174

EXCURSION TO AND NEWBURY.

SATURDAY, APRIL 17TH, 1909. Directors .. LL. TREACHER, F.G.S., AND H. J. OSBORNE WHITE, F.G.S.

Excursion Secretary .. MISS M. S. JOHNSTON.

(RFport by H. J. OSBORNE WHITE.)

THE party, fourteen in number, met at Burghclere Station at 2.20 p.m., and, after glancing at the adjacent shallow railway cut­ ting, which shows the green sands of the Pecten asper Zone dipping gently southward from the axis of the Kingsclere anticline, drove eastward along the Road-some in a brake, others in a motor-car. About a quarter of a mile east of the station the road crosses a small valley worn in the Upper Greensand, and here the mem­ bers alighted in order to inspect a field-pit opened on the western side of this feature, and to the north of the road. The excavation shows about ten feet of irregularly-jointed light-grey sandstone, containing bands of grey nodular chert. A few fossils (including Pecten (Syncyc!onema) orbicularis, Ostrea sp., and echinid spines) were found, but nothing zonally distinctive. The beds here are, however, clearly on a lower horizon than those seen in the cutting north of Burghclere Station, and probably belong to the zone of Schloenbac1zia rostrata. The next stop was made at Werg's Farm, whence a good view can be had of the main features of the Kingsclere Vale. At this point the Directors gave a short account of the local geology and physiography, illustrating their remarks with diagrams. At the quarry near Portridge Cottages, in the westernmost of the four gaps in the Chalk ridge which forms the northern rim of the vale, some time was spent in examining the section described on p. 25 of the Geological Survey Memoir on the Andover dis­ trict. The descending succession here is :- Feet. Zone of 5· White chalk with flints; Mieraster prcecu,'sor ! (with" sub-divided" interporiferous areas) %1. cor-testudinarium. ) &c.. ...•.•. 18 4' Hard yellow chalk, with green-coated nodules at top ...... Zone of 3. Greyish nodular chalk; M prceeursor ("feebly Holaster planus. inflated" to " sutured" areas), &c.. . { 2. Chalk Rock, with two layers of green-coated nodules I' Zone of • Terebratuiina lata. { 1. Greyish nodular chalk, much obscured . 20 EXCURSION TO BURGHCLERE AND NEWBURY. 175

The beds dip northward at 26°. The junction of the II. planus and T. lata Zones has not been exactly located; it may occur a foot or two below the rather ill-defined top of bed (I) Most of the following fossils, found here on the day of the excursion, were collected by Mr. T. H. Withers:-

Bed 5. Micraster precursor, Rowe. Bed 4. Nautilus d. darupensis, Schliit (as a green-coated cast). Bed 3. *Parasmiiia aff.serpen­ Bourgueticrinus sp. tina, Edw. and Haime. *Berenicea phlyctcenosa, Reuss. Micraster cor-bovis, * regularis (d'Orb.) Forbes. var. gamNei, Greg. ---- precursor, *Stomatopora gracilis Rowe. (M. Edw.). Echinocorys scutatus, Terebratula semiglobosa, Leske. J. Sow. Holaster placenta, Spondylus spinosus, J. Sow. Agass. Bed I. Bourgueticrinus sp. Terebratulina lata, Eth. (rare) Serpula sp. t Inoceramus brongniarti, t Rhynchonella mantel­ J. de C. Sow. liana, J. de C. Sow.

Passing through the gap, and skirting Hockley's Hole spring near the junction of the Chalk and the Reading Beds, the party proceeded eastward along the ridge-way to the cross-roads south of Cowhouse Farm, where they paused to enjoy the fine outlook over the Kingsclere Vale. Seen from this point, the oval dome of Selbornian strata, rising with a bold curvature in the midst of the vale and dominating the Chalk ridge to the north of it, forms a striking feature in the landscape. The members then descended to the adjacent Cowhouse chalk-pit, on the northern slope of the ridge. and were able to verify the account of this section given in the PROCEEDINGS a few years ago. + The succession is :- Feet. Made ground and wash. .." " to 6 Zone of 1Soh white chalk, with few flints; Marsupites, Marsu ites, .&c. . '. . . . about 30 l' Similar chalk; Ulntacrlnus, &c . about 25 Zone of J White chalk, with flints; a band of pink flints at M. cor-anguinum. I the top; Conulus albogalerus, &c. •. seen 30 The bedding dips north-westward, at an angle of about 25°. It was remarked that the chalk at the junction of the Marsupites

• Identified by Mr. W. D. Lang. t Identified by Mr. R. Bullen Newton. t Vol. xix, '906, pp, 383, 384. PROC. GEOL. Assoc., VOL. XXf, PART 3, 19°9] 13 176 EXCURSION TO BURGHCLERE AND NEWBURY. and Uintacrinus Bands contained scarcely any remains of the characteristic crinoids. Resuming their seats in car and brake, the party were carried northward, across the undulating country of the Eocene Beds, to the southern border of Sydmonton , a pleasant little tract of woodland, which was traversed on foot. Near the middle of the common a group of pits among the trees showed 7 or 8 feet of stratified, ochreous flint-gravel, at about 350 feet a.D. From the fields east of House a good side-view was obtained of the gravel-capped plateau of Greenham. The even­ ness of its sky-line, and the form of the boggy gullies which furrow its heath-grown southern flanks, were well seen in the late-after­ noon light. The party crossed the River Enborne by Aldern footbridge, and gaining the summit of the plateau at the gravel-pit by Noah's Ark, were driven thence to St. John's Vicarage, Newbury, where they were hospitably entertained by Miss Wickham Legg. A vote of thanks to Miss Wickham Legg and the Directors was proposed by Mr. G. Potter, and the excursion terminated at Newbury Station shortly after 7 p.m.

REFERENCES. Geological Survey Map, 1 inch scale, new series, No. 283 (Andover) and No. 267 (Hungerford). 1826. BUCKLAND, W.-On the Formation of the Valley of Kingsclere, &c., Trans. Geol. Soc., ser. 2, vol, ii, p. H9. 1872. WHITAKER, W.-Geology of the London Basin. Mem. Geol. SurvlY, p. 12. 1879. JONES, T. RUPERT.-Excursion to Newbury. Proc, Geol, Assoc., vol. vi, p. 185. 1889. HERRIES, R. S.-Excursion to Newbury. Proc, Geol, Assoc., vol. xi, p. xiv, 1900. JUKES-BROWNE, A. J.-Cretaceous Rocks of Britain. Mfm. Geol. SU"VfY, vol. i, p. H3. 1902. \VHITE, B. J. OSBORNE.-On a peculiarity in the course of certain streams in the London and Hampsbire Basins. Proc. Geo!..Ils'oc., vol. xvii, p. 399. 19°4. JUKES-BROWNE, A. J.-Cretaceous Rocks of Britain. Mlm. Geol. Survey, vo l, iii, p. 184. 1906. TREACHER, LL., and H. J. OSBORNE WHITE.-The Higher Zones of the Upper Chalk in the western part of the London Basin. Proc, Geol. Assoc .. vol, xix, p. 383. 1907. WHITE, H. J. OSBORNE.-Geology of Hungerford, etc. Mem. Gco], Survey. pp. 3, 88-89,93· 1908. Jl"KES BROWNE, A. J. and others.-Geology of Andover. Mem. Geot. Survey, pp. 5-8, 1I-12, 25,31,34,41,58.