period costs and partially carry Tullow’s share of a planned 3D seismic program (up to $2.1 million net to Kosmos). We will also pay Tullow $2.5 million by the end of the initial phase of the exploration period for additional carry of seismic and other joint account costs. Drilling of the Hippocampe-1 exploration well on the C8 block was completed in October 2017. Designed to test Lower Cenomanian and Albian reservoirs, the well was drilled to a total depth of approximately 5,500 meters. The well has been plugged and abandoned. Total well and other related costs of $31.3 million are included in exploration expenses in the accompanying consolidated statement of operations for the year ended December 31, 2017. In December 2017, the Lamantin-1 exploration well was drilled to a total depth of 5,150 meters. This well was designed to evaluate a previously untested Lower Campanian base of slope fan supplied from the Nouakchott River system, trapped in a combination structural-stratigraphic feature, and charged from underlying, oil-prone Cenomanian/Turonian and Albian source rocks. The well has been plugged and abandoned. Total well and other related costs of $8.0 million are included in exploration expenses in the accompanying consolidated statement of operations for the year ended December 31, 2017. In December 2017, we began a 3D seismic survey of approximately 9,400 square kilometers over Block C18 offshore Mauritania. Senegal In May 2017, we announced the Yakaar-1 exploration well, located in the Cayar Offshore Profond block offshore Senegal, made a major gas discovery. Located approximately 60 miles northwest of Dakar in approximately 2,600 meters of water, the Yakaar-1 exploration well was drilled to a total depth of approximately 4,900 meters. The well intersected a gross hydrocarbon column of 120 meters (394 feet) in three pools within the primary Lower Cenomanian objective and encountered 45 meters (148 feet) of net pay. An appraisal program over the combined Yakaar and Teranaga discoveries is progressing. In the second quarter of 2017, upon completion of an agreement between BP and Timis Corporation Limited (‘‘Timis’’) by which BP acquired Timis’ entire 30% participating interest in the Senegal Blocks, Kosmos agreed to withdraw the exercise of our call option to increase our equity in each of the Cayar Offshore Profond and the Saint Louis Offshore Profond blocks from 60% to 65% in exchange for carrying Timis Corporation’s paying interest share of a third well in either contract area, subject to a maximum gross cost of $120.0 million. In February 2018, the Requin Tigre-1 exploration well was drilled to a total depth of 5,200 meters and was designed to evaluate Cenomanian and Albian reservoirs in a structural-stratigraphic trap, charged from an underlying Neocomian-Valanginian source kitchen. The prospect was fully tested but did not encounter hydrocarbons. Post-well analysis is currently ongoing to determine the reasons it was unsuccessful. The well has been plugged and abandoned. Total well and other related costs of $0.4 million are included in exploration expenses in the accompanying consolidated statement of operations for the year ended December 31, 2017. Morocco (including Western Sahara) In November 2017, Kosmos provided to our co-venturers a notice of withdrawal from Boujdour Maritime and transferred its participating interest and operatorship to ONHYM. Certain transition services are being provided to ONHYM as part of the handover of operatorship. In order to complete our obligations under the petroleum contract, we will continue to fund the remainder of the current seismic program. 82