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DUG Permian PresentationThe Southern Midland Basin: A Hydrocarbon Menu

September 2020

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DisclaimerCAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTSThis Presentation and the oral statements made in connection with it, may include “forward-looking statements.” All statements, other than

statements of historical facts, concerning, among other things, planned capital expenditures, increases in oil and gas production, the number of

anticipated wells to be drilled or completed after the date of this Presentation, future cash flows and borrowings, pursuit of potential acquisition

opportunities and our financial position, business strategy and other plans and objectives of management are forward-looking statements. These

forward-looking statements may be identified by their use of terms and phrases such as “may,” “expect,” “estimate,” “project,” “plan,” “believe,”

“intend,” “achievable,” “anticipate,” “will,” “continue,” “potential,” “should,” “could,” and similar terms and phrases. Forward-looking statements are

subject to risks and uncertainties, and are not guarantees of future performance. Actual results or developments may differ materially from the

projections in the forward-looking statements. These forward-looking statements are based on management’s current expectations and assumptions

about future events and are based on currently available information as to the outcome and timing of future events. We do not undertake any

obligation to release the result of any revisions to these forward-looking statements to reflect events or circumstances after the date of this

Presentation to reflect the occurrence of unanticipated events. All forward-looking statements attributable to us or persons acting on our behalf are

expressly qualified in their entirety by this cautionary statement. This cautionary statement should also be considered in connection with any

subsequent written or oral forward-looking statements that we or persons acting on our behalf may issue. Except as required by applicable law, we do

not assume a duty to update these forward-looking statements, whether as a result of new information, subsequent events or circumstances, changes

in expectations or otherwise.

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2020+ Focusü High Rate of Return

ü Positive Cashflow

ü Grow Production

ü Pay down Debt

Mariner

Sequitur

• 200 Bcfe, 29% Proved Developed (“PD”) Reserves

• Highly Levered• Primary assets in GoM Shelf and

Deepwater• Operated within cashflow• Acquired by PE firms

ACON/Riverstone

2001 - 2004• PE firms exited in 144A Offering• NYSE listed through Reverse

Morris Trust with Forest Oil• Expanded position in core of

Permian Basin to 150,000 net acres through acquisition and leasing

2005 - 2009• >$4B merger with Apache• 1.2 Tcfe, 70% PD and 50% oil• Primary assets in Permian Basin,

GoM Shelf and Deepwater

2010

• Formed Sequitur • Purchased East Texas asset.

Initiated multi-rig development program

• Continued looking for stacked pay growth opportunities

2011 - 2015• Acquired Southern Midland

Basin (“SMB”) assets from EOG• Increased SMB footprint and

production through acquisition and drilling

• Acquired Callon’s SMB position

2016 - 2019

Sequitur Formed by Mariner Executive Management Team

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Large Contiguous, Operated Position

§ Current Production ~ 30,000 Boepd 30% oil, 65% liquids

§ ~90,000 net acres with ~60,000 net acres on University Lands

§ 100% operated with average 89% WI and > 8,500 average lateral length

§ YE19 PDP Reserves: 105 MMBoe

§ YE 19 Proved Reserves: 212 MMBoe

Large Inventory of De-Risked Locations

§ ~800 locations at 880’ spacing, excluding upside locations

§ IRR’s of 30-50% in current commodity price environment

§ Consistent and proven results with ~380 horizontal producing wells

§ 3D seismic coverage on > 90% of acreage

Infrastructure in Place to

Accommodate Growth

§ ~65 miles of gas gathering lines connected to 3 separate gas processing companies

§ 32 frac ponds totaling ~12MM bbls capacity, and ~150 source water wells

§ ~90 miles of water lines connected to 10 saltwater disposal wells

§ 1 produced water pond with recycling facility in Barnhart

§ Texon wells deliver oil via pipeline

Sequitur Overview

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Primary Targets Upside Targets

SER AcreageBarnhart Area

Texon Area

Shallower, Gassier,

Lower Opex& Capex

Deeper, Oilier, Higher Opex & Capex

LS

WC A

WC B

WC C

WC C2

WC D

3,50

0’ o

f Sta

cked

Pay

Sequitur’s Acreage Position is in the Thickest Part of WC

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SMB Operators’ Acreage Positions

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$3.08 $3.15 $3.45

$4.58 $5.26

$5.68 $5.85 $5.92 $6.09

$6.93

Average: $5.00

Peer 4 SER Peer 3 Peer 1 Peer 9 Peer 8 Peer 6 Peer 5 Peer 7 Peer 2

$1.05

$1.57 $1.64 $1.78 $1.90 $1.99

$2.46 $2.57

$3.87 $4.19

Average: $2.30

818

81 34

346

76

331

41 141

13 88

Peer 1 Peer 4 SER Peer 2 Peer 9 Peer 5 Peer 7 Peer 3 Peer 6 Peer 8

2019 Avg. Production (MBoe/d)

Comparison to West Texas Peers

(1) Cash G&A excludes stock-based comp, transaction costs and other non-cash expenses; SER excludes monitoring fees, acquisition and divestiture expenses related to the Cavalier acquisition and East Texas saleNote: Peers include CDEV, CPE, CXO, EOG, ESTE, LPI, PE, PXD, QEPSource: Public company filings

2019 Cash G&A / Boe (1)

2019 West Texas LOE / Boe

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CONFIDENTIAL

Key Points

§ Continue to see improvements in completion efficiencies

- Largely driven by self-sourced sand, fuel and chemicals

- Negotiated favorable frac contract

§ Large inventory of long lateral locations also expected to drive improved efficiencies

§ Continue to evaluate new completion techniques to cost effectively enhance well performance

Decreasing D&C Cost/ft even with high Frac Intensity

$776 $766

$711

$637

$516

2,263

2,525

2,524 2,520 2,500

-

200

400

600

800

1,000

1,200

1,400

1,600

1,800

2,000

2,200

2,400

2,600

$-

$100

$200

$300

$400

$500

$600

$700

$800

$900

$1,000

2017 2018 2019 Est. 2020YTD

Bank 2Q20PUDs

Sand

(lb/

ft)

Cos

t/L

ater

al ft

Cost/Lateral Ft Sand (lb/ft)

2020 Est. 2H2020201920182017

West Texas Capex Progression

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Texon - 863 WellsBarnhart - 1,442 Wells

Data from IHS

Texon & Barnhart Type Curve Analog Map

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Data from IHS

Texon Well Performance by Frac Generation

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231,691

286,109

0

50,000

100,000

150,000

200,000

250,000

300,000

350,000

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38

Cum

ulat

ive

BO

E (N

orm

aliz

ed to

7,5

00')

Month

GEN_I (Less SER) GEN_II (Less SER) GEN_III (Less SER) GEN_IV (Less SER) Gen_IV (SER Only)

1,442 wells by 14 operators

Data from IHS

Barnhart Well Performance by Frac Generation

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2020 New Wells versus Type Curve