Glaciology program

Important components are seasonal snow , sea ice , glaciers , ice sheets and frozen ground. The extent of these types of ice reflects the present and past climate.

Examples are: hemispheric snow cover in winter, thickness of sea ice on the polar oceans, depth of frozen ground, volumes of glaciers and the physical and chemical properties in layers cored from ice sheets. The ice also affects climate.

For example, the large areas covered by snow and sea ice reflect solar radiation away from the Earth's surface and thereby influence the heat balance of the earth.

Because these ice components are only decimeters to meters thick, they can change on time scales as short as seasons and can influence climate at all time scales. Glaciers and ice sheets are hundreds to more than one thousand meters thick and change significantly only on decadal or much longer time scale. Zero depth represents snow surface of June, Table 1 shows some of the data for the South Pole station.

Unfortunately, not enough samples were collected from a single accumulation layer to determine the regularity of sea- sonal variation. On the other hand large variations i n the S values exist, and the regularity and amplitude of this variation can be tested by further samplings.

With air drops supplied by the U. The station was reoccupied i n February The main camp and observation site were located near the head of the glacier's highest cirque at an elevation of meters. The micrometeorological program, syn- optic weather observations, and the snow study program were conducted from this sta- tion.

A lower camp was established on a la t e r a l moraine of the valley tongue m about five km from the main camp and two-and-one-half km up-glacier from the terminus. Surface motion studies and ablation measurements were carried out during the summer from this camp.

Surface Motion Studies The ice motion surveys on the McCall Glacier were established i n order to find the character of movement m the surface ice and to help i n the determination of the mass budget. Standard triangulation methods were used to determine the magnitude of the ice motion.

Four lat e r a l profiles of nine stakes each and a set of five stakes i n the ter- minus were positioned i n May and June and surveyed from that time through October. An independent baseline at each p r o f i l e was set up to take stereo photos and accomplish the survey. The length of each base was chosen to be the photogrammetric optimum with respect to the length of the p r o f i l e.

This ra t i o meant that most of the bases were on the order of forty meters, a length which also allowed the majority of stakes to f a l l within the l i m i t i n g ratios of and The baseline for one set was an exception to t h i s , i t s size being determined by the snow cover at the time of the i n - i t i a l survey with the result that a ten-meter base was used.

Once the snow l e f t i t was thought better to maintain continuity of photography so no change was made. Some d i f f i c u l t y was encountered i n establishing the bases because of the lack of stable rock to use for stations. The major portion of the valley i s either coarse moraine or the rubble-stream flanks of the ridges. I n both cases the bedrock i s too well covered to use for stations and such outcrops as do occur are not found i n l i k e l y spots for control points.

The stations were therefore marked on large boulders of the l a t e r a l moraine as i t was f e l t that creep would not be too great here. The surveys were made with the theodolite incorporated m a Wild T Phototheodolite. I t was observed early i n the summer that varying weather conditions could af- fect the reading of an angle by as much as ten sexagecimal seconds.

Refraction of A l l angles were read twice d i r e c t and twice reverse to a tolerance of ten seconds. While t h i s increases the oppor- t u n i t y f o r mechanical e r r o r s , l i k e misreading an angle, the progress had been slowed to such a degree by heavy p r. The use of greater care appears to have obviated any such gross e r r o r s , however, and the surveys were accomplished more r a p i d l y. P r e - f i e l d planning had not envisaged the magnitude of the melting on the lower portions of the g l a c i e r.

Consequently, a few stakes near the terminus f e l l out and t h e i r p o s i t i o n and motion l o s t f o r that period. Detailed studies on the a b l a t i o n of the lower McCall Glacier were c a r r i e d out from June 23 to September 1, A b l a t i o n and accu- mulation on the lower McCall Glacier was determined by measuring changes i n surface l e v e l , and, i n the case of snow, changes i n density.

McCall Glacier ice i s here as- sumed to have a density of 0. At the intermediate camp two wooden dowels, 2. Measurements of height of stake above the surface, depth of snow, and density of snow were made d a i l y.

Both stakes were p e r i o d i c a l l y reset as surface lowering exceeded by several times the depth of the stakes i n the i c e. Height of stake above the snow and depth of snow were measured at the movement p r o f i l e stakes each time the p r o f i l e s were surveyed or roughly once every three weeks. The stakes used f o r movement studies were i d e n t i c a l to those at the intermediate camp.

