C—2c

12

should be extended nearly to the horizons at which the shoots were cut off. The bores should be so directed that they will not, at each of these horizons, be more than 200 ft. apart. It should bo noted that the lost part of the Progress shoot lies considerably to the north-west of tho Dam and Middle shoots and thus its position cannot economically be determined from bore-sites in Devil Creek. If, however, the position of any shoot of the Progress lode west of the fault should be determined the location of other shoots becomes simple.

6. THE CHERTSEY OIL-BORE. (By J. Henderson.) An account of the oil-bore near Chertsey Railway-station has already been given (see N.Z. Geol. Surv. 14 Ann. Rep., C.-2c, p. 8, 1920). The well was again visited on tho 15th and 16th September, 1921, and the following additional information obtained. The well had reached a depth of 2,170 ft. when quicksand showing a little thick, oil was penetrated, and rushed up the bore several hundred feet. This caused the company to abandon the well, and a general meeting of shareholders held on the 20th September passed a resolution that the affairs of the company bo wound up. When visited the 2§ in. casing had been withdrawn and the 4 in. casing was being cut. In all 230 tons of casing were used—namely, 181 in. casing to a depth of 220 ft., 16 in. to 319 ft. 14 in. to 680 ft., 1,2 in. to 895 ft., 10 in. to 1,050 ft., 9 in. to 1,220 ft., 71, in. to 1,185 ft., 6 in. to 1,605 ft., 5 in. to 2,067 ft., 4 in. to 2,132 ft., and 2J in. to 2,170 ft. Log of Chertsey Bore (10 ft. below railway-station level — 351 ft.). Drilled by the Canterbury p ce t. Petroleum Prospecting Company, 1914-21. 0- 319 Loose gravel and boulders; water-level at 230 ft.; at 190 ft., clay band with little water above. • 319- 515 Conglomerate gravels. 515- 534 Loose gravel; water-level at 230 ft. 534-1,056 Hard conglomerate gravel, cemented. 1,056-1,171 Clay and boulders. 1,171-1, .172 Loose gravel; water-level at 360 ft. 1,172-1,355 Gravel with large boulders. 1,355-1,368 Dark blue (clay?) with boulders. 1,368-1,370 Brown sand and clay showing gas (CO 2 ) and oil of tarry nature. 1,370-1,374 Sand and gravel; oil and gas (CO 2 ) ; "water-level at 360 ft. 1,374-1,387 Dark-coloured sandy clays. 1,387-1,396 Sand; gas (CO 2 ). 1,396-1,397 Dark-coloured sand showing heavy petroleum butter and inflammable gas. 1,397-1,420 Blue, clay with streaks of sandstone gravel. 1,420-1,423 Sand. 1,423-1,437 Clay and gravel. 1,437-1,443 Sandy gravel; gas and oil shows in sludge; water-level at 360 ft. 1,443-1,447 Brown clay. 1,447-1,456 Gravel; water-level at 360 ft. ; inflammable gas. 1,456-1,502 Clay mixed with gravel. 1,502-1,506 Sandy gravel; gas; water-level at 360 ft, 1,506-1,512 Clay and gravel. 1,512-1,524 Gravel with large boulders; water-level at 360 ft. ; gas. 1,524-1,605 Gravel mixed with clay. 1,605-1,690 Gravel with more clay in it. 1,690-1,695 Dark-coloured clay. 1,695-1,745 Hard conglomerate gravel; shows oil and gas. 1,745-1,782 Brown clay streaks, sand, and gravel; gas and oil. 1,782-1,812 Hard boulder conglomerate. 1,812-1,864 Brown sandstone grits, streaks clay, and sand; water-level at 360 ft. 1,864-1,905 Yellow clays showing streaks blue- and lighter-coloured clays. 1,905-1.998 Sandy and clayey conglomerate gravels. Hard blue clay. 2,025-2,028 Sandy brown clay. 2,028-2,040 Blue and yellow clay with large boulders. 2,040-2,111 Blue and yellow clay. 2,111-2,124 Hard blue clay. 2,124-2,130 Grey-blue quicksand. 2,130-2,170 Hard blue clay; below 2,170 ft. quicksand with gas (CO 2 ) and oil shows; runs in badly; water-level at 470 ft.(?)