TWO TUNNELS IN COLD ICE AT 4,000 m. ON THE BREITHORN By J OEL E. FISHER (New York) ABSTR ACT . A d escription is given of two tunnels, each 60- 70 m. long, one directl y a bove the o ther, a t 4,000 a nd 4,020 m . a.s.1. excavated throug h cold firn and ice of the Breithorn in the A lps. The tem pera ture rose from - 5' 50 C. at the portal to - o· 50 C. a t the rock interface 70 m. from the porta l in the upper tunnel, a nd from - 5' 50 C. to 00 C. at a water reservoir 60 m . from the porta l in the lower tunnel. In both cases cracks or minute sealed crevasses, cut by the tunnel, opera ted to cool the ice locally below the tempera ture to be expected from a smooth curve. Possible origins of the water reservoir a re d iscussed. Small a mounts of a ir a t a moderate pressure, enclosed in small, sealed cracks a nd hollows, were punctured between 60 a nd 70 m. from the portal in the upper tunnel. T he pungent od or of the air thus released was identified as ozone (a) by its cha racteristic odor, (b) by its reacti on on rubber, and (c) by potassium iodide starch paper tests. The so urcc of such ozone is suspected to be minute electric sparks resulting from sta ti c electric charges built up in cold ice when it is subjected under pressure to cracking or deforma ti o n ; photo­ graphs taken with expos ures of 8 hr. in the upper tunnel a t night appa rently show such sparks. A description is given of the appearance of cold ice, frozen to the bedrock, being forcibly tortured into streamers a ncl ba ncls by the movem ent of the cntire ice bocl y at 0·6 m. /yr. R ESU ME. O n d eerit 2 tunnels, ayant chacun de 60 it 70 m de long, places I' un a u-dessus d e I'autre it 4 000 et 4020 m d 'altitude qui ont ete creuses dans le neve froid et la glace clu Breithorn cl ans les Alpes. D ans le tunnel superieur, la tempera ture s'est eI evee cl e - 5,50 C it I'entree jusqu'it - 0,50 C a u contac t d e la roehe situee it 70 m: d ans le tunnel inferi elll', la temperature passe cl e - 5,50 C it 0 0 C it 60 m de I'entree, da ns un reservoir eI 'eau. D a ns les el eux cas, d es fi ssures ou d e petites crevasses refermees, coupees par le tunnel, ont refroieli la glace localement, en el essous d e la tempera ture que I'on a lll'ait pu attenelre it partir cl ' une cOlll'be reguliere. O n discute l'origine clu reservoir eI 'eau. De petites poehes d 'air occlus dans d e petites fentes e t creux refermes, ont ete percees entre 60 et 70 m it panir el e I'en tree dans le tunnel superieur. L'odeur piquante de I'air a insi libere a ete atlribuee it I'ozone : (a ) it cause cl e son oel eur caracteristique, (b) it cause d e sa reacti on sur le caoutchouc, et (c) par suite de tests effectues avec un pa pier amicl onne it I'iodure cl e potassium. O n suppose que I'existcnce cl e I'ozone es t due it de peti tes etincell es provenant d e cha rges electriques sta tiques creees d a ns la glace froide soum ise sous­ pression a ux craquem ents ou deformations; el es photogra phics prises avec des temps d 'exposition d e 8 heures, la nuit el ans le tunnel superi eur, montrent appa remment de tell es etincelles. On decrit I'aspect de la glace froide, gelee sur le lit rocheux, q ui es t deformee avec force en coura nts et baneles pa r suite d'un mouvement de 0,6 m pa r a n de la masse entiere el e glace. Z US AMMEN FASSUNG . Zwei Tunnels , j eel er 60- 70 m lang , einer unmittelbar liber cl em anderen in 4000 unci in 4020 m liber d em M eer, wurcl en dureh ka lten Firn und ka ltes Eis a m Breithorn in den Schweizer Alpen gegra ben. Eine entsprechencle Beschreibung wird gegebe n. Im oberen Tunnel stieg cli e T empera tur von - 5,50 C a m Porta l bis - 0,50 a n d er Felsgrenze 70 m vom Porta l entfernt. Im unteren Gletscher stieg die 0 T empera tur von - 5,5 a uf 0° bis zu einem VV asserreservoir, class 60 111 vom Porta l entfernt ist. In beiclen Fa llen unterklihlten Risse odeI' kleinc versc hl ossene Spalten , die clurch cl en Tunnel a ufgeschni tten wurcl en, ortlich das ka lte Eis unter cli e T emperatur, clie von einer a usg lcichenden Kurve erwa rtet w urde. Die l1logliche E ntstehung d es Wasse rreservoirs wircl diskutiert. Kleine Betrage von