter to host team meetings with the integrated disciplines for drilling, completing and general study purposes. A typical example was directing “real time” drilling an offshore well into a very restricted window assuring ultimate target landing and avoiding complicated pressure hazards.
  • Additionally, I used “subsets” of the iCenter to guide frac teams in smaller specialized visualization rooms that allowed "live" interaction before, during and post frac jobs. This greatly improved results during and following complex frac jobs by preventing screen-outs and managing zone diversions on the fly.
  • I also used the iCenter for training meetings and frequently hosted Petrophysical evaluation presentations as well as open and cased hole training.  I brought in many industry experts on a quarterly basis to introduce new technological services that served to improve success rates and address problems with insufficient solutions, e.g., micro-fracture technology, improved cement evaluations, Production Logging, Geochemistry and Mass Spectroscopy.
  • In 2006, I shifted with the Corporate focus on Unconventional Shale Plays and became the Company’s internal Unconventional Play Petrophysical “expert” for both new well evaluations and completions guidance, e.g., Geosteering advances, micro-fracture analyses, Image Interpretations, Acoustic applications, Micro-Seismic analyses, Rock Mechanics, Mass Spectroscopy, Fluid Inclusion and other special evaluations to successfully drill (horizontally) and enhance production performance.  This resulted in increased penetration drilling rate, better target placement and improved completion designs.

Schlumberger – Houston, TX                                                                                        1963-1999
Sales Development Engineer
Began employment as Field Engineer in 1963 and held various Field positions domestically and Internationally until 1969 when promoted to Special Field Engineering assignments, such as Nuclear Magnetic Logging development.  Promoted to Sales Engineer in 1970 which initiated a career in Sales and Marketing from that point forward.

As Sales Engineer and later as Sales Manager, marketed and sold all Schlumberger products, building growth markets and providing technical assistance for client base.  Made frequent client presentations as well as teaching frequent educational seminars.

  • Created cased-hole evaluation services market primarily with Pulsed Neutron and Spectral analyses for South Texas area beginning in 1972. Increased revenues by 300% over next two years.
  • Provided R&E input for Pulsed Neutron and Spectral Measurement tools development.
  • Continued market development into East Texas and increased revenues by 200% in declining market over next 5 years.
  • Promoted to Sales Manager for South Texas during the mid-1980's downturn. Added new services such as well testing services and grew Schlumberger's market share by over 200% during these downturn years.
  • Originated integrated services packages for client projects, such as drilling, mud programs, logging, well testing and completions.
  • Earned "Outstanding Sales Manager" Award in 1989.
  • Relocated to Houston and moved assigned clients to number 2 spot from number 25.


MBA – Texas A&M University at Corpus Christi, TX                                                                 1996
BS, Petroleum Engineering – Missouri University of Science and Technology                          1960
Also completed approximately 15 hours for MS, Petroleum Engineering before being called in to US Armed Services.


  • Software:  PowerLog, Prizm (GeoGraphix), Interactive Petrophysics, Neural Networks and GAMLS (Geologic Analysis for Maximum Likelihood).  Have used demo packages for Geolog, Techlog and HDS (Hydrocarbon Data Systems).
  • Working knowledge of advanced well logging services, including LWD (Logging While Drilling) and associated services, e.g., pressure testing, coring and perforating.
  • Skilled in new technology available for unconventional resources, e.g., Mass Spectroscopy, Fluid Inclusion, specialized array sonic analyses, micro-seismic analyses, nuclear magnetic applications, fracture identification tools & new lithology identification tools.
  • Advanced experience with completion evaluations using pulsed neutron technology, spectral analyses, production logging, cement and casing evaluation and completion design for tight gas and unconventional horizontal oil wells.


Registered Professional Engineer, State of Texas


Annual attendance of Professional Society Technical Symposiums, e.g., SPE, SPWLA, AAPG, Urtec, NAPE.
A list of all individual industry personal training seminars/courses attended is available on request.


Executive Board, SPE, 1990.
Board of Directors, SPE, 1986-1990.
Several terms as local President, VP and Treasurer for SPWLA in Corpus Christi and Houston from 1965 to present.
President, Corpus Christi Geological Society, 1996
Director, South Texas Energy & Development, Texas A&M, 1995-1997.
Director, Schlumberger Employees Credit Union, 1989-1998.
Member AAPG, SPE and SPWLA.


Latest publication:
SPE Paper 160149, “Production Decline Analysis of Horizontal Wells Intersecting Multiple Transverse Vertical Hydraulic Fractures in Low-Permeability Shale Reservoirs”, by Bobby D. Poe, Jr, Herman Vacca, Art Benjamin and Keith Atwood, SPE Annual Technical Conference and Exhibition, San Antonio, Texas, October 8-10, 2012.
A list of all other publications is available on request.


SPE Legion of Honor, 2007
Distinguished Service Award, SPE, 1991
Regional Service Award, SPE, 1992
Six "Wildcatter" Awards, Schlumberger
Outstanding Sales Manager Award, Schlumberger, 1989


1st Lt, US Army, Mannheim/Sandhofen, Germany 1961-63.
Managed petroleum storage and testing laboratory for US 7th Army, Europe.


Local Houston Civic and Charity Organizations

Petroleum Engineering and Petrophysical background with extensive conventional/non-conventional global experience including open and cased hole formation evaluation, specializing in new technology applications. Especially adept in working with teams to integrate formation evaluation results with local and regional projects such as the Eagleford, Wolfberry, DJ Basin and others. Dedicated to total integration concept analyses in search for commercial new, old and bypassed pay. Comfortable with frequent presentations, educating, tutoring, mentoring and networking.

Herman Vacca


Expertise Includes:

  • Advanced Log Interpretation
  • Completion Operations & Evaluations
  • Conventional & Unconventional Resources
  • Education, Tutoring & Mentoring
  • Geosciences Integration
  • Customer Service
  • Creative and Technical Writing