National and Global Petroleum Assessment

Assessment of Continuous Oil and Gas Resources in the 

Pannonian Basin Province, Hungary, 2016

Using a geology-based assessment methodology, the U.S. Geological Survey estimated mean undiscovered, technically recoverable 

continuous resources of 119 million barrels of oil and 944 billion cubic feet of gas in the Hungarian part of the Pannonian Basin Province.

Introduction

The U.S. Geological Survey (USGS) completed 

an assessment of undiscovered, technically recoverable continuous oil and gas resources within the 

Hungarian part of the Pannonian Basin Province 

(fig. 1). The Neogene Pannonian Basin Province 

is a structurally complex region surrounded by the 

eastern Alps, west Carpathians, Munții Apuseni, 

outer Carpathians, south Carpathians, and Dinaric 

Alps fold belts (Royden, 1988; Dolton, 2006; Tari 

and Horváth, 2006; Matenco and Radivojević, 2012). 

Badics and Veto (2012) summarized all of the pertinent geologic and geochemical data on potential 

continuous (shale oil and shale gas) reservoirs in the 

Hungarian part of the Pannonian Basin Province. 

Badics and Veto (2012) concluded that the most 

viable continuous reservoirs are within the Triassic 

Kossen Shale, the Lower Jurassic Mecsek Unit, and 

the lower Oligocene Tard Shale. The purpose of this 

study is to estimate potential volumes of recoverable 

continuous oil and gas resources within these three 

stratigraphic intervals.

Total Petroleum Systems and Assessment Units

For the Pannonian Basin Province, the USGS 

defined a Triassic Kossen Total Petroleum System 

(TPS) with the Triassic Kossen Shale Oil Assessment 

Unit (AU) and the Triassic Kossen Shale Gas AU, a 

Lower Jurassic TPS with the Lower Jurassic Mecsek 

Tight Gas AU, and a Lower Oligocene TPS with the 

Lower Oligocene Tard Shale Oil AU and the Lower 

Oligocene Tard Shale Gas AU within this TPS (fig. 1). 

The areas of these AUs reflect the mapping of Badics 

and Veto (2012).

The geologic model for the Triassic Kossen 

Shale Oil AU and the Triassic Kossen Shale Gas AU 

is for some portion of oil and gas generated from 

organic-rich shales (as much as 19 weight percent total 

organic carbon; Clayton and Koncz, 1994; Badics and 

Veto, 2012) to have been retained within the shales. 

The geologic model for the Lower Jurassic Mecsek 

Unit is for gas generated from coals and carbonaceous 

Figure 1.  Location of the Pannonian Basin Province and the five continuous

assessment units (AUs) defined in this study.

shales to have migrated locally into tight reservoirs, forming a tight-gas 

accumulation. The geologic model for the Lower Oligocene Tard Shale Oil 

AU and Lower Oligocene Tard Shale Gas AU is for some portion of the 

generated oil and gas to have been retained within Tard shales.

Assessment input data for five continuous assessment units are shown in 

table 1. Well drainage areas, estimated ultimate recoveries, and success ratios 

are taken from U.S. shale-oil, shale-gas, and tight-gas analogs.

BRATISLAVA

VIENNA

BUDAPEST

16° 17° 18° 19° 20° 21° 22° 23°

49°

48°

47°

46°

45°

44°

SERBIA

CROATIA

HUNGARY

AUSTRIA

SLOVAKIA

ROMANIA

BOSNIA AND

HERZEGOVINA

CZECH REPUBLIC

POLAND

UKRAINE

ADRIATIC

SEA

SLOVENIA

EXPLANATION

Pannonian Basin Province boundary

Triassic Kossen Shale Oil AU

Triassic Kossen Shale Gas AU

Lower Jurassic Mecsek Tight Gas AU

Lower Oligocene Tard Shale Oil AU

Lower Oligocene Tard Shale Gas AU

Source: U.S. Department of the Interior National Park Service

Carpathians Carpathians

Munții

Apuseni

Carpathians

Dinaric Alps

Alps

0 100 KILOMETERS 50

0 50 100 MILES

HUN

SVK

SRBBIH

HRV

BGR

POL

CZE

AUT

SVN

UKR

ROU

Map

area

U.S. Department of the Interior

U.S. Geological Survey

Fact Sheet 2017–3033

June 2017
Undiscovered Resources Summary

The USGS quantitatively assessed undiscovered, technically recoverable continuous oil and gas resources within five AUs in 

the Hungarian part of the Pannonian Basin Province (table 2). The total means for continuous resources are 119 million barrels of 

oil (MMBO) with an F95–F5 range from 0 to 299 MMBO, 944 billion cubic feet of gas (BCFG) with an F95–F5 range from 0 to 

3,239 BCFG, and 13 million barrels of natural gas liquids (MMBNGL) with an F95–F5 range from 0 to 45 MMBNGL.

Table 1.  Key assessment input data for five continuous assessment units in the Hungarian part of the Pannonian Basin Province.

