Floodplain Gravel Research Articles

Hyporheic Communities of Two Montana Rivers

Collections of stream organisms from a domestic water supply system adjacent to the Tobacco River revealed that a detritus-based community exists in subterranean waters circulating through floodplain gravels at least 4.2 meters below and 50 meters laterally from the river channel. Several stone fly species spend their entire nymphal life cycles in underground habitats of the Flathead and Tobacco rivers.

The Excavation of a Neolithic Round Barrow at Pitnacree, Perthshire, Scotland

In the thirty-mile stretch of the valley of the Tay, between its exit from Loch Tay and its entry into the more low-lying regions near Dunkeld, is a remarkable concentration of prehistoric monuments (fig. 1) which can be matched in Scotland only in the Crinan district of Argyll. The majority of sites lie on the flood plain and alluvial gravels of the valley floor, and comprise a series of standing stones, stone circles and round barrows. Until recently, little field work or excavation had been carried out on these sites, although all appeared to be characteristic of monuments of the second millennium B.C. The barrows in particular were of interest in that they appear superficially to be of earthen construction and form a distinctive group of monuments largely confined to this area. Although several had been disturbed, none had been excavated. The majority of them are tree-covered, or had originally supported trees, and many are of very great size, up to 130 feet in diameter and 30 feet in height. In an attempt to ascertain the date and cultural affinities of this group, it was decided to excavate one of these sites in 1964. The site selected was at Pitnacree, five miles east of Aberfeldy (Nat. Grid Reference NN928533). Although the barrow was covered by trees, their arrangement made it possible to excavate a considerable portion of the site, and the comparatively small size of the mound allowed a fairly full excavation. During the six-week season of excavation, a survey of analogous barrows, standing stones and stone circles in Strathtay was carried out. Details of these sites will be found in Appendix I.

Notes on the gravels of the Upper Thames Flood Plain between Lechlade and Dorchester

The paper deals with gravels which occur near the present level of the Upper Thames, and below it in terms of selected illustrative examples, mainly of recent discovery. It covers about fifty miles of the river, from the headwaters around Cricklade, where the origin of some pebbles is discussed, to Goring gap, where it is shown that a knick-point in the present river accentuates the relative height of old marginal gravels which lie upstream. The deposits of the Summertown-Radley Terrace around Oxford consist of a lower part, with a fauna characterised by woolly rhinoceros and associated fauna, and an unconformable upper part yielding hippopotamus and associated mammalian and molluscan faunas: Acheulian implements occur. The Flood Plain gravels are now known to contain remains of Siberian mammoth and reindeer, with recently discovered contemporary molluscan fauna and flora, which are described in an Appendix. No human industry has yet been attributed to the Flood Plain gravels. Means of distinguishing between the older Summertown-Radley gravels and the younger Flood Plain deposits, in the field, are explained, and it is shown that low-lying extensions and gravel-filled channels of the former occur locally beneath the latter (as at Lechlade and Dorchester).

