The Physiography of the Proposed Federal Territory at Canberra for Approval for Publication
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ArchivesACT Research Guide -METEOROLOGY OF AUSTRALIA. COMlVION\iVEALTH BUREAU OF ~lETEOROLOGY~ ME I ... BOURNE. THE PHYSIOGRAPHY OF THE PROPOSED FEDERAL TERRITORY AT CANBERRA BY GRIFFITH TAYLOR, B.Sc., B.E., B.A., F.G.S. (PHYSIOGRAPHER, COMMONWEALTH METEOROLOGICAL BUREAU). BULLETIN No. 6 . ISSUED DECEMBER, 1910 . ., J>ublislted u;ith the Autlwrity qf the l11iniste1' qf Home A!Jair·s. H. A. HUNT, COl\IMONWEALTH METEOROLOGIST l'rintecl and Published for the GOVERNMENT of the COMMONWEALTH of AUSTRALIA by J. J\:EMP. Government Printer for the S tate of Victoria. C. l2953. ~----~-- ArchivesACT Research Guide Melbourne, 22nd August, 1910. Sm, I have the honour to submit the following paper by Mr. Taylor on the physiography of the proposed Federal Territory at Canberra for approval for publication. Mr. Taylor has treated the subject of his work in an exhaustive manner. He has correlated the topography, the vegetation, the soil, meteorology, and seismology of the districts, and has summarized and discnssed its economic aspects under the headings of- (a) Communication; (b) Vegetation; (c) Mining ; · (d) Crops; (e) Rainfall. The stereogram or relief map of the area will be invaluable in projected operations of the variour; departments in establishing the capital and its surroundings, and to the Meteorological Department, particularly so as it will enable a better appreciation of the climatic peculiarities of the areas, both as to incidence and general conditions of weather. As this Department is hampered in its functions by the lack of physiographical knowledge, it is hoped that this valuable and unique work (so far as Australia is concerned) may be the initiation of a scheme to include in detail a physiographical survey of the whole of the continent, more especially of the Eastern States and the south-western portion of Western Australia. Mr. Taylor has made some interesting notes on the Cotter River and its watershed, and, from what he has said with regard to Mounts Bimberi and Tidbinbilla, it may be concluded that, in addition to an unfailing supply of water from that river (which local experience has already established), it is not likely, from the inaccessibility of its source, to be readily polluted, and, from the elevation of that source, is probably subject to an annual average minfall equal to that of Kiandra, viz., 64 inches, or even more. as it is over 1,000 fee t higher, and is exposed to the same rain-bearing winds. I have the honour to be, Sir, Your obedient servant, H. A. HUNT, Commonwealth Meteorologist. 'l'h A Secretarv, Home- Affairs Department. ............ " ArchivesACT Research Guide CONTENTS. PAOB f. lNTRODIJC1'lON 7 II. ToPOCRAPHY- (a) Lake George Area 7 (b) The lliolonglo Valley 7 (c.) The Murrumbidgee Valley 8 (d) The Tharwa G1tp . 8 (1) "Boat-hook Bends" (2) " Crossed-fork " Contours (e) The Canberra Plains 8 (/) The Canberra Monadnocks 8 (g) Trans-Murrumbidgee Area 9 (h) Summary .. 9 III. THE EvoLUTION OF A LAND SuRFACE (a) Young Features D (b) Mature Features !) (c) Senile Features D IV. THE EvoLtrTJuN OF THE CANBERRA ToPOGRAPHY (a) Pre-uplift Features .. 10 (b) Canberra "Tilt-block" !I) (c) Rivers of S.E. Australia 11 I d) 1'he Seismic Area . _ ll A History of the Topographic Cycle ll V. SoME EcoNoMic AsPECTs- (a) Communication (roads and railways) 12 (b) Vegetation . _ . 12 (c) Mining (building stone, &c.) .. 13 (d) Soils (agriculture) .. 13 (e) Meteorology (rainfall) 13 (The Great Monaro Valley) 13 PLATES. Figure I.-Approximate Contour Map of the Territory {2,400 and 1,900 feet). H.-Profile along the 1\Iolonglo River. III.-Cross-section of Murrumbidgee Valley, and "Tilt-block." IY.-Barren Jack D[],m- a river br~tnching normally. V.-Tho 'T'harwa Gap, with approximate contours {2,000 and 2,400 feet). VI.-Somf.' of tho " Boat-hook Bends." VII.-Skekh of Junction of the Naas and Gudgenby. VIII.-" Crossed-fork Contours" at Tharwa. IX.- SkPtch of Canberra Plains. X.- Reguiarly arranged Tributaries of the Molonglo. XI.- Diagrammatic Sections of the Peneplain. XII.- Physiographic Divisions of the Territory. XIII.-Young and Mature River Valleys. XIV.- Sketch of the Murrumbidgee Scarp to the West of Strom. XV.-The Canberra "Tilt-block." XVI.-Present River Systems- showing abnormal features. XVII.-Ancient River Systems restored- XVIII.- Correlation of Seismic Regions with anomalous River Evolution XIX.-Sketch of the Molonglo Defile. XX.-Approximate Rainfall Chart of the Great Monaro Valley. X XL·-- Approximate Contour Map of the Great Monaro Valley. Figure :1 -Photograph •L'f the Relief Map o~ the Territory. · ~ ArchivesACT Research Guide ' FIG. I.-The topography of the Federal Territory (see also Fig. 12). The circle shows the position of the proposed city. The contours are only approximate. o~,,..