<p> Oceans are acidifying as atmospheric CO₂ is drawn down. This process, known as ocean acidification (OA), is well known and documented. Over the next 100 years, pH of the surface ocean is projected to decrease by up to 0.35 units. This CO₂ draw down has a direct effect on dissolved inorganic carbon (DIC) balance in the ocean. OA is expected to impact calcifying organisms that rely on constituencies of the DIC system, specifically carbonate ion [CO₃^2-]. It is clear that externally calcified structures, such as coral skeletons, bivalve shells, etc., will be significantly affected as pH, and consequently [CO₃^2&minus;], of the oceans decline. What is unclear, however, is how these changes will impact internally calcified structures, such as earstones (otoliths) of teleost fish. This dissertation examines the impacts of OA on otolith mineralization in larval reef fish (<i>Amphiprion clarkii</i>and <i>A. frenatus </i>). This research included the development of a laboratory controller system for control of experimental aquaria pH through pCO₂ dosing, exposure of larvae from hatch to settlement under various pCO2 treatments and evaluation of otolith structure and morphology across treatments within a single genus. </p><p> No standard method for pH-stat CO₂ dosing controllers existed prior to this study. Incorporating low-cost, flexible hardware allowed high precision and accuracy pH controllers to be designed and implemented. Following system stability studies, we found that our system performed at or beyond the level of control exhibited in the literature. </p><p> Two species of clownfish, <i>Amphiprion clarkii</i> and <i> A. frenatus,</i> were exposed to different pCO₂ conditions, reared to settlement and otoliths extracted and studied. I found that the sagittae (largest of the 3 otolith types) of both species exhibited circularity changes towards more oblong otoliths under increased pCO₂. For <i> A. clarkii,</i> I found a significant negative relation between pCO₂ and lapilli otolith circularity, indicating a shift toward more circular lapilli under increased pCO₂. Since lapilli are critical to gravisensing in teleosts these results explain my anecdotal observations that, at high pCO₂, larvae exhibited lethargic, uncoordinated swim patterns. The core development of otoliths (sagittae, lapilli, and asterisci) from both species was analyzed using SEM imagery. Otolith images were scored by 6 independent readers for core development (poorly developed to well-developed). Otolith scores were regressed against aragonite saturation state (&ohm;_Ar). Results showed significant and strong relations between &ohm;Ar and development score, indicating a shift toward protruding, unorganized crystal clusters within the core under high pH/low &ohm;_Ar. </p><p> This research is the first to comprehensively examine the impact of OA on the otolith system in larval fish. The research revealed direct impacts on otolith structure and morphology as well as mineralogy. These changes will directly impact survival of the larvae. It remains unknown whether the otolith system recovers post-settlement or whether the anecdotal observations on swimming behavior are directly related to otolith deformation. Future research will include exploration of these relations across genera as well as more deeply examine the recovery of the system and behavioral impacts of otolith deformation across life stages.</p>

The Ruttan Cu-Zn mine produced approximately 30 million tons of fine-grained tailings over 30 years. Since the closure of the mine in 2002, the tailings have been systematically dewatered through trenches which drain into Ruttan Lake and into the open pit and underground mine workings. This study evaluated the evolution of the tailings of Cell 3, which was underwater in 2002, and Cell 2, which was already dry and oxidized. Dewatering the submerged tailings in Cell 3 resulted in measureable changes in acidification in pore and shallow groundwater from rapid oxidation of very fine grained sulphides. Depth profiles of the concentration of metals in dissolved and solid fractions, when compared to other studies, suggest that the tailings in Cell 2 and Cell 3 are in an early stage of oxidation and that these tailings will produce low pH, metal laden water for years.

No description available.

No description available.

The Mudgee-Gulgong district is located within the exposed northeastern margin of the Lachlan Fold Belt in New South Wales. The district was an important gold mining centre in the 1800's and produced up to 1 million ounces of gold, mostly from deep leads. Re-mapping of the area has resulted in a major revision to the stratigraphy and structural knowledge of the area. Significant changes include the recognition of the formerly known Early Devonian Burranah Formation as a Late Ordovician volcanic unit with significant exploration potential for Au-Cu mineralization. Also recognised is a Late Silurian shelf sequence with potential for Au-Cu and base metals overlying the Burranah Formation. The Burranah Formation is a dominantly submarine, volcano-sedimentary succession with a complex internal stratigraphy. Two main lithofacies associations can be recognised on the magnetic images. A lower package, composed mostly of primary volcanic rocks and minor volcaniclastics is overlain by a package composed dominantly of volcaniclastics and sediments. Small elongate intrusive bodies occur throughout the sequence. Structural interpretation of the area reveals one dominant D2 deformation (Early Carboniferous) that produced meridional to northwest-trending folds, cleavage, thrust faults and oblique-slip faults. A zone of higher strain is developed within the Burranah Formation and is characterised by overturned, tight, F2 folds and considerable shortening. Mapping and interpretation of the area has been greatly assisted by the availability of high resolution gravity, magnetic and radiometric data. The interpretation of magnetic data has considerably enhanced the structural interpretation. Volcanic and intrusive rocks of the Burranah Formation comprise a coherent calcalkaline suite with a dominantly shoshonitic character. In MORB-normalized plots, they display patterns typical of many modern subduction-related volcanics with a marked depletion of Ta and Nb and similar or lower abundances of the heavy REE and Ti. Positive εNd values indicate a mantle source for the shoshonites with little or no crustal contamination. Primary gold mineralization in the district occurs in veins and as disseminations in the structurally more competent rocks adjacent to faults and shear zones in the higher strain zone. Host rocks are generally intrusive monzodiorites, diorites or coherent volcanics and range in age from Late Ordovician to Early Devonian. Sulphur and lead isotope data support a syndeformational model for mineralization with fluids and gold derived from the host rock sequence.

Thesis (M.Sc.) --University of Adelaide, Dept. of Geology, 1961. / Typewritten.

Honors Project--Smith College, Northampton, Mass., 2009. / Includes bibliographical references.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1963. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 137-141).

Thesis (M.S.)--University of Wisconsin--Madison, 1967. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Presented as Thesis (Ph. D.)--University of Wisconsin--Madison, 1930. / Cover title. Reprinted from Journal of the American Society of Agronomy, vol. 24, no. 6 (June 1932). Includes bibliographical references (p. 434).