Origin and Development of the Three Forks Basin, Montana

Research Article| July 01, 1961 Origin and Development of the Three Forks Basin, Montana G. D ROBINSON G. D ROBINSON U. S. Geological Survey, Geologic Division, Federal Center, Denver, Colo Search for other works by this author on: GSW Google Scholar Author and Article Information G. D ROBINSON U. S. Geological Survey, Geologic Division, Federal Center, Denver, Colo Publisher: Geological Society of America Received: 13 Jan 1960 First Online: 02 Mar 2017 Online ISSN: 1943-2674 Print ISSN: 0016-7606 Copyright © 1961, The Geological Society of America, Inc. Copyright is not claimed on any material prepared by U.S. government employees within the scope of their employment. GSA Bulletin (1961) 72 (7): 1003–1013. https://doi.org/10.1130/0016-7606(1961)72[1003:OADOTT]2.0.CO;2 Article history Received: 13 Jan 1960 First Online: 02 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation G. D ROBINSON; Origin and Development of the Three Forks Basin, Montana. GSA Bulletin 1961;; 72 (7): 1003–1013. doi: https://doi.org/10.1130/0016-7606(1961)72[1003:OADOTT]2.0.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGSA Bulletin Search Advanced Search Abstract The Three Forks Basin sprawls where the intricately deformed sedimentary and volcanic rocks of the Disturbed Belt along the Rocky Mountain front are faulted against the Precambrian metamorphic rocks that make the core of the Tobacco Root, Madison, Gallatin, and Beartooth ranges. Its eastern edge is linear, controlled by steep faults at the west front of the Bridger Range. All other boundaries are sinuous and show little sign of structural control.Tertiary deposits in the basin, rich in contemporaneous rhyolitic and latitic ash, are about equally of lake, bolson, and stream origin. The western part of the basin is dominated by moderately folded Eocene and lower Oligocene rocks, more than 2000 feet thick. They dip eastward beneath apparently unfolded upper Miocene and Pliocene rocks, more than 1300 feet thick, that also dip gently eastward to the basin edge.Thin but extensive Quaternary deposits lying unconformably on the Tertiary and pre-Tertiary rocks are mainly of rounded terrace and flood-plain gravel, angular fan gravel, and wind-blown silt.The basin began as part of an east-flowing stream system that developed in Late Cretaceous and Paleocene time, concurrently with Laramide folding and thrusting; the faulted contact between metamorphic and sedimentary rocks was especially erodible and became a main drainage way. Recurrent uplift to the west throughout the Tertiary provided gradient and load to the streams; additional load was provided by showers of ash from unknown vents. Relative uplifts of the Bridger Range in Eocene and early Oligocene time, and again in late Miocene and Pliocene time, impeded flow from the basin and led to deposits in channels, flood plains, and lakes. During most of Oligocene and Miocene time, however, the basin was being eroded. By the end of the Tertiary the basin was deeply filled and became part of a regional surface of low relief. Regional northwestward tilting stimulated headward erosion of the Missouri River which then captured the formerly east-draining or closed basin. The Tertiary deposits have been deeply eroded, and the rugged pre-basin surface partly exhumed. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.

On collophane in Thames gravel

In mid-1949 the London Natural History Society set up a committee to investigate and record temporary geological sections in the London area. Among the earliest to be dealt with was the excavation in flood-plain gravel for the foundations of the Concert Hall for the Festival of Britain (1951). Samples of 100-200 grams were taken from two sandlentieles for heavy mineral investigation, and material from one of these, passing 60 mesh and washed by laevigation, yielded, on separation by means of a bromoform-benzene mixture of density about 2"73, an assemblage with abundant garnet, tourmaline, zircon, and kyanite, very occasional staurolite, cassiterite, and fluorite, and moderately abundant collophane.

Belgic Bronzes and Pottery found at Felmersham-on-Ouse, Bedfordshire

The find of pottery and bronzes described in this paper was made in Catuvellaunian territory (fig. 1), on the north bank of the Ouse near Felmersham Bridge, in Shanbrook parish, Bedfordshire. At this place the river makes a gentle bend southwards towards the village of Felmersham. Following the Belgic predilection for riverine settlement, the site to which the find belongs was established on well-developed flood-plain gravels situated on the inner margin of this curve. Here in January 1942, from the gravel-digging exploited by Mr. A. E. C. Howard of Bedford, the excavating machine simultaneously disgorged the following objects:A bronze bucket-handle and two bronze bucket-escutcheons in the shape of cow-heads (fig. 2).A bronze spout in the shape of a fish-head (fig. 3).A damaged bronze bowl (no. 1) with one of the two original attachments for holding swinging ring-handles (pl. VII, a, b).Fragments of another bowl (no. 2), including parts of the rim and shoulder (pl. VII, c).A flat plate of thin bronze, in shape the segment of a circle, with traces of solder on both sides (pl. VI, b).Three pieces of curved bronze rim-mounting of U-section (pl. VI, a).Three pieces of flat bronze ribbon and an irregular piece of bronze plate of the same thinness (pl. VI, a).Some thirty potsherds, the lower jaw of a young pig, part of the tibia of another young animal, probably a horse, and some pieces of burnt clay (fig. 11 ).

