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Exhibit 10.1

PURCHASE AND SALE AGREEMENT

This Purchase and Sale Agreement ("Agreement") is made this 31st day of March
2010, between Macquarie Barnett, LLC, a Delaware limited liability company,
whose address is One Allen Center, 500 Dallas Street, Suite 3520, Houston, Texas
77002 ("Seller"), and Kodiak Oil & Gas (USA) Inc., a Colorado corporation, whose
address is 1625 Broadway, Ste. 250 Denver, CO 80202 ("Purchaser").

RECITALS

WHEREAS, Seller desires to sell to Purchaser, and Purchaser desires to purchase
from Seller on the terms and conditions set forth in this Agreement certain oil
and gas interests, properties and related rights.

NOW, THEREFORE, for good and valuable consideration and the covenants and
agreements contained herein, Seller and Purchaser agree as follows:

I.

PURCHASE AND SALE

1.1Effective Date and Assets:    Subject to the terms and conditions of this
Agreement, Seller shall sell and Purchaser shall purchase and pay for at Closing
(as defined herein), effective as of 7:00 a.m. on March 31, 2010 ("Effective
Date"), all of Seller's right, title and interest in and to the following
(collectively, the "Assets"):

(a)The oil and gas leasehold interests set forth in Exhibit "A" attached hereto
and made a part hereof ("Leasehold Property");

(b)All wells and wellbores located on the Leases and described on Exhibit A (the
"Wells"), together with corresponding interests in and to all personal property,
equipment, fixtures and improvements located in or on, or incident or
attributable to, the Leases, or used or obtained in connection with the
production, treatment, sale or disposal of hydrocarbons or water produced
therefrom (collectively, the "Equipment") and,

(c)Any easements, rights of way, permits, licenses, surface leases, use
agreements, and servitudes to the extent assignable, and to the extent now being
used in connection with the Leasehold Property, together with all of Seller's
rights and interests in and to all pooling and unitization agreements, operating
agreements, contracts and other agreements and instruments to the extent that
they directly relate to the Leasehold Property; except any insurance contracts
or bonds held by Seller or its parent, subsidiary or affiliated corporations for
Seller's benefit; and any employment, consulting, office lease, accounting or
other service contracts or agreements; and,

(d)Subject to any restrictions on Seller's disclosure of same, the following
records relating to the Leasehold Property: lease files, unit files, lease
contract files, well files and geological data (but excluding all other records,
including, but not limited to, corporate records, legal files, computer
programs, general tax records, samples, test data and any seismic, geophysical,
interpretive, proprietary or confidential data, information or documents)
(collectively, the "Data").

It is specifically agreed that Seller is not selling and Purchaser is not
purchasing the following assets ("Excluded Assets"):

(i)any and all interests in the Assets Seller is legally or contractually
restricted from selling;

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(ii)all materials and equipment leased or temporarily located on the Leasehold
Property, and any materials, equipment, pipelines, facilities or interests in
the land owned by a purchaser and/or transporter of oil and/or gas therefrom, a
lessor, or a third Person;

(iii)all amounts due or payable to Seller as adjustments or refunds under any
contracts affecting the Assets for all periods of time prior to the Effective
Date, specifically including, without limitation, amounts recoverable from
audits under operating agreements;

(iv)all rights, titles, claims and interests of Seller or its Affiliates to or
under any policy or agreement of insurance or indemnity, any bond, or to any
insurance proceeds or awards; and any employment, consulting, office lease or
accounting service contracts;

(v)all claims of Seller arising from acts, omissions or events, or damages to or
destruction of property, occurring prior to the Effective Date;

(vi)all proceeds, benefits, refunds, settlement, income or revenue accruing and
attributable to the Assets prior to the Effective Date, and any claims of Seller
for refunds of or losses carried forwards with respect to taxes attributable to
the Assets for any period prior to the Effective Date; and

(vi)all geophysical, geological and seismic data, surveys, analysis and similar
data or information, which is not specifically licensed to Purchaser under a
separate geophysical data licensing agreement.

1.2Closing:    Closing, as used herein, shall mean the date on which the
Purchase Price (as defined below) is to be paid to Seller and the conveyancing
instruments (as described herein) are to be delivered to Purchaser. Closing
shall occur at or before 9:00 a.m. on or before March 31, 2010 at Seller's
office or at such other place, date and time as may be mutually agreed upon by
Seller and Purchaser.

1.3Assumption of Obligations:    From and after the Effective Date, Purchaser
shall personally assume, pay for, discharge, be responsible for, perform and
comply with all duties, liabilities and obligations of Seller, express or
implied, relating to the Assets, including, but not limited to, those arising
from or by virtue of any lease, agreement, contract and instrument, whether
recorded or unrecorded, including, but not limited to the agreements and
contracts described herein or an exhibit hereto, and those arising from or by
virtue of any permit, statute, rule, regulation or order of any governmental
authority, together with all Assumed Liabilities (as hereinafter defined),
REGARDLESS OF WHETHER ATTRIBUTABLE (IN WHOLE OR IN PART) TO THE SOLE, JOINT OR
CONCURRENT NEGLIGENCE, STRICT LIABILITY, BREACH OF CONTRACT, ENVIRONMENTAL
LIABILITY, REGULATORY LIABILITY OR OTHER FAULT OR RESPONSIBILITY OF SELLER OR
ANY OTHER PERSON OR PARTY. For purposes hereof, the following terms shall have
the following respective definitions:

"Assumed Liabilities" means (1) all General Liabilities, (2) all Environmental
Liabilities, (3) all Plugging and Abandonment Obligations and (4) all other
liabilities and obligations assumed by Purchaser under the terms of this
Agreement.

