Exhibit 10.1

Execution Version

MASTER ASSIGNMENT, AGREEMENT AND AMENDMENT NO. 4 TO
SECOND AMENDED AND RESTATED CREDIT AGREEMENT

This Master Assignment, Agreement and Amendment No. 4 to Second Amended and
Restated Credit Agreement ("Agreement") dated as of August 13, 2014 ("Effective
Date"), is among Gastar Exploration Inc., a Delaware corporation ("Borrower"),
Wells Fargo Bank, National Association, as administrative agent for the Lenders
(as defined below) (in such capacity, the "Administrative Agent"), as collateral
agent (in such capacity, the "Collateral Agent"), as swing line lender (in such
capacity, "Swing Line Lender"), as issuing lender (in such capacity, the
"Issuing Lender"), and in its capacity as a Lender (in such capacity, the
“Assignee”), IBERIABANK, in its individual capacity as a Lender (in such
capacity, the “Assignor”), Comerica Bank, in its individual capacity as a
Lender, and ING Capital LLC, in its individual capacity as a Lender.

RECITALS

A.The Borrower is party to that certain Second Amended and Restated Credit
Agreement dated as of June 7, 2013, among the Borrower, the lenders thereto from
time to time (the "Lenders"), the Administrative Agent, the Collateral Agent,
the Swing Line Lender, and the Issuing Lender, as heretofore amended (as so
amended, the "Credit Agreement").

B.The parties hereto wish to increase the Borrowing Base under the Credit
Agreement and in connection with such increase, Assignor wishes to assign a
certain percentage of its rights and obligations under the Credit Agreement as a
Lender to Assignee pursuant to the terms hereof.

C.After the assignment and acceptance of the rights and obligations set forth
herein have been made effective, the parties hereto agree to, subject to the
terms and conditions set forth herein, (i) amend the Credit Agreement as
provided herein and (ii) increase the Borrowing Base.

THEREFORE, the Borrower, the Lenders, the Issuing Lender, the Swing Line Lender,
the Collateral Agent, and the Administrative Agent hereby agree as follows:
Section 1.Defined Terms; Interpretation. As used in this Agreement, each of the
terms defined in the opening paragraph and the Recitals above shall have the
meanings assigned to such terms therein. Each term defined in the Credit
Agreement and used herein without definition shall have the meaning assigned to
such term in the Credit Agreement, unless expressly provided to the contrary.
The words "hereby", "herein", "hereinafter", "hereof", "hereto" and "hereunder"
when used in this Agreement shall refer to this Agreement as a whole and not to
any particular Article, Section, subsection or provision of this Agreement.
Article, Section, subsection and Exhibit references herein are to such Articles,
Sections, subsections and Exhibits of this Agreement unless otherwise specified.
All titles or headings to Articles, Sections, subsections or other divisions of
this Agreement or the exhibits hereto, if any, are only for the convenience of
the parties and shall not be construed to have any effect or meaning with
respect to the other content of such Articles, Sections, subsections, other
divisions or exhibits, such other content being controlling as the agreement
among the parties hereto. Whenever the context requires, reference herein made
to the single number shall be understood to include the plural; and likewise,
the plural shall be understood to include the singular. Words denoting sex shall
be construed to include the masculine, feminine and neuter, when such
construction is appropriate; and specific enumeration shall not exclude the
general but shall be construed as cumulative. Definitions of terms defined in
the singular or plural shall be equally applicable to the plural or singular, as
the case may be, unless otherwise indicated.

