Geology Reports⌕ Search

Geology topics

J. R. Uzmann

Publications and source records attributed to J. R. Uzmann.

12 recordsLinked to original sources
USGS1984

Submarine sand dunes and sedimentary environments in Oceanographer Canyon.

Observations from research submersibles in the northern part of Oceanographer Canyon reveal the presence of an extensive field of large sand dunes on the canyon floor. The dunes are medium to coarse sand, are oriented across the axis, and the largest of them are as high as 3 m and have wavelengths up to 15 m. Their asymmetry, grain size, and height suggest that they are formed by axial currents flowing up- and downcanyon and that the largest dunes require flows of at least 70 cm/sec. Shelf sand, low in silt and clay content, is transported by currents down and along the canyon walls onto the canyon floor. As the sand enters the canyon, it is mixed with immobile gravel deposits on the canyon rim; lower on the walls, the sand is mixed with silt and clay burrowed by organisms from the semiconsolidated sandy silt that underlies the canyon walls and floor. Upon reaching the canyon floor, the sand is sculpted into bed forms by currents, and the fines are winnowed out and transported out of the canyon. At present, the shelf and canyon walls are being eroded by bottom currents and burrowing organisms, whereas the canyon floor is covered by mobile sand that moves both up and down the axis in this part of the canyon.

Journal of Sedimentary Petrology↗
USGS1980

Geology and biology of Oceanographer submarine canyon.

Santonian beds more than 100 m thick are the oldest rocks collected from the canyon. Quaternary silty clay veneers the canyon walls in many places and is commonly burrowed by benthic organisms that cause extensive erosion of the canyon walls, especially in the depth zone (100-1300 m) inhabited by the crabs Geryon and Cancer. Bioerosion is minimal on high, near-vertical cliffs of sedimentary rock, in areas of continual sediment movement, and where the sea floor is paved by gravel. A thin layer of rippled, unconsolidated silt and sand is commonly present on the canyon walls and in the axis. Shelf sediments are transported from Georges Bank over the E rim and in the Canyon by the SW drift and storm currents; tidal currents and internal waves move the sediment downcanyon along the walls and axis.- from Authors

Marine Geology↗
USGS1966

Clinostomum marginatum in steelhead trout ( Salmo gairdneri ) and cutthroat trout ( Salmo clarki ) in a western Washington lake

Clinostomum marginatum (Trematoda: Clinostomatidae), the yellow grub parasite, was recorded in epizootic proportions from Lynch Lake, King County, Washington, in 1961 and 1962. The parasite larvae occurred principally in steelhead trout (Salmo gairdneri); cutthroat trout (S. clarki) were infected to a relatively minor degree. Fish and snail host populations were destroyed by rotenone and copper sulfate treatments.

Washington↗
USGS1963

In vitro culture of the flagellate protozoan Hexamita salmonis

Trophozoites of Hexamita salmonis, asserted pathogen of juvenile salmonid fishes, were isolated from two species of Pacific salmon hosts and cultured repeatedly in an organic medium saturated with nitrogen. Primary isolates and serial subcultures usually exhibited five- to tenfold population increases per passage.

Science↗
USGS1963

The Hexamita (= Octomitus ) problem: A preliminary report

THE INTESTINAL FLAGELLATE, Hexamita salmonis (Moore), was described in 1922 from trout in hatcheries throughout New York State. At first associated with the so-called whirling disease of brook trout ( Salvelinus fontinalis ), now believed to be a virus disease, Hexamita was subsequently held responsible for practically any otherwise unexplainable mortality in underyearling salmonids. Over the years, Hexamita , ostensibly H. salmonis , has been the most readily recognized parasite of juvenile salmonids.

Progressive Fish-Culturist↗
USGS1961

Rapid counting of nematoda in salmon by peptic digestion

The nematode parasite Anisakis sp . can be recovered, relatively unaltered, from chum salmon musculature by high temperature (52°+2°C.) peptic digestion of the flesh. The procedure, which is presented in detail, appears to be more thorough in isolating the parasite than dissection of the flesh and manual isolation of the worms. In addition, the procedure is rapid, comparatively simple, economical, and suitable for the examination of large numbers of samples. The population of Anisakis sp ., larvae in chum salmon appears to be concentrated in the ventral section of the fish, that is, below the lateral line, which ಟ್ಗ that only the ventral quarters of the fish need to be examined for estimating infection intensity.