"General Liabilities" means all obligations, duties, losses, liabilities,
claims, fines, expenses, damages, costs (including attorneys fees and expenses)
or penalties created by, related to, or arising out of ownership or operation of
the Assets, any contractual relationship, or any applicable law, order, rule,
regulation, judgment or decree of any federal, state, tribal, county or
municipal governing authority having jurisdiction over the Assets or the
Parties, whether Accruing before or after the Effective Date and whether
attributable, in whole or in part, to actions, events or conditions existing or
occurring before or after the Effective Date; excluding only those obligations,

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duties or liabilities for the payment of royalties, and taxes which Accrued
prior to the Effective Date.

"Environmental Laws" means any applicable laws, orders, rules, regulations,
judgments or decrees of any federal, state, tribal, county or municipal
governing authority having jurisdiction over any Asset or Party which relate to
pollution, the protection or cleanup of the environment, or the release or
disposal of deleterious substances into the environment, including but not
limited to ambient air, surface water, groundwater, land surface or subsurface
strata; including all such laws, orders, rules, regulations, judgments or
decrees as they may be amended, varied or modified in the future.

"Environmental Liabilities" means all obligations, duties, losses, liabilities,
claims, fines, expenses, damages, costs (including attorney's fees and expenses)
or penalties created by, related to, or arising out of any Environmental Law,
whether Accruing before or after the Effective Date, and whether attributable,
in whole or in part, to actions, events or conditions existing or occurring
before or after the Effective Date.

"Plugging and Abandonment Obligations" means all usual and normal prudent
operations for the plugging, abandonment, surface, waterbottom, or seabed
restoration, site clearance, and disposal of related waste materials, including
NORM and asbestos, of all oil, gas, injection, water or other wells, sumps,
pits, ponds, tanks, impoundments, foundations, pipelines, structures and
equipment of any kind or description on the Assets, in compliance with all
applicable contractual obligations and applicable rules and regulations of
governmental bodies having jurisdiction over the Assets. Plugging and
Abandonment Obligations do not include cleanup of polluted lands, air or water
other than routine cleanup normally associated with plugging and abandonment
(such cleanup obligations which are other than routine being included within the
definition of Environmental Liabilities).

"Accruing" or "Accrued" means, with respect to any obligation, duty, loss,
liability, claim, fine, expense, damage, cost or penalty, the occurring or
happening of any event which causes such obligation, duty, loss, liability,
claim, fine, expense, damage, cost or penalty to become demandable, requirable,
assertible, enforceable, due and owing, or being incurred or occurring, as the
case may be.

II.

CONSIDERATION

2.1Purchase Price:    Subject to the terms and conditions of this Agreement,
Purchaser shall purchase the Assets at Closing for Seven Million Five Hundred
Thousand dollars ($7,500,000) ("Purchase Price"), in cash. At Closing, Purchaser
shall pay to Seller the Purchase Price by cashier's check or wire transfer of
cash in United States Currency, in a manner specified by Seller in writing.

III.

TITLE EXAMINATION

3.1Access to Title Information:    Seller has made the Data available to
Purchaser at Seller's office located at Macquarie Cook Energy, 999 18th Street,
Suite 2950, Denver, CO, 80202 and Macquarie One Allen Center, 500 Dallas Street,
Suite 3250, Houston, TX, 77002, or such other place as deemed appropriate by
Seller, for examination by Purchaser. Purchaser has completed such due diligence
review of the Data as Purchaser deems necessary and appropriate prior to the
execution of this Agreement and has satisfied itself with the current state of
Seller's title to the Assets. Seller shall not be obligated to perform any
additional title work, and any additional abstracts and title opinions will not
be made current by Seller. NO WARRANTY OR REPRESENTATION OF

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ANY KIND IS MADE BY SELLER, AS TO THE INFORMATION SO SUPPLIED, AND PURCHASER
AGREES THAT ANY CONCLUSIONS DRAWN THEREFROM SHALL BE THE RESULT OF ITS OWN
INDEPENDENT REVIEW AND JUDGMENT. SUBJECT TO THE OTHER PROVISIONS OF THIS
AGREEMENT, PURCHASER ASSUMES THE RISK OF ANY TITLE DEFECTS AND/OR CONFLICTING
ADVERSE RIGHT(S), TITLE(S) AND/OR INTEREST(S) WHICH A RECORD TITLE CHECK AND/OR
PHYSICAL INSPECTION REVEALS OR WOULD HAVE REVEALED.

IV.

ENVIRONMENTAL CONDITION

4.1Environmental Assessment:    Prior to executing this Agreement, Purchaser and
its agents have been given the right to enter upon the Assets and all buildings
and improvements thereon to inspect the same and Purchaser has conducted such
soil and water tests and borings, examinations, investigations and studies and
has prepared and reviewed such engineering and other reports and evaluations
relating to the Assets, their condition, and the presence of waste or
contaminants as Purchaser has deemed necessary or appropriate.