~ • /•I N ~~~=:·• HA.LL • -. •J • over 2t,.oo' - 19oo- 24-oo' I I M!L.~S 0 s 10 under 1900 1:?::.-:.::.~.~~ FIG. 2.-Profi.:le along the Molonglo River, showing the section of the defile (hatched) and the step in the grade above Queanbeyan. S.E. ?If/" CC'IIIVO'J.!I~I'Vn..!J q~c>-t>' N .W. 'Molonglo Def'i le Queon"b'!.!jon ~ 'Molonglo .3ooo' Jl#qcf..on wit'"#, CANBERRA t /.900' ---- ~ AAEA ~/ ·.2. 40o' .-..l"'turrvmb ;dgee £O L- f: ~ I_::!..- -- A'o~ .:: ~ "-"'="-- l 1~00' I),.,-£.A0~ - 6 £. 0 0 ~ 0 o"!¢ 2.000' ~~~~~~--- - - OPt!."' " "'L4-f:"( -7-f""NA.R.AO'N • ..;O~* ::.~~; 7~ NOt{MAl UPPER. VALLEY ~ T.G. r. ArchivesACT Research Guide THE PHYSIOGRAPHY OF THE PROPOSED FEDERAL TERRITORY AT CANBERRA, BY GRIFFITH 'l1AYLOR, B.Sc., B.E. (SYD.), B.A. WAN'l,AB), F.G.S. INTROD1JCTION. Divide. But it does not reach the Murrumbidgee River In 1907 I had made a physiographic survey of the Lake system for some :!0 miles. Here we enter one of those George area.* It abuts on the Federal Territory, and is rare topographic features--an area of inland drainage. structurally a portion of the region on which the proposed In a few miles the train descends to Bungendore, and capital is to be built. By direction of the Home Secretary a little to the north lies the large bare plain which con and the Commonwealth Meteorologist, in July, 1910, I stitutes the dry bed of Lake George. If we compare the prolonged my survey to the west for a distance of 30 miles, land features on the two shores of the lake we are struck and collected data for the construction of a stereogram with their dissimilarity. In an earlier paper I have written or relief map of the area. A photograph and description as follows :- of this accompanies the report. " On the eastern shore the lake outline is somewhat I preface this brief account of the physiography o£ the irregular. Ondyong Point, Rocky Point, CilD.andooley, Federal Territory by two extracts from the first volume and Native Dog mark the spurs projecting from the Gourock issued by the Maryland Weather Service, perhaps the Range into the lake. In broad valleys between these most complete in the Tinited States, for it records the meteor spurs lie the streams which water Lake George; Murray's ology of the Federal Capital, Washington. Creek, Taylor's Creek, Deep Creek, and Turallo Creek. In this classical work, issued in 1899 by the Johns It will be noticed that these creeks converge on the locality Hopkins University, over 200 pages are devoted to a known as Geary's Gap. description of the physiography of the country around " Reverting to the western shore, we are struck by the Washington. The following paragraphs emphasize the close absolute dissimilarity. Standing at the le,rel of the lake relation of physiography and meteorology, and specifically we seem to be confronted by a great wall extending state the necessity for a physiographic survey under northwards for over 20 miles from the l\1olonglo Plain. conditions analogous to those in Australia. No broad valley breaks its continuity. Indeed, to one " The climate of a particular district is furthermore cycling along the foot of the Cnllarin Range, it seems determined by so many factors of a general and specific unbroken by any definite gap, while for ,~ large part it nature that the consideration of many topics, apparently presents a steep face 500 feet high to the lake. From more or less remote from what we commonly regard as the eastern shore, however, one is able to see a well-defined climate, must be undertaken. Thus, for example, we gap about half-way along the western shore, where the must understand the topographic and physiographic old Southern Road crossed the Cullarin Range. This features of the region if we would rightly interpret its depression- Geary's Gap--was well known in the d<1ys climate, but, in order to comprehend these features properly, before the railway, but is now practically unused by a k-nowledge of geology is necessary." travellers. Less than 2 miles south of Geary's Gap, a Again, the Director (W. B. Clarke) writes:- stream (Grove Creek) rushes down to the lake. Contrast its course ·with that of Tavlor's Creek, on the eastern shore. "It is impossible to fully comprehend our climatic The latter stream flows through a broad valley, a mile or conditions without a knowledge of the distribution of two wide, scooped out of the granite, and shows the even our land and water areas, of the location and elevation grade of a long-established river. The Grove Creek is of our mountains, and of the extent and position of our barely a mile long, yet descends nearly 300 feet. Its plains. Such investigations of the natural physiographic course is interrupted by falls 25 feet high, and finally it features of the State have a very practical significance to emerges from a gorge or miniature canyo"n with steep sides the inhabitants of Maryland, and for those who are con 200 feet high.