. Transactions of the Royal Society of New Zealand. ; basalt inclusions, 25 mm. by 30 mm. ; noncrystallineinclusions, 75 mm. by 40 mm. The thickness of the breccia is rather difficult to determine,but at least 100 yards across the strike is exposed here, whichat an average dip of 26° gives a minimum thickness of 130 north, along the beach, the dip changes to the oppositedirection, showing evidently a synclinal curve. The barrenbreccia also varies considerably in dip, and appears to forman anticline. It is slightly faulted at one place, the displace-ment being 18 in. to the northward
. Transactions of the Royal Society of New Zealand. ; basalt inclusions, 25 mm. by 30 mm. ; noncrystallineinclusions, 75 mm. by 40 mm. The thickness of the breccia is rather difficult to determine,but at least 100 yards across the strike is exposed here, whichat an average dip of 26° gives a minimum thickness of 130 north, along the beach, the dip changes to the oppositedirection, showing evidently a synclinal curve. The barrenbreccia also varies considerably in dip, and appears to forman anticline. It is slightly faulted at one place, the displace-ment being 18 in. to the northwards, and the hade of the fault60° N. Near the fault is a fissure, filled evidently from abovewith the materials that form the mineral breccia ; thisfilling, withstanding erosion a little better than the barrenbreccia, stands out like a dyke. Similar vertical cracks in atuff at Oamaru are filled with limestone, and at first sight seemto be vertical beds of limestone. The barren breccia be-comes flatter to the northwards in its upper layers, the dip. IV. Sketch-plan of Outcrops of MineralBreccia on the Beach, North Head, Ka-kanui, SHOWING PERICLINAL FOLD. 488 Transactions. being 14° at its contact with the fine tuff. The top layer, asstated, is fossiliferous, and appears to have formed the sea-bottom for a sufficient time to permit of a growth of corals. The chief fossils found here were : Corals—Flabellum cir-culare and other species ; Trochocyathus, sp. ; Ddtocyathus, sp. ;Amphihelia intricata; and Graphularia, sp. Brachiopods —Magellania lenticularis and M. sinuata; Liothyrina, n. sp. ;Notothyris suessi ; Terebratella gualteri; and Rhynconella squa-mosa. Scaphopods—Dentalium mantdli. Gasteropods—Scalariabrownii; Siphonalia nodosa ; Mitra, sp. ; Gibbula, sp. ; Turbo,n. sp. ; Natica, sp. Lamellibranchs—Cardtta, n. sp. ; and Pectensectus. Cephaloppds—Nautilus, sp. The fine micaceous tuffs are poor in fossils, and apparentlyrepresent a period during which the ocean-fl
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectscience, bookyear1905
