Capitalized Exploratory Well Costs

We capitalize exploratory well costs until a determination is made that the well has found proved reserves or is deemed noncommercial. If a well is deemed to be noncommercial, the well costs are charged to exploration expense as dry hole cost.

Changes in capitalized exploratory well costs are as follows and exclude amounts that were capitalized and subsequently expensed in the same period:



(millions)	Three Months Ended March 31, 2015
Capitalized Exploratory Well Costs, Beginning of Period	$	1,337
Additions to Capitalized Exploratory Well Costs Pending Determination of Proved Reserves	59
Reclassified to Proved Oil and Gas Properties Based on Determination of Proved Reserves	(6		)
Capitalized Exploratory Well Costs Charged to Expense ⁽¹⁾	(17		)
Capitalized Exploratory Well Costs, End of Period	$	1,373

⁽¹⁾ Relates to onshore US exploration activity.

The following table provides an aging of capitalized exploratory well costs based on the date that drilling commenced, and the number of projects that have been capitalized for a period greater than one year:



(millions)	March 31, 2015		December 31, 2014
Exploratory Well Costs Capitalized for a Period of One Year or Less	$	272	$	247
Exploratory Well Costs Capitalized for a Period Greater Than One Year Since Commencement of Drilling	1,101		1,090
Balance at End of Period	$	1,373	$	1,337
Number of Projects with Exploratory Well Costs That Have Been Capitalized for a Period Greater Than One Year Since Commencement of Drilling	13		13

The following table includes exploratory well costs that have been capitalized for a period greater than one year since the commencement of drilling as of March 31, 2015:




(millions)	Total by Project		Progress
Country/Project:
Onshore US
Northeast Nevada	$	26	Analyzing results from our first four exploratory vertical wells and evaluating potential for production tests.
Deepwater Gulf of Mexico
Troubadour	47		Evaluating development scenarios for this 2013 natural gas discovery including subsea tieback to existing infrastructure.
Offshore Equatorial Guinea (Blocks O and I)
Diega/Carmen	221		Evaluating regional development scenarios for this 2008 crude oil discovery. We drilled subsequent appraisal wells. During 2014, we conducted additional seismic activity over Blocks O and I and are engaged in processing the newly-acquired seismic data.
Carla	154		Evaluating regional development scenarios for this 2011 crude oil discovery. We drilled subsequent appraisal wells. During 2014, we conducted additional seismic activity over Blocks O and I and are engaged in processing the newly-acquired seismic data.
Felicita	39		Evaluating regional development plans for this 2008 condensate and natural gas discovery. A natural gas development team is working with the governments of Equatorial Guinea and Cameroon to evaluate natural gas monetization options and finalize a data exchange agreement between the two countries.
Yolanda	20		Evaluating regional development plans for this 2007 condensate and natural gas discovery. A natural gas development team is working with the governments of Equatorial Guinea and Cameroon to evaluate natural gas monetization options and finalize a data exchange agreement between the two countries.
Offshore Cameroon
YoYo	48		Working with the government to assess commercialization of this 2007 condensate and natural gas discovery. A natural gas development team is working with the governments of Equatorial Guinea and Cameroon to evaluate natural gas monetization options and finalize a data exchange agreement between the two countries.
Offshore Israel ⁽¹⁾
Leviathan	185		During 2014, we received the Leviathan Development and Production Leases, submitted a development plan to the government, completed substantial engineering and procurement activities and engaged in natural gas marketing activities.
Leviathan-1 Deep	79		Well did not reach the target interval; developing future drilling plans to test this deep oil concept, which is held by the Leviathan Development and Production Leases. We are working on potential well design and placement.



Dalit	28		Submitted a development plan to the government to develop this 2009 natural gas discovery as a tie-in to existing infrastructure.
Dolphin 1	25		Reviewing regional development scenarios for this 2011 natural gas discovery, including a potential tieback to Leviathan. We have applied to the Israeli government for a commerciality ruling.
Offshore Cyprus
Cyprus	203		Discussing monetization options with the Cyprus government for this 2011 natural gas discovery. In May 2014, our application for renewal of the PSC for two additional years was approved. We plan to submit a plan of development to the government in 2015.
Other
Individual Projects Less than $20 million	26		Continuing to drill and evaluate wells.
Total	$	1,101

⁽¹⁾ We are currently working to resolve antitrust and other regulatory matters with the Israeli government to enable Leviathan and other development to move forward. See Note 2. Basis of Presentation – Update on Core Area – Israel.