Some stake records at the p r o f i l e s were discarded as the stakes had melted out com- p l e t e l y between observations. The number of stakes at each p r o f i l e insured complete coverage of a l l conditions of slope and snow depth on the lower g l a c i e r.

The formation of super- imposed ice was determined by probing. The depth to the f i r s t hard surface encountered was subtracted from the known depth of the o r i g i n a l surface to give the thickness of the superimposed i c e. Snow depth and density of snow i s required to compute the depth to the o r i g i n a l surface. Not a l l i n d i v i d u a l stake measurements covered the same time spans; ther e f o r e , to determine t o t a l summer loss i t was necessary to set up a r a t i o of the loss at any one stake to the loss over the same period at the intermediate camp stakes.

I n order to do t h i s i t must be assumed that rates of a b l a t i o n at the p r o f i l e stakes were constantly i n the same propo r t i o n to those at the intermediate camp stakes. Data and reports have been submitted to World Data Center-A. The period June 23 to September 1, was estimated to be roughly co- incident w i t h the summer a b l a t i o n season f o r that year. The lower McCall Glacier was snow-free throughout most o f the summer, thus surface lowering was due to the melting of g l a c i e r i c e.

As no g l a c i e r i n the Brooks Range had been studied previous to t h i s p r o j e c t , and as few meteorological records were a v a i l a b l e , there had been no way to p r e d i c t the rate of melt which might be expected. A b l a t i o n values were s u r p r i s i n g l y high, i n f a c t , not a great deal less than those recorded on the Blue Glacier, Olympic Mountains, Washington, which i s very d e f i n i t e l y a temperate g l a c i e r. The stake which served as a reference point f o r surface change measurements was located on the crest of the g l a c i e r near the intermediate camp.

Daily measurements were also car- r i e d out at another stake 70 m away on the edge of the g l a c i e r where the slope was o at r i g h t angles to the general trend of the g l a c i e r. Surface lowering was only a few m i l l i m e t e r s higher per day at t h i s stake.

Snow Cover. The snow cover present on June 23 was the r e s u l t of l a t e May and ea r l y June storms. The snow cover i n July and August was present only a f t e r a storm and then disappeared very r a p i d l y. These were avalanche d r i f t s located along the west w a l l of the g l a c i e r.

I t may be said that without doubt the metamorphism of snow i n t o f i r n does not c o n s t i t u t e a means of acciunulation of the lower g l a c i e r. I t seems possible that the lower g l a c i e r i s nearly snow-free throughout most of the winter due to high winds and l i t t l e p r e c i p i t a t i o n. This was observed to be the case during l a t e October, b. Superimposed Ice. Superimposed ice was observed to form a f t e r storms under a snow cover and was followed by melting of the snow.

Melt water p e r c o l a t i n g through the snow cover probably freezes on contact w i t h the g l a c i e r ice surface which i s kept cool through the i n s u l a t i o n provided by the snow cover. Very l i t t l e ice forms during the summer because of the r e l a t i v e l y warm temperature of the surface i c e.

The observed s t r a t i g r a p h y was as follows: 4 cm of new snow w i t h small i n - d i v i d u a l star-shaped c r y s t a l s 2 mm i n diameter, cm of greyish porous ice which flaked away from the lower ice surface when struck. Below t h i s layer was a white dense i c e. The porous i c e i s believed to be superimposed i c e. I t was t h i c k e s t i n the micro- r e l i e f v a l l e y s where there would have been the greatest accumulation of water. This ice was undoubtedly formed at the very end of the a b l a t i o n season.

Several times during the summer when the nighttime a i r temperatures had dropped below freezing a s i m i l a r formation was noted on the g l a c i e r.

I t was very smooth i n contrast to the normally rough surfaoe and impaired walking. Superimposed i c e forms i n large quan- t i t i e s only i n two places on the g l a c i e r where small lakes e x i s t during the summer. As both lakes are i n areas where there i s snow throughout the summer, they are prob- ably preserved from year to year w i t h each summer's lake forming on top of the previous summers.