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Section 1.    Assignments and Acceptances. In lieu of executing and delivering
an Assignment and Acceptance, Assignor and Assignee hereby agree to, and
Borrower hereby accepts, the following:
(a)    Assignment. For an agreed consideration, Assignor hereby irrevocably
sells and assigns to Assignee, and Assignee hereby irrevocably purchases and
assumes from Assignor, subject to and in accordance with the terms hereof and
the Credit Agreement, as of the Effective Date (i) such percentage in and to all
of Assignor’s rights and obligations in its capacity as a Lender under the
Credit Agreement and any other documents or instruments delivered pursuant
thereto to the extent related to the amount and percentage interest identified
in Schedule II hereto that would result in Assignor and Assignee having the
respective Commitments set forth in Schedule II attached hereto (including
without limitation any letters of credit and guaranties provided in connection
with the Credit Agreement), and (ii) to the extent permitted to be assigned
under applicable law, all claims, suits, causes of action and any other right of
Assignor (in its capacity as a Lender) against any Person, whether known or
unknown, arising under or in connection with the Credit Agreement, any other
documents or instruments delivered pursuant thereto or the loan transactions
governed thereby or in any way based on or related to any of the foregoing,
including, but not limited to, contract claims, tort claims, malpractice claims,
statutory claims and all other claims at law or in equity related to, and in
proportion to, the rights and obligations sold and assigned pursuant to clause
(i) above (the rights and obligations sold and assigned by Assignor to Assignee
pursuant to clauses (i) and (ii) above being referred to herein collectively as
an "Assigned Interest"). Each such sale and assignment is without recourse to
Assignor and, except as expressly provided in this Agreement, without
representation or warranty by Assignor. After giving effect to the sale and
assignment pursuant to this Section 2(a) and after giving effect to the increase
in the Borrowing Base set forth in Section 3 below, each Lender's Pro Rata Share
of the Borrowing Base will be as set forth next to its name on Schedule I
attached hereto.
(b)    Representations and Warranties of Assignor. Assignor (i) represents and
warrants that (A) it is the legal and beneficial owner of the relevant Assigned
Interest, (B) such Assigned Interest is free and clear of any lien, encumbrance
or other adverse claim, and (C) it has full power and authority, and has taken
all action necessary, to execute and deliver this Agreement and to consummate
the transactions contemplated hereby; and (ii) it assumes no responsibility with
respect to (A) any statements, warranties or representations made in or in
connection with the Credit Agreement or any other Loan Document, (B) the
execution, legality, validity, enforceability, genuineness, sufficiency or value
of the Loan Documents or any collateral thereunder, (C) the financial condition
of the Borrower, its Subsidiaries or Affiliates or any other Person obligated in
respect of any Loan Document or (D) the performance or observance by the
Borrower, its Subsidiaries or Affiliates or any other Person of any of its
obligations under any Loan Document.
(c)    Representations and Warranties of Assignee. Assignee (i) represents and
warrants that (A) it has full power and authority, and has taken all action
necessary, to execute and deliver this Agreement and to consummate the
transactions contemplated hereby and to increase its Pro Rata Share under the
Credit Agreement, (B) it meets all the requirements to be an assignee under
Section 9.07 of the Credit Agreement (subject to such consents, if any, as may
be required under Section 9.07 of the Credit Agreement), (C) from and after the
Effective Date, it shall be bound by the provisions of the Credit Agreement as a
Lender thereunder and, to the extent of the relevant Assigned Interest, shall
have the obligations of a Lender thereunder, (D) it is sophisticated with
respect to decisions to acquire assets of the type represented by the Assigned
Interest and either it, or the person exercising discretion in making its
decision to acquire the Assigned Interest, is experienced in acquiring assets of
such type, (E) it has received a copy of the Credit Agreement and has received
or has been accorded the opportunity to receive copies of the most recent
financial statements delivered pursuant to Section 5.06 thereof, and such other
documents and information as it deems appropriate to make its own credit
analysis and decision to enter into this Agreement and to purchase such Assigned
Interest, (F) it has, independently and without reliance upon the Administrative
Agent or the other Lenders and based on such documents and information as it has
deemed appropriate,