International North Pacific Fisheries Commission B↗
USGS1959

The life-cycle of the digenetic trematode, Proctoeces maculatus (Looss, 1901) Odhner, 1911 (Syn. P. rubtenuis [Linton, 1907] Hanson, 1950), and description of Cerceria adranocerca n. sp

The genus Proctoeces was erected by Odhner ( 191 1) to contain Distonium maculatuni Looss, 1901, from Labrus merula and Crenilabrus spp . at Triest. Odhner had found the parasite in Blennius ocellaris at Naples. One adult specimen from Chrysophrys bifasciata and two immature specimens from lulis lunaris taken in the Red Sea, were described as a new species, Proctoeces erythraeus . Dawes (1946) listed P. erythraeus as a synonym of P. maculatus (Looss) , but the species was recognized by Manter ( 1947) on the basis of six specimens he had collected from Calamus calamus and Calamus bajonado at the biological laboratory of the Carnegie Institution at Dry Tortugas, Florida. Several additional species have been de scribed. Fujita ( 1925) reported a metacercaria from the Japanese oyster, Ostrea gigas , as a new species, Proctoeces ostreae . The paper was translated by R. Ph. Dollfus who noted (p. 57) ,“Il est à souhaiter que des recherches chez les poissons mangers de Lamellibranches, sur les côtes de la préfecture d'Hiroshima, permettent de découvrir des exemplaires complètement adultes de Proctoeces ostreae Fuj., chez lesquels l'extension des vitellogènes et les dimensions des oeufs puissent être observées avec précision; il sera alors possible de savoir définitivement si P. ostreae Fuj. doit ou non tomber en synonymie avec P. maculatus (Looss)." Yamaguti (1934) described P. maculatus from Sparus aries , Sparws macrocephalus, Pagrosomus auratus , and Epinephelus akaara in Japan. Several specimens from Pagrosomus auratus , which differed from P. maculatus in larger size, larger eggs, and trilobed ovary, he described as a new species, Proctoeces major . Yamaguti ( 1938) reported P. nzaculatus from Sensicossyphus reticulatus and described a larva from the liver of the pelecypod mollusk, Brachidontes senhausi , as an unidentified member of the genus Proctoeces. Manter ( 1940) described Proctoeces tnagnorus from a single specimen found in the intestine of Caulolatilus ano ,nalus, taken at Cerros Island, Mexico. Hanson ( 1950) identified two specimens collected from Calamus sp . at Bermuda by the late F. D. Barker as Distontuni subtenue Linton, 1907, a species described originally from Calantus calanius in the same area. Comparison of these specimens with those from Tortugas identified by Manter as P. erythraeus established their identity, and P. erythraeus was suppressed as a synonym of Proctoeces subtenue (Linton, 1907). Hanson corrected the statement of Manter (1947), noting that it is the vitellaria, not the uterus, which never extends into the post testicular region.

Biological Bulletin↗
USGS1957

Teratological hermaphroditism in the chum salmon Oncorhynchus keta (Walbaum)

The anomalous condition of hermaphroditism appears to be no less rare in fish than in other normally dioecious animals. Previous records of bisexuality' in the Pacific salmons, Oncorhynchus spp., are few in number despite the intensive study accorded this group. Rutter (1902) reported the condition in two king salmon ( O. tshawytscha ); Crawford (1927) reported the condition in a silver salmon ( O. kisutch ); and Gibbs (1956) described a bisexual steelhead trout ( Salmo gairdneri ) and briefly noted another instance of hermaphroditism in the king salmon. We wish to record an example of this anomaly in the chum salmon ( O. keta ).

Progressive Fish-Culturist↗
USGS1957

New host and locality record for Triaenophorus crassus forel (Cestoda: pseudophyllidea)

The adult form of Triaenophorus crassus Forel, 1868 (= T. robustus Olsson, 1893; = T. tricuspidatus morpha megadentatus Wardle, 1932) occurs as an intestinal parasite in the pike, Esox lucius L., a holarctic species of wide distribution. Preliminary life-history stages include procercoid development in copepods of the genus Cyclops followed by plerocercoid development in the musculature of a variety of coregonid and salmonid fishes. The unsightly appearance of even moderate plerocercoid infections is often sufficient to render fish unacceptable for human consumption. In the prairie provinces of Canada the incidence and intensity of T. crassus infections in the commercially important whitefishes constitute a serious economic problem.

Alaska, British Columbia, Northwest Territories↗