Meteorological Data. The synoptic observations f o r the complete period of oc- cupation have been tabulated, and published see b i b l i o g r a p h y. I n a d d i t i o n , a l l micrometeorological data have been successfully reduced from the o r i g i n a l recorder data to meteorological values by the use of e l e c t r o n i c computer and machine t a b u l a t i o n s , The p a r t i c u l a r items were measurements of solar r a d i a t i o n , albedo of snow and ice surface at regular i n t e r v a l s throughout the year, measurements of wind gradients above the ice surface, study of a b l a t i o n and accumulation of the snow and ice at the surface, v a r i a t i o n s i n pack ice thickness, measurements of temperatures above and i n the pack i c e , and the study of age of the ice at d i f f e r e n t depths by s t r a t i g r a p h i c means and by c r y s t a l o r i e n t a t i o n studies.

The remainder of the support came from p r o j e c t 9. G l a c i a l geology i s a branch of geomorphology dealing w i t h the c o n f i g u r a t i o n of the surface, and the changes i n land forms that have taken place i n areas once covered w i t h g l a c i e r i c e. See also unnumbered p r o j e c t B, at end of t h i s chapter, f o r other geological work supported under 4.

A small group operated out of McMurdo Sound, concentrating t h e i r e f - f o r t s at Marble Point, October through January The studies at Marble Point included: a. Caliche formation i n the active zone g. I n a preliminary report on the i n v e s t i g a t i o n s at McMurdo Sound, the i n - v e s t i g a t o r reported on several aspects of coastal geomorphology at McMurdo Sound.

The highest measured elevated beach on Dunlop I s l a n d was The marine l i m i t at Marble Point i s The marine l i m i t therefore does not t i l t between these two po i n t s. A radiocarbon measurement of an elephant seal, buried i n an elevated beach about Some elevated beaches terminate more or less perpendicularly against the Wilson Piedmont Glacier. An extensive elevated beach found at Marble.

Point i s between The beach gravels are i n places only 38 to 51 cm t h i c k , and they r e s t on clean ice which, m one place, i s more than 2. Numerous round, oblong, and i r r e g u l a r l y shaped p i t s and hollows are found on many of the beaches. They range m diameter from less than 4. During the f u l l - b o d i e d stage of g l a c i a t i o n , the Wilson Piedmont Glacier terminated m deep water. The f i r s t beaches were formed at the terminus of the g l a c i e r , and younger and younger beaches were formed at increasing distances from i t.

Several features i n d i c a t e that the f i r s t beaches were formed close to the g l a c i e r. The highest beaches i n many places are p i t t e d. P i t s are not found i n general on the lower beaches. This suggests that the p i t s were formed by the melting of fragments of ice which f e l l from the g l a c i e r onto the beaches and were buried by beach gravels.

A gap approximately 30 m long i s found i n the highest beach ridge near Marble Point. I t seems l i k e l y that the gap r e - sulted from the erosional a c t i v i t y of a meltwater stream which came from the g l a c i e r when I t was close to the beach. The highest beach i n the southern part of the main- land near Spike Cape i s abruptly truncated on the south.

The presence of the Wilson Piedmont Glacier i n the area where the highest beach i s not now found when t h i s beach was being formed elsewhere, followed by g l a c i a l r e t r e a t i s responsible f o r the t r u n - c a t i o n. The absence of the highest beach ridge on a kame ridge near the mouth of the "Surko River" indicates the presence of ice i n t h i s area when the highest beach was being formed elsewhere.

The presence of p i t s on some of the highest beach ridges, of a meter or so of ice beneath beaches m above sea l e v e l , of a buried elephant seal i n an elevated beach Science i n press This special p r o j e c t sub-project of 4. The i n t e n t i o n was to observe s t r u c t u r a l features of the ice and measure the stresses and s t r a i n s as a model, on a much accelerated time scale, of processes i n the earth's rock c r u s t.

Geologists, i n t h e i r attempts to i n v e s t i g a t e the mechanism of rock defoinnation, have been hampered by the lack of a s u i t a b l e m a t e r i a l from which t o make a proper scale model; many well-known experiments are i n the l i t e r a t u r e but have not produced a usable analogy to rocks under n a t u r a l conditions.

Glacier i ce i s a monominerallic c r y s t a l l i n e rock. I t o r i g i n a t e s through meta- morphism of f i r n , a granular sedimentary rock formed by diagenetic processes i n the perennial snow cover of regions favorable t o net annual snow accumulation.