4.2"As Is, Where Is" Purchase:    Purchaser shall acquire the Assets in their
"AS IS, WHERE IS, WITH ALL FAULTS" condition and shall assume the risks that the
Assets may contain waste materials, contaminants or hazardous substances, that
adverse physical conditions, including, but not limited to, the presence of
waste materials, contaminants or hazardous substances or the presence of unknown
abandoned oil and gas wells, water wells, pits, sumps and pipelines may not have
been revealed by Purchaser's investigation, including, but not limited to, any
and all Environmental Liabilities and other Assumed Liabilities. On and after
the Effective Date, all responsibility and liability related to all such adverse
environmental conditions, whether known or unknown, shall be transferred to and
borne solely by Purchaser.

V.

[RESERVED]

VI.

REPRESENTATIONS

6.1Existence:    Purchaser and Seller represent that they are duly organized,
validly existing, and in good standing and duly qualified at Closing to carry on
business in the state(s) where the Assets are located.

6.2Authorization:    Purchaser and Seller have the corporate power to enter into
and perform this Agreement and the transactions contemplated hereby. The
execution, delivery and performance of this Agreement and the transactions
contemplated hereby have been duly and validly authorized by all requisite
corporate action on the part of Purchaser and Seller. This Agreement has been
duly executed and delivered on behalf of Purchaser and Seller respectively, and
at Closing all documents and instruments required hereunder to be executed and
delivered by Purchaser and Seller shall have been fully executed and delivered.

6.3Brokers:    Purchaser and Seller have not incurred any obligation or
liability, contingent or otherwise, for brokers' or finders' fees with respect
to the matters provided for in this Agreement which will be the responsibility
of the other party; and any such obligation or liability that may exist shall be
the sole obligation of the creating party.

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6.4Further Distribution:    Purchaser is acquiring the Assets for its own
account and not with the intent of making a distribution thereof within the
meaning of the Security Act of 1933 and the rules and regulations pertaining to
it, or a distribution thereof in violation of any applicable securities laws.

6.5Relation to Assumed Liabilities:    No representation or warranty contained
herein shall be deemed a representation or warranty by Seller which abrogates
the obligations of Purchaser to investigate the Assets, and make an independent
decision to purchase the Assets; and Purchaser's obligations herein with respect
to the investigation of, and independent decision to purchase the Assets, are
not diminished by any representations or warranties herein.

6.6Federal Leases:    Purchaser represents and warrants that it is qualified to
own federal oil and gas leases or will be so qualified at Closing.

VII.

CONDITIONS OF CLOSING

Purchaser's and Seller's obligations to consummate the transactions provided for
herein are subject to the satisfaction or waiver by the other party of the
following conditions:

7.1Representations:    The representations of Purchaser and Seller contained in
Article VI hereof shall be true and correct in all material respects on the date
of Closing as though made on and as of that date.

7.2Performance:    Both Purchaser and Seller shall have performed in all
material respects the obligations, covenants and agreements hereunder to be
performed by them at or prior to Closing.

7.3Pending Matters:    No suit, action or other proceeding by a third party or a
governmental authority shall be pending or threatened which seeks substantial
damages from Purchaser or Seller in connection with the Assets, or seeks to
restrain, enjoin or otherwise prohibit the consummation of the transactions
contemplated by this Agreement.

7.4Governmental Bonds:    Purchaser shall have delivered to Seller
either:    (i) copies of any bonds covering the Assets required under any laws,
rules or regulations of any federal, state or local governmental agency having
jurisdiction over the Assets issued by corporate sureties satisfactory to
Seller; or (ii) a commitment by a surety company, satisfactory to Seller, to
issue such bonds upon Closing, and (iii) copies of all other necessary or
appropriate consents, permits, insurance, approvals, authorizations and similar
items required of Purchaser to purchase, receive, own, and operate the Assets as
of the Closing and to otherwise transact business in the applicable
jurisdiction(s).

7.5Consents and Waivers:    All necessary consents, permissions and approvals by
third parties in connection with the sale and transfer of the Assets shall have
been received prior to Closing, except those governmental consents customarily
generated and received in the ordinary course of business at a post-Closing
date.

VIII.

CLOSING

8.1Closing Items:    At Closing, as defined in Section 1.2 hereof, the following
shall occur:

(a)Seller shall execute, acknowledge and deliver to Purchaser an Assignment,
Conveyance and Bill of Sale for the Assets in the form attached hereto as
Exhibit B (the "Assignment"), which Assignment shall be without warranty of
title other than a special limited warranty of title to the Assets against all
claims, liens, liabilities and encumbrances arising by, through or under Seller,
but not otherwise. As appropriate, Seller shall also execute, acknowledge and
deliver at

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Closing separate assignments of the Leases on officially approved federal and
state forms in sufficient counterparts to satisfy applicable statutory and
regulatory requirements.

(b)Seller shall deliver a certificate evidencing that it is not a "foreign
person" under the Intemal Revenue Code and Seller shall deliver the original
Records and Agreements to Purchaser.

(c)Purchaser shall deliver to Seller either by cashier's check or wire transfer
of cash as specified by Seller the Purchase Price as adjusted hereunder.

(d)Purchaser shall provide Seller with executed non-foreign affidavits, and such
other instruments and documents as may be reasonably requested by Seller.

Immediately after Closing, Purchaser shall notify all pertinent operators,
non-operators, oil or gas purchasers, governmental agencies and royalty owners
that it has purchased the Assets.

IX.

