Suspended Wells and Exploration Expenses

12 Months Ended

Dec. 31, 2023

Extractive Industries [Abstract]

Suspended Wells and Exploration Expenses

Note 6—Suspended Wells and Exploration Expenses

The following table reflects the net changes in suspended exploratory well costs during 2023, 2022 and 2021:

	Millions of Dollars
	2023		2022	2021
Beginning balance	$	527	660	682
Additions pending the determination of proved reserves	—		5	10
Reclassifications to proved properties	(285)		(7)	—
Charged to dry hole expense	(58)		(131)	(32)
Ending balance	$	184	527	660

The following table provides an aging of suspended well balances at December 31:

	Millions of Dollars
	2023		2022	2021
Exploratory well costs capitalized for a period of one year or less	$	—	15	4
Exploratory well costs capitalized for a period greater than one year	184		512	656
Ending balance	$	184	527	660
Number of projects with exploratory well costs capitalized for a period greater than one year	14		17	22

The following table provides a further aging of those exploratory well costs that have been capitalized for more than one year since the completion of drilling as of December 31, 2023:

	Millions of Dollars
			Suspended Since
	Total		2020-2022	2017-2019	2006-2016
WL4-00—Malaysia(2)	36		19	17	—
PL891—Norway(1)	30		30	—	—
West Willow—Alaska(1)	29		—	29	—
Narwhal Trend—Alaska(1)	25		—	25	—
PL782S—Norway(1)	19		—	19	—
Montney—Canada(1)	16		8	8	—
Other of $10 million or less each(1)(2)	29		—	4	25
Total	$	184	57	102	25

(1)Additional appraisal wells planned.

(2)Appraisal drilling complete; costs being incurred to assess development.

Exploration Expenses

The charges discussed below are included in the “Exploration expenses” line on our consolidated income statement.

2023

In our Europe, Middle East and North Africa segment, after further evaluation we recognized a before-tax expense of $37 million for dry hole costs associated with the suspended Warka discovery well, drilled in 2020, on license PL1009 in the Norwegian Sea.

In our Alaska segment, we recorded a before-tax expense of approximately $31 million for dry hole costs associated with the Bear-1 exploration well.

2022

In the fourth quarter, we recorded a before-tax expense of $129 million for impairment of certain aged, suspended wells associated with Surmont in our Canada segment.

In our Europe, Middle East and North Africa segment, we recorded a before-tax expense of $102 million for dry hole costs associated with four operated exploration and appraisal wells and one partner-operated well that were drilled in Norway in 2022.