
	December 31, 2022					December 31, 2021
(Thousands of dollars)	Cost		Net			Cost		Net
Exploration and production ¹	$	20,567,489	$	8,204,463	2	$	20,440,568	$	8,098,396	2
Corporate and other	150,498		23,553			145,135		29,456
Property, plant and equipment	$	20,717,987	$	8,228,016		$	20,585,703	$	8,127,852
¹ Includes unproved mineral rights as follows:	$	476,981	$	344,507		$	615,724	$	131,107

During the third quarter of 2022, the Company completed the disposition of its 62.5% operated working interest of the Thunder Hawk field for a purchase price of $20.0 million less closing adjustments of $23.1 million, resulting in a total net payment to the buyer of $3.1 million. Additionally, the buyer assumed the asset retirement obligations of approximately $47.9 million. A $17.9 million gain on sale was recorded in the period related to the sale. In September 2022, the Company completed the disposition of the Block CA-2 asset in Brunei for contingent consideration valued at approximately $8.7 million. No gain or loss was recorded related to this sale.

In 2021, the Company sold its interest in the King’s Quay FPS to ArcLight Capital Partners, LLC (ArcLight) for proceeds of $267.7 million, which reimburses the Company for previously incurred capital expenditures.

In August 2022, the Company acquired an additional working interest of 3.37% in the Lucius field for a purchase price of $78.5 million, net of closing adjustments.

In June 2022, the Company acquired an additional working interest of 11.0% in the Kodiak field for a purchase price of $50.0 million, net of closing adjustments.

In 2021, the Company recorded an impairment charge of $171.3 million for Terra Nova due to the status, including agreements with the partners, of operating and production plans. Subsequently, the Company acquired an additional 7.525% working interest at Terra Nova following a commercial agreement to sanction an asset life extension project. The Company also recorded an impairment charge of $25.0 million for assets reported as Assets held for sale in the Consolidated Balance Sheet.


	December 31,
(Thousands of dollars)	2022		2021		2020
Canada	$	—	$	171,296	$	—
Other Foreign	—		18,000		39,709
Corporate	—		7,000		14,060
U.S.	—		—		1,152,515
	$	—	$	196,296	$	1,206,284

Under FASB guidance exploratory well costs should continue to be capitalized when the well has found a sufficient quantity of reserves to justify its completion as a producing well and the Company is making sufficient progress assessing the reserves and the economic and operating viability of the project.

At December 31, 2022, 2021 and 2020, the Company had total capitalized drilling costs pending the determination of proved reserves of $171.9 million, $179.5 million and $181.6 million, respectively. The following table reflects the net changes in capitalized exploratory well costs during the three-year period ended December 31, 2022.


(Thousands of dollars)	2022		2021		2020
Beginning balance at January 1	$	179,481	$	181,616	$	217,326
Additions pending the determination of proved reserves	33,440		16,725		3,999

Divestment	(7,915)		—		—
Capitalized exploration well costs charged to expense	(33,146)		(18,860)		(39,709)
Ending balance at December 31	$	171,860	$	179,481	$	181,616

The capitalized well costs charged to expense during 2022 represent expenditures related to the Cutthroat-1 exploration well in block SEAL-M-428 in the Sergipe-Alagoas Basin offshore Brazil and Hoffe Park #1 (Mississippi Canyon 122) in the Gulf of Mexico.

The following table provides an aging of capitalized exploratory well costs based on the date the drilling was completed for each individual well and the number of projects for which exploratory well costs has been capitalized. The projects are aged based on the last well drilled in the project.


	2022				2021				2020
(Thousands of dollars)	Amount		No. of Wells	No. of Projects	Amount		No. of Wells	No. of Projects	Amount		No. of Wells	No. of Projects
Aging of capitalized well costs:
Zero to one year	$	15,527	2	2	$	13,273	3	3	$	—	—	—
One to two years	13,307		2	2	—		—	—	54,220		5	5
Two to three years	—		—	—	53,070		5	5	—		—	—
Three years or more	143,026		5	4	113,138		6	—	127,396		6	—
	$	171,860	9	8	$	179,481	14	8	$	181,616	11	5

Of the $156.3 million of exploratory well costs capitalized more than one year at December 31, 2022, $96.3 million is in Vietnam, $37.1 million is in the U.S., $15.5 million is in Mexico, $4.7 million is in Canada and $2.7 million is in Brunei. In all geographical areas, either further appraisal or development drilling is planned and/or development studies/plans are in various stages of completion.