CONTINUING OBLIGATIONS

9.1Indemnities:

(a)Purchaser agrees to indemnify, defend and hold harmless Seller, its officers,
directors, employees, agents, representatives and affiliated or parent companies
(which additional parties are hereinafter collectively referred to as "Seller
Agents") from and against any and all losses, liabilities, causes of action,
damages, liens, penalties, fines, settlements, judgments, expenses, attorney's
fees, court costs and claims (hereinafter referred to collectively as "claims")
arising (i) from the breach of this Agreement by Purchaser, (ii) from the
Assumed Liabilities, or (iii) on or after the Effective Date, in any way
connected with, attributable to, or resulting from Purchaser's ownership or
operation of, or activities on the Assets, including, but not limited to, claims
for damage to property or injury or death to persons, claims for breach of
duties and obligations arising under or by virtue of any lease, contract,
agreement, permit, applicable statute or rule. Purchaser's obligations to
indemnify, defend and hold harmless, as set forth above, shall also specifically
extend to all such claims REGARDLESS OF WHETHER ATTRIBUTABLE, IN WHOLE OR IN
PART TO, CLAIMS WHICH ARE KNOWN OR UNKNOWN, CLAIMS ARISING FROM THE SOLE, JOINT,
CONCURRENT NEGLIGENCE, STRICT LIABILITY, BREACH OF CONTRACT, ENVIRONMENTAL
LIABILITY, PRODUCTS LIABILITY, OR OTHER FAULT OR RESPONSIBILITY OF SELLER, ITS
SELLER AGENTS OR ANY OTHER PARTY OR PERSON, AND REGARDLESS WHETHER OR NOT SUCH
CLAIMS AROSE PRIOR TO THE EFFECTIVE DATE OR RELATE TO CONDITIONS THAT EXISTED
PRIOR TO THE EFFECTIVE DATE. In addition, and without limiting the generality of
the foregoing, Purchaser shall be solely liable and responsible for the proper
plugging and abandoning of all wells now located on or hereafter drilled on the
Assets, and any surface restoration or environmental clean-up associated
therewith, and shall indemnify, defend and hold harmless Seller and its agents
from and against all claims relating to same.

(b)Except as otherwise set forth herein and except for the Assumed Liabilities
of Purchaser, Seller agrees to indemnify, defend and hold harmless, Purchaser
and its agents from and against any and all claims arising from the breach of
this Agreement by Seller.

(c)Any claim for indemnity under any provision of this Agreement shall be made
by written notice from the party seeking indemnification (the "Indemnified
Party") to the party required to provide same (the "Indemnifying Party"),
together with a written description of any third party claim against the
Indemnified Party, stating the nature and basis of such claim and, if
ascertainable, the amount thereof. The Indemnifying Party shall have a period of
thirty

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(30) days after receipt of such notice within which to respond thereto or, in
the case of a third party claim which requires a shorter time for response, then
within such shorter period as specified by the Indemnified Party in such notice
(the "Notice Period"). If the Indemnifying Party denies liability or fails to
respond to the notice within the Notice Period, the Indemnified Party may defend
or compromise the claim as it deems appropriate without prejudice to any of the
Indemnified Party's rights hereunder, with no further obligation to inform the
Indemnifying Party of the status of the claim and no right of the Indemnifying
Party to approve or disapprove any action, taken in connection therewith by the
Indemnified Party. If the Indemnifying Party accepts liability, it shall so
notify the Indemnified Party within the Notice Period and elect either: (i) to
undertake the defense or compromise of such third party claim with counsel
selected by the Indemnifying Party and reasonably approved by the Indemnified
Party, or (ii) to instruct the Indemnified Party to defend or compromise such
claim. If the Indemnifying Party undertakes the defense or compromise of such
third party claim, the Indemnified Party shall be entitled, at its own expense,
to participate in such defense. No compromise or settlement of any third party
claim shall be made without reasonable notice to the Indemnified Party and,
unless such compromise or settlement includes a general release of the
Indemnified Party in respect of the matter with no admission of liability on the
part of the Indemnified Party and non constraints on the future conduct of its
business, without the prior written approval of the Indemnified Party.

9.2Further Assurances:    After Closing, Seller and Purchaser agree to take such
further actions and to execute, acknowledge and deliver all such further
documents that are necessary or useful in carrying out the purposes of this
Agreement or of any document delivered pursuant hereto.

9.3Recording:    Purchaser shall, at its own cost, immediately record the
Assignment(s) in the appropriate offices of the state and county in which the
lands covered by the Assignment(s) are located. Purchaser shall immediately file
for and obtain all requisite approvals of any federal or state governmental
agencies to the Assignment(s) of the Assets. The Assignment(s) of any state or
federal oil and gas leases shall be filed in the appropriate governmental
offices on a form required and in compliance with the applicable rules of such
governmental agencies. Purchaser shall supply Seller with a true and accurate
photocopy of all the recorded and filed Assignment(s) within a reasonable period
of time after their recording and filing.

9.4Confidentiality :    Seller and Purchaser have previously executed a
confidentiality agreement covering the Assets (the "Confidentiality Agreement").
Until completion of the Closing (and, without limitation, in the event Closing
should not occur for any reason), the Confidentiality Agreement shall remain in
full force and effect. If the Closing occurs, the Confidentiality Agreement
shall terminate except with respect to any Licensed Data (as defined therein)
for which Purchaser has not acquired a license from the owner of such data.