Four Flint Implements

It is now some years since I first drew attention to the discovery of certain very perfect leaf-shaped blades, of Early Solutré type, at Ipswich. These specimens were found during the putting in of deep foundations for a chimney-shaft at the Ipswich Corporation's Power Station in Constantine Road. The blades, which are unabraded, came from below a considerable thickness of gravel, where, it may be supposed, there at one time existed a land surface inhabited by Early Solutré man. This land surface is now buried beneath the Flood Plain terrace of the River Gipping, and is well below the water-table of the locality. It is clear, therefore, that since Early Solutré man lived in the Gipping Valley, a marked sinking of the East Anglian area has taken place. Following the appearance of my paper upon the blades found at Constantine Road, Ipswich, other specimens which, by their forms and manner of flaking, are also referable to Early Solutré times have been recovered. These examples have come to light about a mile farther up the valley. The site is situated on the south-west of the Bramford Road where the Flood Plain gravel is being exploited by Messrs. Warren Livingstone, Ltd. The gravel is raised by means of a powerful suction-pump, and, from my observations at Bramford Road, I entertain little doubt that, as at Constantine Road, the Flood Plain Early Solutré land-surface is present there below the Flood Plain gravel.

A Final Note on the Ebbsfleet Channel Series

Both geologists and archaeologists will be under a debt of BOTH gratitude to Messrs. King and Oakley for their recent paper on the Pleistocene sequence of the lower part of the Thames Valley (I). Not only have they conveniently summarized the results obtained by other field-workers, but they have contributed two postulates of great importance. These are: (a) the probability of a major period of erosion between the deposition of the Lower Loam and the Middle Gravel of the Boyn Hill Terrace succession; and (6) the recognition of a period of erosion between the formation of the Lower Flood Plain Gravel and the Post-Pleistocene alluvial beds.

Artefacts of Upper Palæolithic Facies from Coombe Deposits underlying the Gravels of the Flood Plain

I HAVE lately recorded in these columns1 the occurrence, south of the Thames, of a ‘floor’ yielding flint implements of Upper Palaeolithic types and fragments of coarse pottery inter-stratified between Coombe Deposits. The relation of these Coombe Deposits to the Gravels of the Flood Plain has been clearly demonstrated, north of the Thames, by the officers of the Geological Survey.2 For there the Flood Plain Gravels may be seen overlying the Coombe Deposits; the latter, as at Greenhithe, consisting, in ascending order, of Coombe Rock, coarse gravel, brickearth, and stony loam containing ‘rafts’ of Coombe Rock.

Research Items

Ancient Man in the Gipping-Orwell Valley.—The Proceedings of the Prehistoric Society of East Anglia for 1930, vol. 6, pt. 3, contains a study of the deeply buried deposits of the non-tidal valley of the Gipping above Ipswich and the tidal part of the valley of the Orwell below Ipswich. These deposits lie in deeply cut and steep-sided channels, filled apparently with glacial material buried beneath the deposits lying on the floor of the present valley. They are evidently of high antiquity. (I.) The Gipping Valley. (1) After the retreat of the ice which laid down the Upper Chalky Boulder Clay (third glacial epoch of East Anglia) and while climatic conditions were still severe, Aurignacian peoples were living in the valley. Afterwards 11 ft. of gravel was laid down, with an increase of cold conditions. It is possible that one bed represents the fourth glacial epoch of East Anglia, and that the flint implements it contains were swept down and redeposited over the slightly less old implements found beneath. (2) The Flood Plain Terrace. In ascending order are encountered (a) a Combe Capelle floor of Early Mousterian age, (b) Early Solutrean, fine flint blades in loam belonging to the third inter-glacial period below Flood Plain gravel. Mammalian bones, among them the mammoth, belong possibly to this horizon. (3) The gravel of the Flood Plain Terrace of post-Early-Solutrean age contains a large number of derivative flakes and implements, to be associated with the passing away of the fourth glacial epoch, the Boulder Clay of which contains implements of upper pal¦olithic type. (4) The beds above the Flood Plain Terrace. From the loamy peat deposit have been recovered a number of long, thin blades of flint probably of Magdalenian age. (II.) The tidal portion of the Orwell Valley. Overlying the basal gravel is a bed of compact peat, from which it is probable there came a skull comparable with the Tilbury skull and possibly contemporary with the Combe Capelle type of implement. Above the lower peat is a shingly gravel capped by peat and mud in alternate layers. From the base of the alluvium probably came implements exhibiting affinities with the Magdalenian. In both the Gipping and Orwell valleys the neolithic period is represented, both geologically and arch¦ologically only in the superficial beds.