Analysis of the two-dimensional stress p a t t e r n and s t r a i n rates has led to the formulation of a flow law f o r i c e. The Ice Shelf Deformation Pro- j e c t was not proposed as a means of e s t a b l i s h i n g new physical constants f o r i c e , but rather f o r the purpose of observing and recording the behavior of a f l o a t i n g i c e sheet as a n a t u r a l scale-model experiment.

One of the greatest values i n using the Ross Ice Shelf as a t e c t o n i c model l i e s i n the short time involved i n the production of f o l d s and other s t r u c t u r a l features. I n other rocks these g e o l o g i c a l s t r u c t u r e s require enormous time spans f o r develop- ment, whereas on the Ross Ice Shelf a n t i c l i n e s and synclines w i t h amplitudes of 10 meters and wave lengths of about meters develop i n a decade or so.

Such a short time-span permits the geologist to observe the process of f o l d i n g while i t i s a c t u a l l y i n operation. The value of the scale-model approach, and the p r i n c i p l e of u n i f o r m i t y of n a t u r a l phenomena are accepted by geologists; the Bay of Whales area provides an excellent place to acquire a considerable amount of knowledge about very elusive yet important geologic processes see Figures 6 and 7.

For the f i r s t time i t has been possible to determine the s t r a i n f i e l d which ac- companies the formation of f o l d s. Further advances may also be made i n the under- standing of such s t r u c t u r a l processes as j o i n t i n g.

Over most of i t s , sq. The Ross Ice Shelf has been known to contain s t r u c t u r a l features s i m i l a r to those i n layered rocks since the days of the Byrd Expeditions. Inasmuch as a n t i c l i n e s , synclines, shear zones, and f r a c t u r e s crevasses e x i s t there, the s u i t a b i l i t y of using the p o r t i o n of the Ross Ice Shelf i n which these features occur as a model f o r studying the processes of rock deformation was recognized by Bucher.

The f i e l d program of the Ice Shelf Deformation Project was i n i t i a t e d i n September, , The general mapping program was g r e a t l y enhanced and accelerated by the use of a e r i a l photographs taken from an a l t i t u d e of 5, feet w i t h a 6-inch camera i n January, Temperature measurements were made d a i l y at various depths, and accumulation stakes were set out i n s t r a t e g i c areas.

The camp was evacuated on January 7, , and l e f t unoccu- pied during the a n t a r c t i c w i n t e r. Camp Michigan was reoccupied by a second f i e l d p a rty i n November , f o r the purpose of continuing the deformation studies. The main e f f o r t s of the second team were centered around the determination of s t r a i n rates i n selected areas, f u r t h e r s t r a t i g r a p h i c studies, and p e t r o f a b r i c analyses of deformed ice layers.

Two deep cores, 3 inches i n diameter, were hand-augered and transported to the U n i v e r s i t y of Michigan, where they were studied i n d e t a i l. P a r a l l e l Crevasse Systems. The crevasses generally trend i n an east-west d i - r e c t i o n , and range i n w i d t h from less than a h a l f meter to more than 8 meters.

Some crevasses extend f o r a distance of 1 km but many are less than h a l f t h i s distance, and most of the crevasses are a few hundred meters long.

The depths of the few cre- vasses measured ranged from 19 to 25 meters. However, most of these soundings do not r e f l e c t the r e a l depths, since most of the crevasses contained collapsed snow bridges at the bottom. The a n t i c l i n e s are more pronounced, topographically, than the synclines, because the l a t t e r are traps f o r d r i f t i n g snow and, therefore, tend to be subdued i n surface expression as soon as they are formed.

The f o l d s have amplitudes of 5 to 15 meters w i t h wave lengths of meters or more. The s i m i l a r i t y of these s t r u c t u r a l features of the Ross Ice Shelf to folded sedimen- t a r y rocks i s immediately apparent. Furthermore, the f a c t t h a t the axes o f most, but not a l l , of the fol d s are orthogonal to the crevasse systems i s s t i l l another argument i n favor of a systematic stress p a t t e r n i n the area. Seismic soundings i n the deformation area were made by Cook and Crary on separate occasions.

Cook reports meters of ice shelf at t h i s p o i n t , and Crary reports meters. At a p o i n t on the baseline meters toward B from A F i g. Depth of Water.

Cook reports a depth of meters at s t a t i o n A Camp Michigan , and Crary reports meters f o r the same place. Nowhere i n the e n t i r e deformation area i s the i c e grounded.