9.5Agreement Regarding Certain Pending Litigation:    Macquarie Bank Limited
(parent entity of Seller) previously initiated Case No. 2007-C-134 in the
District Court, McKenzie County, North Dakota, against Bear Paw Energy LLC,
Novus Operating Company LP, LexMac Energy LP, et al (Novus and LexMac are
predecessors in interest to Seller) to assert rights to obtain payment of
suspended proceeds from production of gas from the Ann No. 1 well, McKenzie
County, North Dakota. The lawsuit is pending and has not been resolved. Bear Paw
continues to suspend and hold revenue from gas sold from the Ann #1 well prior
to the Effective Date and asserts a claim against Seller, as successor to LexMac
and Novus, for certain amounts owed to Bear Paw for a "pipeline connection fee"
for the Ann #1 well in connection with labor and materials costs for
installation of a gas flowline consisting of 847.6 feet of 4" steel pipe plus
metering facilities (the "Flowline"). Seller hereby agrees to retain all
obligation and liability for, and to indemnify, defend and hold Purchaser
harmless from any and all liability in connection with, the foregoing described
litigation and Seller shall be entitled to keep any production proceeds or other
awards granted to Seller in connection with the litigation.

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X.

TAXES

10.1Apportionment of Ad Valorem and Property Taxes:    All ad valorem taxes,
real property taxes, personal property taxes and similar obligations with
respect to the Assets for the tax period in which the Effective Date occurs
shall be apportioned as of the Effective Date between Seller and Purchaser. That
portion of such apportioned tax liability which is attributable to Seller shall
be credited to Purchaser's account. Purchaser shall file or cause to be filed
all required reports and returns incident to such taxes and shall pay or cause
to be paid to the taxing authorities all such taxes relating to the tax period
in which the Effective Date occurs. Purchaser shall supply Seller with copies of
the filed reports and proof of payment promptly after filing and paying them.

10.2Sales Taxes, Filing Fees, Etc.:    The Purchase Price and the Adjusted
Purchase Price provided for herein are net of any sales taxes or other transfer
taxes in connection with the sale of the Assets. Purchaser shall be liable for
any sales tax or other transfer tax, as well as any applicable conveyance,
transfer and recording fees and real estate transfer stamps or taxes imposed on
the transfer of the Assets pursuant to this Agreement. If Seller is required by
applicable state law to report and pay these taxes and/or fees, Purchaser shall,
upon presentment of an invoice by Seller, promptly deliver a check to Seller in
full payment of the invoice. Purchaser shall defend, indemnify and hold Seller
harmless with respect to the payment of any of those taxes including any
interest or penalties assessed thereon.

10.3Other Taxes:    All production, severance, excise, and other similar such
taxes or fees (other than income taxes) relating to production of oil, gas and
condensate attributable to the Assets prior to the Effective Date shall be paid
by Seller, and all such taxes relating to such production on and after the
Effective Date shall be paid by Purchaser. Purchaser shall supply Seller with
copies of the filed reports and proof of payment promptly after filing and
paying them.

XI.

INDEPENDENT INVESTIGATION AND DISCLAIMER

Purchaser acknowledges that it has had access to the Assets, the officers,
employees and agents of Seller, and the books, records and files of Seller
relating to the Assets, and in making the decision to enter into this Agreement
and consummate the transactions contemplated hereby, Purchaser has relied solely
on the basis of its own independent investigation of the Assets and upon the
representations and covenants in this Agreement. Accordingly, Purchaser
acknowledges that Seller has not made, AND SELLER HEREBY EXPRESSLY DISCLAIMS AND
NEGATES ANY REPRESENTATION OR WARRANTY, EXPRESS OR IMPLIED, AS TO: (a) THE
CONDITION OF THE ASSETS, INCLUDING, WITHOUT LIMITATION, ANY IMPLIED OR EXPRESS
WARRANTY OF MERCHANTABILITY, OF FITNESS FOR A PARTICULAR PURPOSE, OR OF
CONFORMITY TO MODELS OR SAMPLES OF MATERIALS AND ANY WARRANTY AGAINST HIDDEN
VICES OR DEFECTS; (b) ANY INFRINGEMENT BY SELLER OF ANY PATENT OR PROPRIETARY
RIGHT OF ANY THIRD PARTY; AND, (c) ANY INFORMATION, DATA OR OTHER MATERIALS
(WRITTEN OR ORAL) FURNISHED TO PURCHASER BY OR ON BEHALF OF SELLER, INCLUDING
WITHOUT LIMITATION, THAT RELATED TO OR BEARING ON THE EXISTENCE OR EXTENT OF
OIL, GAS OR OTHER MINERAL RESERVES, THE RECOVERABILITY OF OR THE COST OF
RECOVERING ANY SUCH RESERVES, THE VALUE OF SUCH RESERVES, ANY PRODUCT PRICING
ASSUMPTIONS, AND THE ABILITY TO SELL OIL OR GAS PRODUCTION AFTER CLOSING;
provided, however, that the foregoing disclaimer and negation of representations
and warranties shall not affect or impair the representations of Seller as set
forth in Article VI hereof.

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XII.

[RESERVED]

XIII.

MISCELLANEOUS

13.1Governing Law:    This Agreement shall be governed by and interpreted in
accordance with the laws of the State of Texas. All assignments and instruments
executed in accordance with this Agreement shall be governed by and interpreted
in accordance with the laws of the state where the Assets conveyed thereby are
located.