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made its own credit analysis and decision to enter into this Agreement and to
purchase such Assigned Interest, and (G) if it is not incorporated under the
laws of the United States of America or a state thereof, on or prior to the date
hereof, it has delivered to Administrative Agent any documentation required to
be delivered by it pursuant to the terms of the Credit Agreement, duly completed
and executed by it; and (ii) agrees that (A) it will, independently and without
reliance on the Administrative Agent any Assignor or any other Lenders, and
based on such documents and information as it shall deem appropriate at the
time, continue to make its own credit decisions in taking or not taking action
under the Loan Documents, and (B) it will perform in accordance with their terms
all of the obligations which by the terms of the Loan Documents are required to
be performed by it as a Lender.
(d)    Payments. From and after the Effective Date, Administrative Agent shall
make all payments in respect of each Assigned Interest (including payments of
principal, interest, fees and other amounts) to Assignee whether such amounts
have accrued prior to, on or after the Effective Date. Assignor and Assignee
shall make all appropriate adjustments in payments by Administrative Agent for
periods prior to the Effective Date or with respect to the making of this
assignment directly between themselves.
(e)    Consent; Waiver of Administrative Fees. Administrative Agent and Borrower
hereby consent to Assignor’s assignment of the Assigned Interests to Assignee
and a one-time waiver of the $3,500 administrative fees that would otherwise be
payable by Assignee pursuant to Section 9.07(b)(iv) of the Credit Agreement as a
result of the assignment provided for herein, and waive any other conditions to
the effectiveness of such assignment that are not expressly set forth in this
Agreement, including, but not limited, the condition set forth in Section
9.07(b)(i)(B) of the Credit Agreement, and agree that the terms of this
Agreement shall constitute an Assignment and Acceptance.
Section 2.    Agreement - Increase in Borrowing Base. Subject to the terms of
this Agreement, as of the Effective Date, the Borrowing Base shall be increased
by $25,000,000, resulting in a new Borrowing Base equal to $145,000,000. Such
new Borrowing Base shall remain in effect at that level until the effective date
of the next Borrowing Base redetermination made in accordance with the Credit
Agreement, as amended hereby. The parties hereto acknowledge and agree that the
Borrowing Base redetermination set forth in this Section 3 shall be deemed to be
the scheduled, fall redetermination provided for in Section 2.02(b)(ii) of the
Credit Agreement. Each Lender's Pro Rata Share of the resulting Borrowing Base,
after giving effect to the assignment made pursuant to Section 2 above and the
increase in the Borrowing Base set forth in this Section 3, is set forth in
Schedule I attached hereto.
Section 3.    Amendments to Credit Agreement. Schedule II (Notice Information
and Commitments) to the Credit Agreement is hereby replaced in its entirety with
Schedule II (Notice Information and Commitments) attached hereto.
Section 4.    Representations and Warranties. Each Loan Party represents and
warrants that: (a) after giving effect to this Agreement, the representations
and warranties contained in the Credit Agreement and the representations and
warranties contained in the other Loan Documents are true and correct in all
material respects (except that such materiality qualifier shall not be
applicable to any representations and warranties that already are qualified or
modified by materiality in the text thereof) on and as of the date hereof;
(b) after giving effect to this Agreement, no Default has occurred and is
continuing; (c) the execution, delivery and performance of this Agreement are
within the corporate, partnership, or limited liability company power and
authority of such Loan Party, as applicable, and have been duly authorized by
appropriate corporate, partnership, or limited liability company action and
proceedings, as applicable; (d) this Agreement constitutes the legal, valid, and
binding obligation of such Loan Party enforceable in accordance with its terms,
except as limited by applicable bankruptcy, insolvency, reorganization,
moratorium, or similar laws affecting the rights of creditors generally and
general principles of equity; (e) there are no governmental or

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other third party consents, licenses and approvals required in connection with
the execution, delivery, performance, validity and enforceability of this
Agreement; (f) the Liens under the Security Instruments are valid and subsisting
and secure the Secured Obligations; and (g)  after giving effect to this
Agreement, assuming that the Borrower makes Borrowings, or otherwise has
Borrowings outstanding, of an amount that causes Availability to be equal to
zero Dollars, all such Borrowings were permitted to be incurred and secured
under the Second Lien Loan Documents.
Section 5.    Conditions to Effectiveness. This Agreement and the amendments
provided herein shall become effective and enforceable against the parties
hereto upon the occurrence of the following conditions precedent:
(a)    Administrative Agent shall have received multiple original counterparts,
as requested by Administrative Agent, of the following, duly and validly
executed and delivered by duly authorized officers of the parties thereto:
i.this Agreement and all attached Schedules;
ii.a replacement Revolving Note payable to Assignor or its registered assigns;
iii.a replacement Revolving Note payable to Assignee or its registered assigns;
(b)    the representations and warranties in this Agreement made by Borrower
shall be true and correct in all material respects; and
(c)    Borrower shall have paid the fee required under Section 7(f) below.
Section 6.    Effect on Loan Documents; Acknowledgments.
(a)    The Borrower acknowledges that on the date hereof all Obligations are
payable without defense, offset, counterclaim or recoupment.
(b)    The Administrative Agent, the Collateral Agent, the Issuing Lender, the
Swing Line Lender, and the Lenders hereby expressly reserve all of their rights,
remedies, and claims under the Loan Documents. Nothing in this Agreement shall
constitute a waiver or relinquishment of (i) any Default or Event of Default
under any of the Loan Documents, (ii) any of the agreements, terms or conditions
contained in any of the Loan Documents, (iii) any rights or remedies of the
Administrative Agent, the Collateral Agent, the Issuing Lender, the Swing Line
Lender, or any Lender with respect to the Loan Documents, or (iv) the rights of
the Administrative Agent, the Collateral Agent, the Issuing Lender, the Swing
Line Lender, or any Lender to collect the full amounts owing to them under the
Loan Documents.
(c)    Each of the Borrower, the Administrative Agent, the Collateral Agent, the
Issuing Lender, the Swing Line Lender, and the Lenders does hereby adopt,
ratify, and confirm the Credit Agreement, as amended hereby, and acknowledges
and agrees that the Credit Agreement, as amended hereby, and all other Loan
Documents are and remain in full force and effect, and the Borrower acknowledges
and agrees that its liabilities under the Credit Agreement and the other Loan
Documents are not impaired in any respect by this Agreement.
(d)    From and after the Effective Date, all references to the Credit Agreement
and the Loan Documents shall mean such Credit Agreement and such Loan Documents
as amended prior hereto as described in the recitals, and by this Agreement.