Luft, die unter massigem Druck steht. unci in kleinen verschl ossen en Rissen unci Lochern cingeschlossen ist, wurden in Entfernungen zwischen 60 unci 70 111 vom Porta l im oberen Tunnel angeschnittcn. De r stechende Geruch cl er Luft, cli e d adurch frei wurde, konnte als Ozon idel1lifi ziert werclen (a ) durch se inen charakteristisc hen G eruch, (b) clurch seine R ea ktion a uf K a utschuk und (c) clurch Ka lium J odid Stii rkepa pierteste. Es wircl vermutet, cl ass cli eses Ozon durch kl eine Funken entsteht, die von sta tischen Aufladungen herrlihren ; cli cse bauen si ch im ka lten Eis a uf, wenn es unter Druck Z UI1l Reissen gebracht ocl er defonniert wird. Photogra phisehe Aufnahmcn mit E xpositionszeiten von 8 Stunelen zcig ten im oberen Tunnel bci Nacht d eutlich offenbar solche Funken. Es wircl eine Beschreibung cl er Erscheinung von ka lten Eis gegeben, d as a m Felsunterg runcl a ngefroren ist unci durch die Bewegung cl cs ganzen Eiskorpers mit 0,6 mlJahr un ter sta rkstem Zwang so beansprucht wird, dass Stromlinien und Bander entstehcn. SOME 52 years ago, at Yale, the la te Professor Joseph Barrell brought to my a ttention a paper by Willard D . Johnson (1904) , Johnson described how he had descended into an open berg­ schrund on Mt. Lyell in the Sierras, and having noted in it copious melt water, cOUl'sing down its rock wa ll , yet that qua ntities of icicles fes tooned other parts of the na ked rock, he concluded that the rapid alternations of m elting and freezing to be found in such bergschrunds esta b­ lished bergschrunds in genera l as the specifi c cutting tool by which glacier cirques were created. 5' 3 Downloaded from https://www.cambridge.org/core. 23 Sep 2021 at 13:31:43, subject to the Cambridge Core terms of use. JOURNAL OF GLACIOLOGY It is to be noted at this point that even in the temperate Alps by far the greater part of the snow and ice areas- some 80 per cent in the Zermatt area, for example- is well above the firn line, and the nivi fields of such areas are necessarily " cold" ice- snow or ice which is, in substance, below 0° C. (actually, at the mean annual temperature of the atmosphere for the altitude under study) . It is to these areas of cold ice, bergschrunds or no bergschrunds, that one must look, in my opinion, to understand processes of cirque erosion, especially under former, more extensive glaciation. With this objective in mind, I had attempted in 1952 to excavate a tunnel through to bedrock in the cold nivi at the 4,000 m. contour, under the Silbersattel, on Monte Rosa in the Pennine Alps. A year later, after that first tunnel had advanced 50 m., the Silbersattel site had to be abandoned, due to increasing danger of ice falls to the crew. I then had a tunnel driven through the nivi on the nearby Sattel of Monte Rosa, elevation 4,20 0 m. ; this tunnel reached the rock interface (Fisher, 1955). The results from that project can be summarized as follows : that "Sattel" tunnel, 92 m. in length, penetrated nivi the temperature of which Horizontal s.cale in meters. 0 10 20 30 40 50 60 70 80 90 100 110 120 130 Fig. I . Cross-section on a north- south line of the south face of the Breithorn, showing both tunnels and the water reservoir. Isotherms, marked in degrees Fahrenheit, have been sketched in to join IJ oints of equal temperature in the two tunnels, and have been proj ected up and do wn through the neve ~ Y the author rose with minor oscillations from - 14° C. at the beginning to - 5° C. at stations 30~40 m. and then reverted to - , 3° C. at the rock interface, at its end. Having expected to find temperatures rising all the way to bedrock, I was confused, but eventually reconciled this surprise by the fact that the rock behind the tunnel was only a subsidiary rock ridge, the opposite side of which, not so many tens of meters horizontally through the rock beyond this tunnel heading, was one great face of bare rock, exposed to the very low mean annual atmo­ spheric temperature appropriate to 4,200 m., and the thermal conductivity of that solid rock, being very much higher than that of the insulating nivi (rock being relatively less insulating, see Fisher ('955, p.