13.2Entire Agreement:    This Agreement, together with any confidentiality
agreements relating to the Assets previously executed by Purchaser, constitute
the entire agreement between the parties and supersede all prior agreements,
understandings, negotiations and discussions, whether oral or written, of the
parties. No supplement, amendment, alteration, modification, waiver or
termination of this Agreement shall be binding unless executed in writing by the
parties hereto.

13.3Waiver:    No waiver of any of the provisions of this Agreement shall be
deemed or shall constitute a waiver of any other provisions hereof (whether or
not similar), nor shall such waiver constitute a continuing waiver unless
otherwise expressly provided.

13.4Captions:    The captions in this Agreement are for convenience only and
shall not be considered a part of or affect the construction or interpretation
of any provision of this Agreement.

13.5Assignment:    Neither party hereto shall assign this Agreement or any of
its rights or obligations hereunder without the prior written consent of the
other party, and any assignment made without such consent shall be void. Except
as otherwise provided herein, this Agreement shall be binding upon and inure to
the benefit of the parties hereto and their respective permitted successors and
assigns.

13.6Notices:    Any notice provided or permitted to be given under this
Agreement shall be in writing, and may be served by personal delivery or by
depositing same in the United States mail, addressed to the party to be
notified, postage prepaid, and registered or certified with a return receipt
requested. Notices deposited in the mail in the manner hereinabove described
shall be deemed to have been given and received upon the date of delivery as
shown on the return receipt. Notice served in any other manner shall be deemed
to have been given and received only if and when actually received by the
addressee. For purposes of notice, until receipt of written notice changing
same, the addresses of the parties shall be as follows:

Seller's Mailing Address

One Allen Center
500 Dallas Street, Suite 3250
Houston, TX 77002

Attention: Mike Sextro

Purchasers Mailing Address:

1625 Broadway, Suite 250
Denver, CO 80202
c/o Michael Murray

13.7Waiver of Jury Trial:    SELLER AND PURCHASER DO HEREBY IRREVOCABLY WAIVE,
TO THE FULLEST EXTENT PERMITTED BY LAW, AND ANY AND ALL RIGHT TO A TRIAL BY

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JURY IN ANY ACTION, SUIT OR OTHER LEGAL PROCEEDING BASED UPON, ARISING OUT OF,
OR RELATING TO THIS AGREEMENT OR THE TRANSACTIONS CONTEMPLATED HEREBY.

13.8Limitation of Liability:    NOTWITHSTANDING ANYTHING HEREIN PROVIDED TO THE
CONTRARY, SELLER AND PURCHASER DO HEREBY COVENANT AND AGREE THAT THE RECOVERY BY
EITHER PARTY HERETO OF ANY DAMAGES SUFFERED OR INCURRED BY IT AS A RESULT OF ANY
BREACH BY THE OTHER PARTY OF ANY OF ITS COVENANTS, AGREEMENTS, REPRESENTATIONS,
GUARANTIES, WARRANTIES, DISCLAIMERS, WAIVERS OR CONTINUING OBLIGATIONS UNDER
THIS AGREEMENT SHALL BE LIMITED TO THE ACTUAL DAMAGES SUFFERED OR INCURRED BY
THE NON-BREACHING PARTY AS A RESULT OF SUCH BREACH, AND IN NO EVENT SHALL SUCH
RECOVERY INCLUDE ANY INDIRECT, CONSEQUENTIAL, EXEMPLARY OR PUNITIVE DAMAGES.

13.9Jurisdiction and Venue.    THE PARTIES HEREBY IRREVOCABLY SUBMIT TO THE
NON-EXCLUSIVE JURISDICTION OF ANY TEXAS STATE COURT OR FEDERAL COURT OF THE
UNITED STATES OF AMERICA SITTING IN HARRIS COUNTY, TEXAS, AND ANY APPELLATE
COURT FROM ANY THEREOF, WITH RESPECT TO ANY ACTION OR PROCEEDING ARISING OUT OF
OR RELATING TO THIS AGREEMENT AND CONSENT TO THE SERVICE OF PROCESS IN ANY
MANNER PERMITTED BY LAW.

13.10Books and Records:    Seller shall, at or as promptly as reasonably
possible after Closing, deliver the Data to Purchaser. Seller shall be entitled
to keep copies of the Data made at Seller's expense.

13.11Third Party Beneficiaries:    Neither this Agreement, nor any performance
hereunder by Seller or Purchaser, shall be deemed or interpreted to create any
right, claim, cause of action, or remedy on behalf of any person not a party
hereto.

13.12Expenses:    Except as otherwise provided herein, each party shall be
solely responsible for all expenses incurred by it in connection with this
transaction, including without limitation, fees and expenses of its own legal
counsel and accountants.

13.13Severability:    If any term or other provision of this Agreement is
invalid, illegal or incapable of being enforced under any applicable rule or
law, all other conditions and provisions of this Agreement shall nevertheless
remain in full force and effect so long as the economic or legal substance of
the transaction contemplated hereby is not affected in a materially adverse
manner with respect to either party.

13.14Survival:    Except as otherwise specifically provided in this Agreement,
all covenants, agreements, representations, guaranties, warranties, disclaimers,
waivers and continuing obligations shall survive the execution of the Agreement,
the Closing, and the delivery and recording of any deeds, assignments or bills
of sale which convey title to the Assets from Seller to Purchaser.

