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    "wlbName" : "24/9-1",
    "wlbHistory" : "\r\n\u003cp\u003e\u003cb\u003eGeneral\u003c/b\u003e\u003c/p\u003e\r\n\r\n\u003cp\u003eWildcat well 24/9-1 is located in the\r\nVana Sub-basin in the Southern Viking Graben, about 11 km east of the border to\r\nBritish sector. The well was drilled to test a large, dip-closed structure\r\nlocated in the centre of the Viking Graben. The target was Late Jurassic\r\nsandstones. Two sandstone intervals were expected in the well, with a possible\r\ngross thickness of about 250-300 m. The prognosis was based on a correlation\r\nwith the UK wells 16/7-1, 16/8-1 and the Norwegian well 15/3-1 which are\r\nsituated in a similar position as 24/9-1 relative to the eastern boundary fault\r\nof the Viking Graben. \u003c/p\u003e\r\n\r\n\u003cp\u003eThe well is Reference Well for the\r\nSvarte, Tryggvason, Kyrre, and Jorsalfare Formations.\u003c/p\u003e\r\n\r\n\u003cp\u003e\u003cb\u003eOperations and results\u003c/b\u003e\u003c/p\u003e\r\n\r\n\u003cp\u003eWell 24/9-1 was spudded with the\r\nsemi-submersible installation Ross Rig on 29 February 1976 and drilled to TD at\r\n4907 m in the Late Jurassic Heather Formation. Below the 20" casing at\r\n758.3 m the Formations drilled contained abundant sand and was drilled\r\nextremely fast. This created problems as the solids removal system on the rig\r\nwas incapable of removing the sand as fast as it was drilled. In addition the\r\npolymer mud system chosen did not provide sufficient fluid loss control in the\r\nporous formation and large amounts of fluids were lost to the formation. From\r\nca 2440 m to TD at 2752 m in the 17 1/2" hole low penetration rates was a\r\nproblem. Of 126 rig days 20 % was counted as lost time, but the total time\r\nspent on the well was still less than the originally estimated 139 days. Problems\r\nrelated to tight/sloughing hole and down hole tool failure accounted for\r\nroughly half of the lost time. The well was drilled with seawater down to 256\r\nm, with lime / lignosulphonate from 256 m to 3983 m, with Dextrid /\r\nLignosulphonate from 3983 m to 4613 m, and with lime / lignosulphonate from\r\n4613 m to TD. \u003c/p\u003e\r\n\r\n\u003cp\u003eTertiary sandstones were encountered in\r\nthe Grid Formation (1131 m to 1420 m), The Heimdal Formation (2202 m to 2497\r",
    "wlbHistoryDateUpdated" : "2026-02-24T00:00:00"
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