The strong deformation i n the Camp Michigan area i s therefore not produced by any drag or f r i c t i o n on the bottom, but r a t h e r by a h o r i z o n t a l stress system i n the shelf r e s u l t i n g from northward flow around the east and west sides of Roosevelt I s l a n d. Unfortunately, no r e l i a b l e t h i c k - ness measurements were obtained at an a n t i c l i n a l crest and at the trough of an adja- cent syncline. I t i s , t h e r e f o r e , not possible to state whether the ice thickens as i t f o l d s , although from t h e o r e t i c a l considerations alone, i t would seem th a t the ice shelf thickness measured v e r t i c a l l y through the crest of an a n t i c l i n e should be greater than the i c e thickness measured through the trough of an adjacent syncline.

Density determinations were made i n the w a l l s of snow p i t s , crevasse w a l l s , and hand-augered cores. Density determinations at the a n t i c l i n a l crest and ad- jacent s y n c l i n a l trough near s t a t i o n D show a markedly higher density at corresponding depths when compared to those from crevasse Alpha. The increased density i n the folded ice may be the n a t u r a l consequence of the compressional h o r i z o n t a l stresses which pro- duced the f o l d i n g.

Some of the p l a s t i c deformation induced by the h o r i z o n t a l stress i s apparently taken up i n the Increased density of the f l r n. Another f a c t o r t h a t undoubtedly accounts f o r some of the i n - crease i n density of the folded f i r n i s compaction by wind on the crest of the a n t i - c l i n e.

Density values i n the upper meter of the a n t i c l i n a l crest are generally higher than the upper meter of the adjacent trough. But, the f a c t that the density values f o r both crest and trough are generally higher than those at comparable depths i n non- folded areas argues i n favor of the increased d e n s i f I c a t i o n by l a t e r a l compression.

J i m Stratigraphy. Giovinetto's snow p i t studies i n d i c a t e the average net an- nuat aceumulation f o r the non-disturbed area i n the v i c i n i t y of Camp Michigan to be The basis f o r t h i s conclusion i s r e l a t e d to the f a c t t h a t , i n , the crest of the a n t i c l i n e i n question r e - ceived less accumulation than the trough of the adjacent syncline, but that sometime i n the past, before the crest stood s i g n i f i c a n t l y higher than the surrounding snow surface, there was no s i g n i f i c a n t d i f f e r e n c e i n the accumulation between crest and S t r a t i g r a p h i c studies show that the year marked the beginning of a trend i n which the crest received less accumulation because of i t s increased height above the surrounding surface.

Kehle's data on s t r a i n rates involve base l i n e measurements and a t r i a n g u l a t i o n network of the gross deformation area, rectangular g r i d systems of stakes placed m selected locations which contained deformation features such as crevasses or fo l d s i n varying degrees of development; surface s t r a i n r o s e t t e s ; peg rosettes on crevasse w a l l s ; and d i r e c t measurement of the ra t e of crevasse opening.

I n general, Kehle shows th a t f o l d axes are almost always perpendicular to the p r i n c i - pal compressive axis, but tha t crevasses are e s s e n t i a l l y perpendicular to the p r i n c i - pal tension axis except i n the immediate v i c i n i t y of the a n t i c l i n a l c r e s t s where the crevasses make a considerable angle w i t h respect to the p r i n c i p a l axes of stress.

I n an independent evaluation of the age of the major study a n t i c l i n e , Kehle a r r i v e s at a f i g u r e of years based on rough measurement of a n t i c l i n a l growth. Petrofabrics of a Folded Ice Layer. The maximum concentration of the c-axes i s 8 to Congress, XXL Session. Meeting, Geolog. America, v. John R. Meeting Geolog. Zumberge, M. Kehle, J. Ralph 0. America B u l l. Vivi U. The f i e l d work of t h i s p r o j e c t was accomplished i n December through February , based from McMurdo Sound, A n t a r c t i c a.

Navy h e l i c o p t e r f a c i l i t i e s made possible the establishment and re-supply of camps i n Taylor Dry Valley and other g l a c i e r free locations on the east, west and south sides of McMurdo Sound.

The geol o g i c a l party camped out i n the area and examined the many geological features. Navy a e r i a l photography of the region was obtained as a d d i t i o n a l information. Many samples of unconsolidated sediments were taken as w e l l as many bedrock samples f o r examination m laboratory and o f f i c e a f t e r r e t u r n i n g to the United States.