13.15Listing of Exhibits:    The Exhibits listed below are attached to this
Agreement and by this reference are fully incorporated herein:

Exhibit "A"—Description of Leasehold Interests
Exhibit "B"—Form of Assignment

13.16Counterparts:    This Agreement may be executed in one or more
counterparts, each of which shall be deemed an original, but all of which shall
constitute one and the same instrument.

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        IN WITNESS WHEREOF, the parties have executed this Agreement as of the
day and year first set forth above.

WITNESSES:   SELLER (Dual Signatures Required for Seller):
 
 
Macquarie Barnett, LLC

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By:
 
/s/ PAUL B. BECK

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    Name: Paul B. Beck

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    Title: Manager

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By:
 
/s/ RAYMOND WEEMS  

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    Name: Raymond Weems

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    Title: Manager
 
 
PURCHASER:
 
 
Kodiak Oil & Gas (USA) Inc.

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By:
 
/s/ LYNN A. PETERSON  

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    Name: Lynn A. Peterson

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    Title: President & CEO

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EXHIBIT "A"

Attached to and made a part of the Purchase and Sale Agreement
by and between Macquarie Barnett, LLC, as Seller, and
Kodiak Oil & Gas (USA) Inc., as Purchaser, dated March 31, 2010.

Description of Leasehold Interests

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EXHIBIT "B"

Attached to and made a part of the Purchase and Sale Agreement
by and between Macquarie Barnett, LLC, as Seller, and
Kodiak Oil & Gas (USA) Inc., as Purchaser, dated March 31, 2010.

Form of Assignment

ASSIGNMENT OF OIL AND GAS LEASES

STATE OF NORTH DAKOTA
COUNTY OF McKENZIE

THIS ASSIGNMENT is executed and made effective this 31st day of March (the
"Effective Time"), by and between:

Macquarie Barnett, LLC, a Delaware limited liability company, whose address is
One Allen Center, 500 Dallas Street, Suite 3520, Houston, Texas 77002,
hereinafter referred to as "Assignor," and Kodiak Oil & Gas (USA) Inc., whose
address is 1625 Broadway, Ste. 250 Denver, CO 80202, hereinafter referred to as
"Assignee",

W I T N E S S E T H: That,

For and in consideration of One Hundred ($100.00) Dollars and other good and
valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, Assignor, subject to the other terms, conditions, reservations and
limitations set forth herein, does, by these presents, bargain, sell, convey,
assign, grant, transfer, set over and deliver unto Assignee all of Assignor's
right, title and interest in and to the oil and gas leases (the "subject
leases") set forth on Exhibit "A", attached hereto and made a part hereof, and
all wells, equipment, facilities and other property and rights appurtenant
thereto, insofar as the same constitute part of the Assets (as this term is
defined in the Purchase and Sale Agreement, as defined below) (all the foregoing
being herein collectively referred to as the "Properties").

TO HAVE AND TO HOLD the Properties unto Assignee and its successors and assigns
forever.

It is agreed by Assignor and Assignee that this Assignment is subject to the
following terms and conditions:

1.This Assignment is made subject to that certain Purchase and Sale Agreement
dated of even date herewith, between Assignor and Assignee ("Purchase and Sale
Agreement"), and all terms and conditions of said Purchase and Sale Agreement
are incorporated herein by reference to the same extent and with the same effect
as if copied in full herein.

2.THIS ASSIGNMENT IS EXECUTED WITHOUT ANY WARRANTY OF TITLE WHATSOEVER, EITHER
EXPRESS OR IMPLIED, AND WITHOUT RECOURSE AGAINST ASSIGNOR, EVEN FOR THE RETURN
OF THE PURCHASE PRICE, BUT WITH FULL SUBSTITUTION AND SUBROGATION TO ALL RIGHTS
AND ACTIONS OF WARRANTY AGAINST ALL FORMER OWNERS AND VENDORS. AS TO ALL
EQUIPMENT, WELLS AND MOVABLE PROPERTY HEREIN CONVEYED, ASSIGNOR AND ASSIGNEE
AGREE AND UNDERSTAND THAT THIS ASSIGNMENT IS MADE "AS IS, WHERE IS," WITHOUT ANY
WARRANTY WHATSOEVER, EXPRESS OR IMPLIED, INCLUDING ANY IMPLIED WARRANTY OF
MERCHANTABILITY OR FITNESS FOR A PARTICULAR USE.

3.Assignee hereby assumes all duties, liabilities and obligations, express or
implied, imposed upon Assignor under the provisions of the subject leases, the
subject servitudes, the subject surface leases and all other contracts,
agreements and instruments affecting the Properties, whether recorded or
unrecorded, and under all applicable laws, rules, regulations, orders and
ordinances; and Assignee agrees to reimburse Assignor for any and all costs,
expenses, losses and damages of

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any kind or character sustained by it as a result of any failure of Assignee to
perform such obligations as more fully set forth in the Purchase and Sale
Agreement, including, but not limited to the Assumed Liabilities (as defined in
the Purchase and Sale Agreement).

4.Assignee agrees that it will not assign, sublease or transfer, in whole or
part, any rights acquired herein or by virtue of the above identified Purchase
and Sale Agreement without requiring its assignees, sublessees, and transferees
to expressly assume all obligations owed to Assignor under the terms of this
assignment and the Purchase and Sale Agreement, and all such pertinent terms
shall be incorporated into any and all future instruments translative of title.
Any assignment, sublease or transfer executed in contravention of this provision
shall be null and void.