[%, percent; EUR, estimated ultimate recovery per well; MMBO, million barrels of oil; BCFG, billion cubic feet of gas. Well drainage areas, EURs, and well success ratios are 

from U.S. shale-oil, shale-gas, and tight-gas analogs. The average EUR input is the minimum, median, maximum, and calculated mean. Shading indicates not applicable]

Assessment input data—

Continuous assessment units (AUs)

Triassic Kossen Shale Oil AU Triassic Kossen Shale Gas AU

Minimum Mode Maximum Calculated mean Minimum Mode Maximum Calculated mean

Potential production area of AU (acres) 480 60,000 120,000 60,160 480 50,000 100,000 50,160

Average drainage area of wells (acres) 40 80 120 80 80 120 160 120

Success ratios (%) 10 50 90 50 10 50 90 50

Average EUR (MMBO, oil; BCFG, gas) 0.04 0.08 0.2 0.086 0.1 0.3 0.7 0.319

AU probability 0.9 0.9

Assessment input data—

Continuous assessment units (AUs)

Lower Jurassic Mecsek Tight Gas AU Lower Oligocene Tard Shale Oil AU

Minimum Mode Maximum Calculated mean Minimum Mode Maximum Calculated mean

Potential production area of AU (acres) 480 1,300,000 4,000,000 1,766,827 480 408,000 816,000 408,160

Average drainage area of wells (acres) 40 80 120 80 40 80 120 80

Success ratios (%) 10 50 90 50 10 50 90 50

Average EUR (BCFG, gas; MMBO, oil) 0.04 0.08 0.4 0.098 0.02 0.04 0.1 0.043

AU probability 0.5 0.8

Assessment input data—

Continuous assessment units (AUs)

Lower Oligocene Tard Shale Gas AU

Minimum Mode Maximum Calculated mean

Potential production area of AU (acres) 480 255,000 509,000 254,827

Average drainage area of wells (acres) 80 120 160 120

Success ratios (%) 10 50 90 50

Average EUR (BCFG, gas) 0.04 0.1 0.8 0.138

AU probability 0.8

Table 2.  Assessment results for five continuous assessment units in the Hungarian part of the Pannonian Basin Province.

[MMBO, million barrels of oil; BCFG, billion cubic feet of gas; NGL, natural gas liquids; MMBNGL, million barrels of natural gas liquids. Results shown are fully 

risked estimates. For gas accumulations, all liquids are included in the NGL category. F95 represents a 95-percent chance of at least the amount tabulated; other fractiles 

are defined similarly. Fractiles are additive under the assumption of perfect positive correlation. Shading indicates not applicable]

Total petroleum system and

assessment units (AUs)

AU

probability

Accumulation

type

Total undiscovered resources

Oil (MMBO) Gas (BCFG) NGL (MMBNGL)

F95 F50 F5 Mean F95 F50 F5 Mean F95 F50 F5 Mean

Triassic Kossen Total Petroleum System

Triassic Kossen Shale Oil AU 0.9 Oil 0 26 70 30 0 51 145 59 0 1 3 1

Triassic Kossen Shale Gas AU 0.9 Gas 0 54 140 60 0 1 3 1

Lower Jurassic Total Petroleum System

Lower Jurassic Mecsek Tight Gas AU 0.5 Gas 0 0 2,112 533 0 0 22 5

Lower Oligocene Total Petroleum System

Lower Oligocene Tard Shale Oil AU 0.8 Oil 0 79 229 89 0 152 476 178 0 3 10 4

Lower Oligocene Tard Shale Gas AU 0.8 Gas 0 79 366 114 0 2 7 2

Total undiscovered continuous resources 0 105 299 119 0 336 3,239 944 0 7 45 13

References Cited

Badics, Balázs, and Veto, István, 2012, Source rocks and petroleum systems in the Hungarian part of the Pannonian Basin—The potential for shale gas and shale oil plays: 

Marine and Petroleum Geology, v. 31, no. 1, p. 53–69.

Clayton, J.L., and Koncz, Istvan, 1994, Petroleum geochemistry of the Zala Basin, Hungary: American Association of Petroleum Geologists Bulletin, v. 78, no. 1, p. 1–22.

Dolton, G.L., 2006, Pannonian Basin Province, Central Europe (Province 4808)—Petroleum geology, total petroleum systems, and petroleum resource assessment: U.S. Geological Survey Bulletin 2204–B, 47 p.

Matenco, L.C., and Radivojević, D., 2012, On the formation and evolution of the Pannonian basin—Constraints derived from the structure of the junction area between the 

Carpathians and Dinarides: Tectonics, v. 31, no. 6, 31 p.

Royden, L.H., 1988, Late Cenozoic tectonics of the Pannonian Basin system, chap. 3 of Royden, L.H., and Horvath, Ferenc, eds., The Pannonian Basin—A study in basin 

evolution: American Association of Petroleum Geologists Memoir No. 45, p. 27–48.

Tari, G.C., and Horváth, Frank, 2006, Alpine evolution and hydrocarbon geology of the Pannonian Basin—An overview, chap. 19 of Golonka, J., and Picha, F.J., eds., The 

Carpathians and their foreland—Geology and hydrocarbon resources: American Association of Petroleum Geologists Memoir No. 84, p. 605–618.

For More Information

Assessment results also are available at the USGS Energy Resources Program website at https://energy.usgs.gov.

Pannonian Basin Province Assessment Team

Christopher J. Schenk, Timothy R. Klett, Phuong A. Le, Michael E. Brownfield, and Heidi M. Leathers-Miller

ISSN 2327-6916 (print) ISSN 2327-6932 (online) https://doi.org/10.3133/fs20173033