The o u t l e t g l a c i e r s emanate from the ice cap and d r a i n through passes toward the sea, the small alpine g l a c i e r s o r i g i n a t e i n the mountains and are independent of the ice cap. The g l a c i e r s are polar g l a c i e r s and no water issues from underneath or w i t h i n them; however, during December and January, some meltwater runs from the sur- face of the lower ends of the g l a c i e r s , forming t r a n s i e n t shallow streams.

Some of these streams extend to the sea but most of them d r a i n i n t o landlocked lakes. The climate of the McMurdo Sound region i s rigorous, character- ized by low temperatures mostly below f r e e z i n g , a r i d i t y annual r a i n f a l l inches , and wind. At least four Quaternary g l a c i a t i o n s a g l a c i a l ad- vance and r e t r e a t represented by deposits and landforms t h a t can be distinguished from other g l a c i a l deposits of d i f f e r e n t ages are recorded i n.

The youngest advance l e f t d r i f t t hat i s s t i l l cored w i t h g l a c i a l i c e ; the two next older advances are marked by subdued moraines; deposits of the o l d - est recognized g l a c i a t i o n , however, are scanty and only preserved on high ridges.

Sketch map by T. Base modified a f t e r U. Navy Hydro- graphic O f f i c e Chart No. Patches of d r i f t of t h i s g l a c i a t i o n occur on,ridges 2, feet above sea l e v e l on the west side of K o e t t l i t z Glacier, and m Taylor Dry Valley about 3, feet above sea l e v e l , 2, feet above the f l o o r of the v a l l e y , near the top of Mount Nussbaum.

Great a n t i q u i t y of the McMurdo G l a c i a t i o n deposits i s ind i c a t e d by the lack of morainal form and the boulders and cobbles planed l e v e l w i t h the ground surface by wind abrasion. During McMurdo G l a c i a t i o n , Taylor Glacier, dr a i n i n g the expanded ice cap, f i l l e d Taylor Dry Valley to an e l e v a t i o n probably higher than 3, feet and co- alesced w i t h the expanded K o e t t l i t z Glacier i n McMurdo Sound, as d i d the Ferrar Gla- c i e r.

I t also coalesced w i t h the Ross Ice Shelf and i t i s conjectured, by p r o j e c t i n g o l d ice-surface p r o f i l e s , that the ice completely cov- ered Brown I s l a n d , 2, fe e t high, and Black I s l a n d , 3, feet high.

Also, i f Mount Discovery probably i n part a Pleistocene volcanic cone were near i t s present height, the i c e surrounded the mountain up to an e l e v a t i o n of approximately 5, f e e t. The ice of the McMurdo g l a c i a t i o n must have extended to 2, feet above sea l e v e l on the flanks of ancestral Mount Erebus.

The Taylor Glacier f i l l e d Taylor Dry Valley w i t h ice to an el e - v a t i o n of approximately 1, feet above sea l e v e l. Ferrar Glacier pushed out i n t o the Sound as the ice cap expanded. Strong ice push from the K o e t t l i t z Glacier to the south e v i d e n t l y caused the Ferrar Glacier to wrap around the base of the Kukri H i l l s , merge w i t h Tay- l o r Glacier, and push up t o 1, to 1, feet above sea l e v e l around H j o r t h H i l l and Hogback H i l l.

This ice coalesced w i t h the Wilson Piedmont Glacier. Also, g u l l i e s and canyons have been cut through the d r i f t by small streams that e x i s t only a few days a year. A series of raised marine beaches, the highest about 66 feet above sea l e v e l , occur i n f r o n t of Wilson Piedmont Glacier. They formed since the Wilson Pied- mont Glacier withdrew from the area at the close of the F r y x e l l G l a c i a t i o n.

This phenomenon may also be used as a crude measure of the age of the F r y x e l l G l a c i a t i o n because i t must have taken considerable time f o r u p l i f t , and formation of the beaches i n a Sound which was frozen most of the year. Navy Hydrographic O f f i c e Chart No.

The o u t l e t g l a c i e r s and shelf ice were much more extensive. The i c e almost covered Brown I s l a n d as i t pushed up to 1, feet above sea l e v e l , and covered the western part of Black I s l a n d up to a height of at least 1, The age o f the K o e t t l i t z G l a c i a t i o n i s not known but considerable time must have elapsed to b u i l d large deltas i n the ice-dammed lakes that existed during t h i s g l a c i a t i o n , because streams i n the area are small and extremely ephemeral, flowing only a few weeks a year.