5.Notwithstanding Assignee's right to assign all or part of the Properties to
third parties as conditioned by Paragraph 4 above, Assignee shall remain fully
responsible and liable for fulfillment of all the obligations and liabilities
imposed herein, and for compliance with all terms and conditions established
herein, and in the Purchase and Sale Agreement, whether express or implied.

6.ASSIGNEE AGREES TO INDEMNIFY, DEFEND AND HOLD HARMLESS ASSIGNOR, ITS OFFICERS,
DIRECTORS, EMPLOYEES, AGENTS, REPRESENTATIVES AND AFFILIATED OR PARENT COMPANIES
FROM AND AGAINST ANY AND ALL CLAIMS, LIABILITIES, LOSSES, CAUSES OF ACTION,
DAMAGES, LIENS, PENALTIES, SETTLEMENTS, JUDGMENTS, COSTS AND EXPENSES, INCLUDING
ATTORNEY'S FEES AND COURT COSTS, IN ANYWISE ARISING, GROWING OUT OF,
ATTRIBUTABLE TO OR RESULTING FROM ASSIGNEE'S OWNERSHIP OR OPERATION OF, OR
ACTIVITIES ON THE PROPERTIES, INCLUDING, BUT NOT LIMITED TO, ALL ASSUMED
LIABILITIES AND OTHER CLAIMS FOR DAMAGE TO PROPERTY OR INJURY OR DEATH TO
PERSONS, ALL AS MORE FULLY SET FORTH AND DEFINED IN THE ABOVE REFERENCED
PURCHASE AND SALE AGREEMENT, REGARDLESS OF THE SOLE, JOINT OR CONCURRENT
NEGLIGENCE, STRICT LIABILITY, BREACH OF CONTRACT OR OTHER FAULT OR
RESPONSIBILITY OF SELLER OR ANY OTHER PERSON OR PARTY, AND REGARDLESS OF WHETHER
KNOWN OR UNKNOWN, RELATING TO ACTIONS, EVENTS OR CONDITIONS EXISTING OR
OCCURRING PRIOR TO OR AFTER THE EFFECTIVE TIME, AND REGARDLESS OF WHETHER
ASSERTED UNDER ANY THEORY OF LIABILITY.

7.This Assignment shall be binding upon and inure to the benefit of the parties
hereto and their respective heirs, assigns, successors and transferees.

8.This instrument may be signed in any number of counterparts, each of which
shall be binding upon the party or parties so signing regardless of whether all
parties join herein.

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        IN WITNESS WHEREOF, this instrument is executed before the undersigned
competent witnesses as of this 31st day of March, 2010, but effective for all
purposes as of the Effective Time.

WITNESSES:   ASSIGNOR (Dual Signatures Required):           Macquarie
Barnett, LLC                                               
                                     By:                                       
                                         Name: Paul B. Beck
Title: Manager                                               
                                     By:                                       
                                         Name: Raymond Weems
Title: Manager             WITNESSES:   ASSIGNEE:           Kodiak Oil & Gas
(USA) Inc.                                               
                                     By:                                       
                                         Name:
Title:                                               
                                      

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STATE OF TEXAS
COUNTY OF HARRIS

        On this 31st day of March, 2010, before me appeared Paul B. Beck, to me
personally known, who, being by me duly sworn, did say that he is Manager of
Macquarie Barnett, LLC, a Delaware limited liability company, and that the
foregoing instrument was executed on behalf of said limited liability company,
and said Appearer acknowledged said instrument to be the free act and deed of
said limited liability company.

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NOTARY PUBLIC

My commission is for life.

STATE OF                         
COUNTY OF                         

        On this 31st day of March, 2010, before me appeared Raymond Weems, to me
personally known, who, being by me duly sworn, did say that he is Manager of
Macquarie Barnett, LLC, a Delaware limited liability company, and that the
foregoing instrument was executed on behalf of said limited liability company,
and said Appearer acknowledged said instrument to be the free act and deed of
said limited liability company.

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NOTARY PUBLIC

My commission is for life.

STATE OF                         
COUNTY OF                         

        On this 31st day of March, 2010, before me appeared
                                    , to me personally known, who, being by me
duly sworn, did say that he is the                                      of
Kodiak Oil & Gas (USA) Inc., a Colorado corporation, and that the foregoing
instrument was executed on behalf of said corporation by authority of its Board
of Directors, and said Appearer acknowledged said instrument to be the free act
and deed of said corporation.

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NOTARY PUBLIC

My commission expires:                         

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EXHIBIT "A"

Attached to and made a part of that certain Assignment of Record Title Interest
by and between Macquarie Barnett, LLC, as Assignor, and
Kodiak Oil & Gas (USA) Inc., as Assignee, dated March 31, 2010.

Description of Leasehold Interests

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QuickLinks

Exhibit 10.1

PURCHASE AND SALE AGREEMENT
RECITALS
EXHIBIT "A"
EXHIBIT "B"
Form of Assignment
ASSIGNMENT OF OIL AND GAS LEASES
EXHIBIT "A"
Attached to and made a part of that certain Assignment of Record Title Interest
by and between Macquarie Barnett, LLC, as Assignor, and Kodiak Oil & Gas (USA)
Inc., as Assignee, dated March 31, 2010. Description of Leasehold Interests