Geochemistry Commons^™

Nitrate Anomaly In The Upper Nutricline In The Northern South China Sea - Evidence For Nitrogen Fixation, George T. F. Wong, Shi-Wei Chung, Fuh-Kwo Shiah, Chung-Chi Chen, Liang-Saw Wen, Kon-Kee Liu

OES Faculty Publications

[1] Up to 2 μM of nitrate anomaly, N*, were found in the upper nutricline at the South East Asia Time-series Study (SEATS) site in the northern South China Sea (SCS). These concentrations were among the higher values reported in the Pacific and indicate the significant contribution of the remineralization of nitrogen-rich organic matter formed by nitrogen fixation to the nutrient dynamics of the area. The concentrations were systematically higher, by up to 2.5 μM, in the Fall through the early Spring, during the northeast monsoon, than in the Summer, suggesting that the impact of nitrogen fixation was higher during …

A Geochemical Study Of Marine Sediments From The Mac. Robertson Shelf, East Antarctica: Initial Results And Palaeoenvironmental Implications, Peter N. Sedwick, P. T. Harris, L. G. Robertson, G. M. Mcmurtry, M. D. Cremer, P. Robinson

OES Faculty Publications

Sediments from the Antarctic continental margin may provide detailed palaeoenvironmental records for Antarctic shelf waters during the late Quaternary. Here we present results from a palaeoenvironmental study of two sediment cores recovered from the continental shelf off Mac. Robertson Land, East Antarctica. These gravity cores were collected approximately 90 km apart from locations on the inner and outer shelf. Both cores are apparently undisturbed sequences of diatom ooze mixed with fine, quartz-rich sand. Core stratigraphies have been established from radiocarbon analyses of bulk organic carbon. Down-core geochemical determinations include the lithogenic components Al and Fe, biogenic components opal and organic …

On The Linear Relation Between Mb And Ms For Discrimination Between Explosions And Earthquakes, Ali A. Nowroozi

OES Faculty Publications

Summary. The statistical capability of the m_b :M_s, discriminant for the discrimination of earthquake and explosion populations is examined by application of discriminant functions to a group of 83 explosions and 72 earthquakes in Eurasia. Equations are derived for the probability that an event is an earthquake or an explosion. The positive sign of DIS in the decision index equation,

DIS, = 34.3383 - 11.9569 mb_i, + 7.1 161 M_si,

indicates that the event i is an earthquake. Its negative sign indicates that event i is an explosion. The probability of …

Fault Movements And Tectonics Of Eastern Iran: Boundaries Of The Lut Plate, Ali A. Nowroozi, A. Mohajer-Ashjai

OES Faculty Publications

Summary. From 1977 March 21 to 1981 July 28, about 15 earthquakes with M_s ≥6.0 and many earthquakes with M_s≥4.5 have occurred in Iran. The upsurge of seismic activity started following the Khorqu earthquake of 1977 March 21, M,=7.0, south-east of the Fars folded series of Zagros. This shock had a thrust focal mechanism solution indicating the general northward movement of the Arabian plate with respect to the Iranian landmass. It was followed by six major damaging earthquakes in eastern Iran. The earthquakes are associated with extensive faulting which surrounds the Lut plate. (1) The Zarand earthquake …

Trace-Elements In Ilmenite - A Way To Discriminate Provenance Or Age In Coastal Sands, Dennis A. Darby

OES Faculty Publications

Trace elements and Ti percentage in ilmenite grains magnetically separated from modern and late Pleistocene coastal sands of southeastern Virginia and northwestern North Carolina were used to distinguish different deposits. Multivariate analysis of ilmenite composition (Ti, Mn, Mg, Cr, V, Ni, and Cu) from coastal deposits and potential source rivers enabled the identification of dominant source rivers. Using the trace element content of one mineral instead of heavy-mineral suites eliminated most of the hydraulic sorting, selective weathering, and intrastratal solution problems that often obscure heavy-mineral provenance determinations. Most ilmenite grains lacked exsolution or twinning, which are common to ilmenite; however, …

Alkalinity And Ph In The Southern Chesapeake Bay And The James River Estuary, George T. F. Wong

OES Faculty Publications

The ranges of alkalinity and pH in the southern Chesapeake Bay and the James River estuary were 2.25 meq·liter⁻¹ at 32‰ to