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(e)    This Agreement is a Loan Document for the purposes of the provisions of
the other Loan Documents. Without limiting the foregoing, any breach of
representations, warranties, and covenants under this Agreement shall be a
Default or Event of Default, as applicable, under the Credit Agreement.
(f)    The Borrower hereby agrees to pay a Borrowing Base increase fee for the
account of each Lender, after giving effect to the sales and assignments made
pursuant to Section 2 above, equal to 0.30% of the amount by which such Lender’s
Pro Rata Share of the new Borrowing Base, as set forth on Schedule I and
increased pursuant to Section 3 above, exceeds such Lender’s Pro Rata Share of
the existing Borrowing Base, as set forth on Schedule I. Such increase fee is
(i) due and payable on the Effective Date, (ii) deemed fully earned upon
becoming due and payable, (iii) not refundable under any circumstance upon
payment thereof, and (iv) in addition to, and not in lieu of, any other fees as
the Borrower may have agreed to pay under the other Loan Documents.
Section 7.    Counterparts. This Agreement may be signed in any number of
counterparts, each of which shall be an original and all of which, taken
together, constitute a single instrument. This Agreement may be executed by
facsimile or email (i.e., PDF) signature and all such signatures shall be
effective as originals.
Section 8.    Successors and Assigns. This Agreement shall be binding upon and
inure to the benefit of the Borrower, the Lenders, the Issuing Lender, the Swing
Line Lender, the Collateral Agent, and the Administrative Agent and their
respective successors and assigns permitted pursuant to the Credit Agreement.
Section 9.    Invalidity. In the event that any one or more of the provisions
contained in this Agreement shall for any reason be held invalid, illegal or
unenforceable in any respect, such invalidity, illegality or unenforceability
shall not affect any other provision of this Agreement.
Section 10.    Governing Law. This Agreement shall be deemed a contract under,
and shall be governed by, and construed and enforced in accordance with, the
laws of the State of New York applicable to contracts made and to be performed
entirely within such state, without regard to conflicts of laws principles
(other than Section 5-1401 and Section 5-1402 of the General Obligations Law of
the State of New York).
Section 11.    Waiver of Jury. THE BORROWER, THE LENDERS, THE ISSUING LENDER,
AND THE AGENTS HEREBY ACKNOWLEDGE THAT THEY HAVE BEEN REPRESENTED BY AND HAVE
CONSULTED WITH COUNSEL OF THEIR CHOICE, AND HEREBY KNOWINGLY, VOLUNTARILY,
INTENTIONALLY, AND IRREVOCABLY WAIVE ANY AND ALL RIGHT TO TRIAL BY JURY IN
RESPECT OF ANY LEGAL PROCEEDING ARISING OUT OF OR RELATING TO THIS AGREEMENT,
ANY OTHER LOAN DOCUMENT, OR ANY OF THE TRANSACTIONS CONTEMPLATED HEREBY OR
THEREBY.
Section 12.    Entire Agreement. THIS AGREEMENT, THE CREDIT AGREEMENT AS AMENDED
BY THIS AGREEMENT, THE NOTES, AND THE OTHER LOAN DOCUMENTS CONSTITUTE THE ENTIRE
UNDERSTANDING AMONG THE PARTIES HERETO WITH RESPECT TO THE SUBJECT MATTER HEREOF
AND SUPERSEDE ANY PRIOR AGREEMENTS, WRITTEN OR ORAL, WITH RESPECT THERETO.
[The remainder of this page has been left blank intentionally.]

