UKCS License P th Round Traditional Carrizo Oil & Gas, Inc. (operator) 100%

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Block 22/8a Relinquishment Report UKCS License P.1797 26 th Round Traditional Carrizo Oil & Gas, Inc.

1 Block 22/8a Relinquishment Report UKCS License P th Round Traditional Carrizo Oil & Gas, Inc. (operator) 100% March 2015 Estimates, statistics, opinions and forecasts contained in this document are based on Carrizo s own information and knowledge. They are provided in good faith, but, by their nature, are based on a number of assumptions and are subjective. Readers should therefore carry out appropriate reviews and due diligence to satisfy themselves as to all information contained in this document including, without limitation, Carrizo s opinions, prospect evaluations and reserves estimates. While this information was prepared in good faith, no representation or warranty, expressed or implied, is or will be made, and no responsibility or liability is or will be accepted by Carrizo or any of their respective affiliates or subsidiaries, employees, officers, directors and consultants as to, or in relation to, the accuracy or completeness of this document and any liability thereof is hereby expressly disclaimed.

1. License Information License Number P.1797 License Round 26 th Round (Award 10/1/2011) License Type Traditional Block Number 22/8a Operator/Partners % Carrizo Oil & Gas, Inc.

1797 bock 22/8a is located in the Central North Sea (Figure 1) and was awarded in the 26 th Licensing Round as a Traditional License to Carrizo Oil & Gas, Inc. as operator with 100% working interest.

2 1. License Information License Number P.1797 License Round 26 th Round (Award 10/1/2011) License Type Traditional Block Number 22/8a Operator/Partners % Carrizo Oil & Gas, Inc. (operator) 100% Carrizo Oil & Gas, Inc. has approved this relinquishment report for publication by the DECC Block 22/8a 22/8a 2. Licence Synopsis Figure 1: Location Map License P.1797 bock 22/8a is located in the Central North Sea (Figure 1) and was awarded in the 26 th Licensing Round as a Traditional License to Carrizo Oil & Gas, Inc. as operator with 100% working interest. The initial term work programme was to reprocess 50 sq km of 3D seismic data. This report is submitted at the end of the initial four year term of the license. The undeveloped 22/8-2 Chalk discovery (La Jolla) was evaluated during the initial term.

3 3. Work Programme Summary Carrizo conducted proprietary reprocessing of 110 sq km of 3-D (Pre-STM) seismic data across the block and later acquired 110 sq km of PGS MegaSurvey Plus Data in fulfillment of the license obligation. The data was first acquired by BP, PGS and Amoco in The reprocessed data was adequate to map the Fulmar prospects but did not substantially improve resolution. The reprocessed data improved resolution and frequency content in the Paleocene but AVO work was hampered by the short cable length of the original acquisition programmes. In addition, in-house post stack reprocessing of the 3-D data set undertaken to improve imaging beneath the BCU proved unsuccessful. No wells were drilled by Carrizo during the license term. 4. Database Carrizo licensed four 3D seismic data sets over Block 22/8a; 1) 110 sq km of PGS MegaSurvey data, 2) 110 sq km of PGS MegaSurvey Plus data and 3) 110 sq km of Carrizo reprocessed PGS data and 4) 20 sq km of CGGVeritas long offset data. The extent of these datasets is shown in Figure 2. CGG Veritas 3D Long Offset Data (20 km 2 ) PGS 3D MegaSurvey and MegaSurvey Plus and Carrizo reprocessed Data (110 km 2 ) La Jolla 2 Figure 2: Database and Prospect Map Fulmar prospect Santa Cruz West Aptos Ventura Pismo Santa Cruz Forties prospect Chalk prospect Malibu

4 Past well results on block 22/8 have also been incorporated into the evaluation and are summarized in the table below: Well Operator Completed TD (ft) Result Comments 22/8-1 Sun ,530 P&A, mechanical reasons Failed to reach objectives 22/8-2 Sun ,217 P&A with gas, cond. shows Tor Fm tested 4 mmcf/d 22/8-3 Ranger ,220 P&A Dry Jurassic oil and gas shows 22/8-4 Sun ,310 P&A No significant shows 5. Prospectivity Analysis Potential reservoirs exist in the Upper Jurassic Fulmar Sandstone, and the Paleocene Forties, Andrew and Maureen Sandstones. The Upper Cretaceous Tor Formation is also a potential reservoir having flowed 4 mmcf/d at the 22/8-2 well. The primary source rock is the Upper Jurassic Kimmeridge Clay Formation. Maturity modeling suggests the Kimmeridge source rock lies within the oil window along the southern and western margins of the block. To the north and east, the Kimmeridge is mature to generate gas. Seal potential occurs within the Kimmeridge Clay, Lower Cretaceous, Upper Cretaceous and Paleocene Sele Formation. Seal breach is a risk for traps charged by an overpressured Kimmeridge section generating gas. Trap types vary from structural closures to combination structural/stratigraphic traps. At the time of application, the primary exploration focus was the southern portion of the block where a Jurassic nose plunging eastward into the Fisher Bank basin contained a number of low relief structural prospects at Fulmar level. The Ventura Prospect (Forties) also overlies a portion of this feature. The reprocessing effort was intended to improve seismic imaging at both Fulmar and Forties horizons. Unfortunately, the improvements in data quality were negligible and insufficient to materially reduce trap and seal risk for the Fulmar prospects and trap risk for the Forties prospect. As a result, the license was relinquished after the initial fouryear term without drilling. Figure 3 illustrates the structural configuration of the southern portion of block 22/8a. Figure 4 is an example seismic line traversing the prospect from southwest to northeast. 6. Further Technical Work Undertaken Biostratigraphic studies of the Paleocene interval in key nearby wells was undertaken to identify depositional packages and assess the potential for stratigraphic trapping within the interval.

5 Figure 3 Base Upper Jurassic Depth Map C.I. = 50 ft North Aptos Figure 4 line location Block 22/8a Malibu Figure 4 SW BCU Fulmar Pentland NE

6 7. Resource and Risk Summary The following table summarizes the prospectivity identified on block 22/8a: Prospect Lead Discovery Name P L D Stratigraphic level Resource and Risk Summary Unrisked recoverable resources Oil (mmbo) Gas (bcf) Low Central High Low Central High Geological Chance of Success % Risked P50 (mmboe) Ventura P Forties West P Fulmar P Fulmar North P Fulmar Malibu L Fulmar Pismo L Fulmar La Jolla P Chalk-Tor Conclusions On the basis of the post-award technical assessment, the prospectivity of block 22/8a falls below Carrizo s technical risk and volumetric thresholds. As a result, Carrizo has elected to relinquish the P.1797 license at the end of the initial term on 9 th January Clearance Carrizo as operator for License P.1797 has approved this relinquishment report and confirms that DECC is free to publish and that PGS s ownership rights (on any contained data and /or interpretations) have been considered and appropriately cleared for publication purposes. MegaSurvey and MegaSurvey Plus are registered trademarks of PGS. Other trademarks belong to their respective owners.

Carrizo Oil & Gas, Inc. (op) 40% E.ON Ruhrgas UK Exploration and Production Ltd. 30% Norwegian Energy Company UK Ltd. 30%

Relinquishment Report UKCS License P.1660 25 th Round Traditional Block 22/9b February 2011 Carrizo Oil & Gas, Inc. (op) 40% E.ON Ruhrgas UK Exploration and Production Ltd. 30% Norwegian Energy Company