K e t t l e lakes i n the ice-cored moraine contain algae. I n May the status of g l a c i a l chronology of New Zealand w i t h a possible c o r r e l a t i o n to North America was published by Gage and Suggate. The sequence suggested f o r the McMurdo Sound area may represent most of the Pleistocene epoch, or i t may be equivalent to only the Wisconsin stage of the North American chronology.

G l a c i a l moraines sometimes have a core of stagnant g l a c i e r ice protected by a debris cover 30 to cm t h i c k. The McMurdo Sound region of A n t a r c t i c a contains the largest known area of ice-cored moraines. The most extensive area of these moraines i n the region i s that derived from the advance of K o e t t l i t z Glacier during the l a t e s t major g l a c i a t i o n.

The ice-cored moraines of the McMurdo Sound region g r e a t l y resemble the young ice-cored moraines of temperate l a t i t u d e s. The surfaces of the ice-cored moraines of K o e t t l i t z Glacier are characterized by s h i f t i n g knob and k e t t l e topography, ephemeral lakes, algae and m i r a b i l i t e deposits, and a polygonal m i c r o r e l i e f p a t t e r n.

Ice-cored moraines i n temperate l a t i t u d e s are generally regarded as only to years o l d , however, because of the extremely cold, a n d climate, the ice-cored moraines of McMurdo Sound are believed to be much older.

The presence of sand wedge polygons provides a d d i t i o n a l evidence f o r the a n t i q u i t y of these moraines.

Radiocarbon dating of algae incorporated i n the a b l a t i o n d r i f t morainal debris give a minimum age of 6, years f o r the ice-cored moraines adjacent to K o e t t l i t z Glacier.

Radiocarbon dating of mummified seal carcasses l y i n g near g l a c i e r f r o n t s i n d i c a t e that the g l a c i e r s have not been more extensive f o r at least years. The youngest mo- raines m the area are ice-cored moraines to the e x i s t i n g g l a c i e r s. Radiocarbon dates of algae from e x t i n c t ephemeral ponds i n the ice-cored moraines i n d i c a t e the moraines to be at least 6, years o l d. A d d i t i o n a l evidence f o r the a n t i q u i t y of the near-glacier moraines i s indicated by the presence of a rather uniformly w e l l developed m i c r o r e l i e f p a t t e r n of sand-wedge polygons on both the end moraines and the ground moraines extending up to the e x i s t i n g g l a c i e r f r o n t.

Studies i n d i c a t e that i t requires hundreds i f not thousands of years fo r such w e l l developed polygonal patterns to form. The term "sand-wedge" polygon i s here proposed f o r t h i s widespread phenomenon. The sediments adjacent to the wedge have been deformed upward and may be v e r t i c a l or overturned near the top of the wedge.

The upwarping decreases downward. Periodic c o n t r a c t i o n cracks i n the per e n n i a l l y frozen ground around McMurdo Sound, cracks produced by the great change i n temperature from summer to w i n t e r , are gradually f i l l e d w i t h clean sand which f i l - t e r s down from above i n the spring and summer.

Repeated cracking and f i l l i n g w i t h sand produces a wedge-shaped f i l l i n g. Perhaps not a l l sand wedges reported i n temperate l a t i t u d e s are replacements of i c e wedges as generally believed, but may be o r i g i n a l s t r u c t u r e s formed under an a r i d climate s i m i l a r to that which e x i s t s at McMurdo Sound today. Glaciers on the west side of McMurdo Sound th a t were photographed i n by G r i f f i t h Tay- l o r on Scott's l a s t expedition, were v i s i t e d i n under the auspices of USNC-IGY to determine g l a c i e r f l u c t u a t i o n s during t h i s i n t e r v a l.

Most of the steep-fronted, almost debris-free alpine g l a c i e r s terminate on i c e - f r e e land i n t h i s area. Termini of the Canada, Lacroix, Suess, and other g l a c i e r s were rephotographed from the same spot at which e a r l i e r photographs were taken. Mummified carcasses of the "crabeater" seal Lobodon carcinophagus l i e scattered over the land surface 1 to 30 miles from the sea and up to 3, feet above sea l e v e l m the i c e - f r e e areas.