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EXECUTED effective as of the date first above written.

BORROWER:

GASTAR EXPLORATION INC.

By: /s/ Michael A. Gerlich    
Michael A. Gerlich
Senior Vice President, Chief Financial Officer and
Corporate Secretary

Signature Page to
Master Assignment, Agreement and Amendment No. 4 to
Second Amended and Restated Credit Agreement
(Gastar Exploration Inc.)

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ADMINISTRATIVE AGENT/COLLATERAL AGENT/ISSUING LENDER/SWING LINE
LENDER/LENDER/ASSIGNEE:

WELLS FARGO BANK, NATIONAL ASSOCIATION

By: /s/ Stephanie Harrell    
Stephanie Harrell
Assistant Vice President

Signature Page to
Master Assignment, Agreement and Amendment No. 4 to
Second Amended and Restated Credit Agreement
(Gastar Exploration Inc.)

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LENDER:

COMERICA BANK

By:    /s/ William Robinson    
Name:    William Robinson
Title:    Vice President

Signature Page to
Master Assignment, Agreement and Amendment No. 4 to
Second Amended and Restated Credit Agreement
(Gastar Exploration Inc.)

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LENDER/ASSIGNOR:

IBERIABANK

By:    /s/ Moni Collins    
Name:    Moni Collins
Title:    Vice President

LENDER:

ING CAPITAL LLC

By:    /s/ Josh Strong    
Name:    Josh Strong
Title:    Director

ING CAPITAL LLC

By:    /s/ Charles Hall    
Name:    Charles Hall
Title:    Managing Director

SCHEDULE I
BORROWING BASE
Lenders:
Pro Rata Share of existing Borrowing Base
Pro Rata Share of Borrowing Base*
Wells Fargo Bank, National Association
$36,000,000
$44,750,000
Comerica Bank
$30,000,000
$36,250,000
IBERIABANK
$30,000,000
$35,000,000
ING Capital LLC
$24,000,000
$29,000,000
Total:
$120,000,000
$145,000,000

*Borrowing Base in effect as of August 13, 2014. Borrowing Base is subject to
redetermination pursuant to the terms of this Agreement.

SCHEDULE II
NOTICE INFORMATION AND COMMITMENTS
Each of the commitments to lend set forth herein is governed by the terms of the
Credit Agreement which provides for, among other things, borrowing base
limitations which may restrict the Borrower’s ability to request (and the
Lenders’ obligation to provide) Credit Extensions to a maximum amount which is
less than the commitments set forth in this Schedule II.
Administrative Agent/Collateral Agent/Issuing Lender/Swing Line Lender:
Wells Fargo Bank, National Association
1525 West WT Harris Boulevard – 1B1
Charlotte, North Carolina 28262
Attention: Agency Services Manager
Facsimile: (704) 715-0017
with a copy to:
Wells Fargo Bank, National Association
1000 Louisiana, 9th Floor
MAC T0002-090
Houston, Texas 77002
Attention: Charles Randall
Facsimile: (713) 319-1925
Borrower:
Gastar Exploration Inc.
1331 Lamar Street, Suite 1080
Houston, Texas 77010
Attention: Michael Gerlich
Facsimile: (713) 739-0458
Lenders:
Commitments
Percentage of Total
Wells Fargo Bank, National Association

$154,310,345

30.862069
%
Comerica Bank

$125,000,000

25.000000
%
IBERIABANK

$120,689,655

24.137931
%
ING Capital LLC

$100,000,000

20.000000
%
Total:

$500,000,000

100.000000
%

Signature Page to
Master Assignment, Agreement and Amendment No. 4 to
Second Amended and Restated Credit Agreement
(Gastar Exploration Inc.)