Our Management Team

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Michael Oestmann

President & Chief Executive Officer

Mr. Oestmann has over 37 years of experience in all aspects of the oil and gas business, with a particular focus on company start-ups, exploration, asset management and development. Mr. Oestmann has experience in numerous geologic basins with primary focus in the Permian Basin and has a consistent record of increasing production in existing fields, exploration success and company development and sale. Mr. Oestmann began his career with Exxon Co. USA in 1982 after graduating from Rice University with a bachelor’s degree in geology with a geophysics option. He worked 15 years with Exxon, 7 years with Titan/Pure Resources/Unocal, 2 years with Celero/Whiting, and 1 year with Lothian Oil in various exploration, development and senior management positions. In 2007 he co-founded Piedra Resources with private equity partners. Piedra sold its assets in 2011 for over $120 million.  Mr. Oestmann began Tall City Exploration in May of 2012 with a $200 Million equity commitment from Denham Capital. Tall City completed the sale of its assets in 2015 for a total of $1.2B.  He is a 35 year member of the AAPG and SEG, member of the PBGS (having served as President) WTGS and SPE. He is a certified geologist with the Texas Board of Professional Geoscientists and the DPA of the AAPG, and serves as an elder at Westway Church of Christ. He and Cathy, his wife of 34 years, live in Midland, Texas.

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Michael Marziani

Executive Vice President & Chief Financial Officer

Prior to joining Tall City, Mr. Marziani spent five years as an investment banker and Principal with Greenhill & Co., a boutique M&A advisory firm. He helped to found Greenhill’s Houston office and advised on a number corporate energy M&A transactions, most notably: the $4.8 billion Devon Energy/Crosstex midstream combination in 2013, Linn Energy’s $4.9 billion acquisition of Berry Petroleum in 2013, Superior Energy Services’ $3.2 billion acquisition of Complete Production Services in 2011 and BJ Services Company’s $7.6 billion merger with Baker Hughes in 2009. Prior to his time at Greenhill, Mr. Marziani was a Vice President with Merrill Lynch and spent over five years in the Global Energy & Power investment banking team in Houston. While at Merrill Lynch, he was a member of transaction teams that completed over $6.5 billion in energy-focused M&A advisory transactions and over $13.5 billion in capital markets underwriting transactions. Prior to joining Merrill Lynch, he worked in a variety of petroleum and reservoir engineering roles for BP in Houston. Mike holds a B.S. in Mechanical Engineering from Rice University and received an M.B.A. with high honors from the McCombs School of Business at the University of Texas at Austin.

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Dennis Kruse

Senior VP Drilling

Mr. Kruse has worked in various drilling and operations positions since receiving a BS degree in Petroleum Engineering in 1982 from Texas Tech University. He spent the first 15 years of his career with Gulf Oil Company and Chevron USA in the Permian Basin. Dennis worked as Drilling Foreman, Drilling Engineer, Superintendent, and Engineering Advisor across numerous areas. He gained experience while drilling deep Delaware Basin gas wells, underpressured (air) drilling environments, large infill waterflood projects, and numerous horizontal wells. Mr. Kruse formed Drillmark Consulting, an Engineering and Wellsite Consulting firm in 1997. During the period from 1997 – 2004, he managed numerous consultants and projects for various companies. Projects included wells in Texas, New Mexico, Lousiana, and Oklahoma. In 2004, he merged the firm with EPI Consultants, a subsidiary of Cudd Pressure Control, and served as VP/General Manager of that organization. From 2006 until joining Tall City Exploration, Mr. Kruse has been an independent Project Manager/Operator/Partner in several areas of Texas, including Wolfberry, Barnett Shale, 3rd Bone Springs and other plays. Dennis is a member of SPE and a founding member of the AADE in the Permian Basin.

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Angela Staples

Senior VP Land & General Counsel

Angela Staples has 20 years of experience in the oil and gas industry. She graduated from the University of Texas at Austin School of Law in 2003. She is admitted to both the Texas and New Mexico bars, and is board certified in Oil, Gas, and Mineral Law by the Texas Board of Legal Specialization. Angela serves as the General Counsel to the Permian Basin Petroleum Association, which provides legislative and regulatory advice and representation for oil and gas operators in Texas and New Mexico. Angela authors a monthly article for their magazine, PB Oil & Gas, which typically consists of recent case law review and analysis that relates to the oil and gas industry.