Ninety mummified seal carcasses were noted during the f i e l d season. No doubt many others e x i s t i n the McMurdo Sound region, and probably I n other parts of A n t a r c t i c a. The occurrence of these carcasses on the surface of the ground so f a r from t h e i r n a t u r a l h a b i t a t raises the questions of why they are there, how long they have been there, and how they got there.

Two carcasses have been shipped to the United States f o r anatomical and h i s t o l o g i c a l study. This summary represents a preliminary report of our obser- v a t i o n s. A l l except one of the i d e n t i f i a b l e carcasses are of the crabeater seal.

One i s a leopard seal Hydruga Leptonyx. A f a i r l y well-preserved carcass of an Adelie penguin was found l y i n g on the ground 15 miles from the sea near seal carcasses on the west side of the Sound. The leathery dry carcasses are i n various states of pre- servation; some are r e l a t i v e l y well-preserved, and others are merely o l d , tw i s t e d , wind-dissected fragments of ti s s u e. They are dry and hard, and they have h a i r only on the side i n contact w i t h the ground; t h i s side i s generally f l a t and has a strong smell.

Twenty-five percent of the remains were found w i t h i n a mile of the sea, but scattered groups of 2 to 19 specimens were found as much The carcasses i n each group were spaced 10 to feet apart.

Most of the carcasses were found i n the v a l l e y bottoms, many along courses of ephemeral streams. Several seal car- casses were found along the edges of these lakes.

Many were found at the heads of ephermal streams where the streams issue from g l a c i e r s , or at the heads of stream v a l - leys. A l l the carcasses noted were on land except one which was found h a l f embedded i n the ice cover of Lake Bonney at the upper end of Taylor Dry Valley. A l l of those on the land l i e on top of the ground and most have 2 to 4 inches of coarse, windblown sand banked against t h e i r windward sides. The age of the mummified seal carcasses i n the i c e - f r e e land of the McMurdo Sound region i s i n t r i g u i n g.

The remains have been thought to be perhaps years or so o l d , because the a r i d and cold climate of the area i s i d e a l f o r r e t a r d i n g organic decay.

Radiocarbon analysis of one carcass showed that i t i s between and years o l d , another i s being analyzed. The m a t e r i a l , which was dated at the Lamont Geological Observatory, Columbia U n i v e r s i t y sample LB , was from a brown, weathered fragment 1 foot wide and 4 feet long. Olson and W. Broecker of Lamont Geological Observatory report as follows: "Since the radiocarbon age of any organic sample requires a knowledge of i n i t i a l r a - diocarbon concentration i t i s customary to assume t h i s to be the same as i n a s i m i l a r contemporary sample.

A lower age l i m i t involves the assumption that the seal's d i e t consisted e n t i r e l y of marine organisms d e r i v i n g t h e i r carbon from sur- face water adjacent to A n t a r c t i c a. The cold, a n d climate preserves t h e i r carcasses an i n c r e d i b l e length of time, and the remains of seals and other animals that have wandered inla n d during the l a s t years probably s t i l l ex- i s t to a t t e s t the animals' l a s t journey.

July , , Abisko, Sweden. Part V I , , pp. Rivard and G. Research Foundation, , 27 pp. Ninth Alaskan Science Conference, I, pp. Tenth Alaskan Science Conference, , pp. XXI Sessions. XXI Session. Pt, IV, , pp. Ninth Alaskan Science Conference, , pp. Series No.

Soc, , pp. Hydrology, lUGG pub. Americana, v. Rivard and T. Paper No. I n Press. Continuous records f o r the solarimeters were obtained from February 18, to February 3, One solarimeter was mounted facing upwards, the other facing down- wards, thus g i v i n g the g l o b a l r a d i a t i o n on a h o r i z o n t a l surface and the albedo.

The net-radiometer operated without i n t e r r u p t i o n from March 14, to February 3, The instruments were i n s t a l l e d on a wooden frame, about one meter apart and about two meters above the snow surface, i n an almost i d e a l l y uniform l e v e l surrounding, meters to the NE from the camp. Even at t h i s distance a small amount of contamination and disturbance by camp smoke, soot, or fog was observed. The curriculum provides a global perspective with emphasis on the Himalayan and the Alps regions.

Each module comprises of the following four sections: summary, presentations, exercises and references. The modules are being provided for academic purposes and in case the material is being used, we would request to appropriately acknowledge the contributors.