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Gary Womack

Senior VP Engineering & Operations

Mr. Womack formerly served as Engineering and Operations Manager of Chi Energy, Inc. He has extensive operational and engineering experience in the Permian, Delaware, and Midcontinent producing basins. He began his engineering career with Oxy USA after graduating from Texas Tech University with a M.S. in Petroleum Engineering. His ten years at Oxy included supervision of various projects in the Permian basin of West Texas and Delaware basin in New Mexico. Mr. Womack left Oxy as an Engineering Advsior in 2002 to join Chi Energy where his focus included acquisition and implementation of drilling and producing projects in Texas and New Mexico.

Matt Lake

Vice President Reservoir Engineering

Matthew Lake joined Tall City Exploration III with over 18 years of experience in the oil and gas industry. Prior to joining Tall City, Mr. Lake served as Vice President of Engineering for Blue Whale Energy North America evaluating acquisition opportunities for international investors, and was notably involved in the acquisition of Tall City Exploration I. Prior to joining Blue Whale in June 2015, Mr. Lake served as Vice President at TPH Partners, LLC, the private equity affiliate of Tudor Pickering Holt & CO., where he was responsible for monitoring the performance of multiple upstream portfolio companies as well as evaluating new investment opportunities in the upstream, midstream and oilfield services sector. Prior to TPH, Lake was with LINN energy from 2009 to 2014 in a variety of roles, including reservoir and production engineering, operations, business development and planning. His last role at LINN served as Engineering Advisor and Asset Team Lead for the Central Permian region, where he oversaw a team of technical professionals responsible for the development of multiple fields. Prior to LINN, Lake was with Merrill Lynch & Co. from 2006 to 2009 where he served as an Analyst and Associate in the Global Energy & Power investment banking group. Lake served in a technical role to the team with responsibilities in A&D and corporate M&A, ultimately involved in over $11 billion of transactions. Prior to Merrill Lynch, Lake worked with TRC Consultants, LC from 2000 to 2005 and had a consulting role at Ryder Scott & Co. providing engineering and economic consulting services during the second half of 2005. Lake graduated from the University of Texas at Austin with a BS in Geosystems Engineering and Hydrogeology in May 2000.


Thomas Fekete

Vice President Geoscience

Prior to joining Tall City Exploration III Mr. Fekete spent 18 years as a partner in Jordan-Rubicon Resources, generating and selling drilling deals and prospects in the Permian Basin. He began his geological career with Atlantic Richfield in 1988 after graduating from the University of Wisconsin-Madison with a M.S. in Geology. His 13 years at ARCO included a variety of Exploration, Development and Business Development assignments, mainly focused on the Permian Basin.

Doug Rook

Vice President Business Development

Doug Rook joined Tall City Exploration III in 2019 with over 21 years of industry experience. Mr. Rook has been involved in over $4 billion of acquisitions in his career and has managed over 650,000 acres of lease acquisitions. Most recently, Mr. Rook served as Manager of Business Development for Hilcorp Energy Company. From 2015 to 2018, Mr. Rook served as Vice President of Land & Business Development for Blue Whale Energy where he was involved in over $1.5 billion of acquisitions, most notably was the acquisition of Tall City Exploration I’s assets in Howard County. Prior to joining Blue Whale in 2015, Mr. Rook was a Principal and Vice President of Land & Business Development for Kraken Oil & Gas LLC I where they compiled over 120,000 acres via organic leasing, farmins and other strategic deal structures in the Williston Basin. Prior to joining Kraken in 2012, Mr. Rook was with Rosetta Resources and served as Manager, Land & Asset Business Development where he was responsible for managing the company wide land effort in the Eagleford and Rocky Mountain regions which included operations, leasing efforts and asset business development across the Lower 48. From 1997 until joining Rosetta, Mr. Rook served in various Land, Business Development and Energy Trading roles with Linn Energy, Burlington Resources / ConocoPhillips, TXU Energy, Duke Energy and Sonat Exploration. Mr. Rook earned a BBA in Petroleum Land Management / Marketing from Texas Tech University and an MBA from Tulane University. Mr. Rook is a member of the AAPL, ADAM Permian, ADAM Rockies and serves as an Advisor for ADAM Houston.

Tall City Exploration III VP Team

Tall City Exploration III Team