Research Report On Marine Calcareous Microfossils

It was assumed that these carbon values were unaffected by the diagenesis since aqueous fluids typically have an insignificant amount of carbon in comparison to carbonate rocks. In addition, stratigraphic mapping showed that there was no tectonic activity in this area that would have affected diagenesis either. Results indicated that the proportion of organic carbon to total carbon burial changed from roughly 0.5 before the glacial deposits to virtually 0 immediately after. [Hoffman et al., 1998]. These numbers indicate that life struggled during this interval and the snowball Earth theory might explain why. Oceanic photosynthetic bacteria and eukaryotes would have been severely reduced because global ice cover would have blocked the sun making photosynthesis very difficult. (maybe also use top of 1344 to talk about theory on how snowball earth ended; Should I maybe use separate part of paper for theory and evidence. They tie together pretty

The purpose of this experiment was to observe the light that the Tomopteris emits. They collected Tomopteris from Monterey Bay off the coast of California. They then stimulated the Tomopteris to produce light so that they could observe the light that it produced. The researchers took photos and measured the amount of light that was emitted per Tomopteris. One interesting discovery was a Tomopteris that emits a blue light which is rare since most Tomopteris emit a yellow-orange light. The researchers tried to create explanations as to why this Tomopteris emits blue light. They think that “different protein complements may be responsible for the light in different species”. However, this isn’t their only explanation for this rare blue emitting Tomopteris. The other explanation is that “this could potentially reflect different ecological roles of the two light colors”. Researchers concluded that with further testing the blue-light emitting Tomopteris may be considered a species of their own.

Bradbury’s (1967) dissertation research was the first comprehensive study of Zuni Salt Lake maar. Based on a radiocarbon age of 22.9 ± 1.4 ka 14C yr BP (Haynes et al., 1967) on aquatic, calcareous algae from Zuni Salt Lake lacustrine deposits 15 m above the present lake level, he concluded that the Zuni Salt Lake maar formed during the late Pleistocene. This single date provided a maximum age for the Zuni Salt Lake maar but has long been viewed as suspect because of probable hardwater carbon-reservoir effects. Subsequent argon dating of Zuni Salt Lake volcanic rocks resulted in low-resolution plateau ages of 114 ± 38 ka and 86 ± 31 ka (McIntosh and Cather, 1994).

British Colombia in Canada, much like California in the United States, used to be a shallow sea and home to much sea life and is now home to thousands of marine animal fossils. For this reason it is believed that Dinosaur Provincial Park consisted of a lot of sands and muds that are characteristic of costal plains (Sues, Henderson, & Tanke, 2010, pg. 1292). When Sues, Henderson, and Tanke (2010) where going about measuring fossil shifts and the amount of fossils that have been lost they took into account the amount of soil that erodes away every year, the vertical and horizontal distribution fossils found within the park, and large landmarks such as rivers and glaciers that could effect fossils in the area (pg.1293). Accounting for these factors

The base of IIIb1 appears slightly oxidized and yielded an age of 2277± 36 14C yr BP. Above this is a ~60-cm-thick, organic-rich “black mat” (IIIb2) consisting of multiple thin beds containing varying amounts of plant matter including both decomposed humic material and uncharred plant macrofossils that constitute a significant proportion of the sediment volume in the most organic-rich deposits. The IIIb2 black mat was formed between 1934 ± 29 14C yr BP and 1759 ± 25 14C yr BP, with the most organic-rich portion predating 1833 ± 36 14C yr BP. Organic carbon content of the black mat varies, but the highest values are ~2%. Plant remains in IIIb2, consisting mostly of bulrush achenes and pollen, indicate emergent aquatic floodplain vegetation, and the unidentifiable stem fragments ubiquitous throughout the layer are likely also bulrush (Figure 8). Faunal remains within IIIb2 at 11-37 include snail and ostracode species indicative of marshy conditions (Table 4). From the base of IIIb1 to the sharp upper boundary of the IIIb2 black mat, a trend of decreasing calcium carbonate, increasing gypsum, and increasing organic carbon is evident. Gypsum content ranged from 3.7–16.6% and occurred as tiny clumps of intergrown lathe crystals, whereas carbonate content ranged from ~4–13% and occurred as small soft

(2.) Dehairs, F., Fripiat, F., Cavagna, A., Trull, T. W., Fernandez, C., Davies, D., & ... Elskens, M. (2015). Nitrogen cycling in the Southern Ocean Kerguelen Plateau area: evidence for significant surface nitrification from nitrate isotopic compositions. Biogeosciences, 12(5), 1459. doi:10.5194/bg-12-1459-2015

Using this approach, we estimated percent contribution of terrestrial organic carbon sources in juvenile Chinook salmon and interpreted the dynamics of its use spatially and temporally in the Merced River. Our research indicated that the contribution of the terrestrial vegetation to juvenile Chinook salmon growth was highly variable across locations and years. In the river-marsh-estuary San Francisco complex, Cloern et al. (2002) concluded that carbon stable isotopes could not be used as biomarkers for tracing the origins of organic matter, due to high variability in isotope ratios within-plant groups and high dissimilarity between isotopic signatures of primary producers and their organic-matter pools in the seston and sediments. Research in aquatic ecosystems using stable isotopes has shown that there can be significant between and even within-year variation in the isotopic signatures of primary production sources (Post

The Peninsular terrane is a Triassic to Jurassic island-arc complex that was accreted to the North American craton by the Early Cretaceous (Detterman and Reed, 1980; Jones et al., 1987; Ridgway et al., 2002; Trop et al., 2002, 2005; Clift et al., 2005). The terrane includes mafic to andesitic flows and volcaniclastic rocks, limestone, and mudstone. These rocks structurally overlie and are intruded by Jurassic plutonic rocks of the Talkeetna arc (Reed and Lanphere, 1973; Reed et al., 1983; Rioux et al., 2010). The plutonic rocks include gabbroic to granitic compositions, but are dominated by quartz diorite and tonalite rocks (Detterman and Reed, 1980; Reed et al., 1983).

Glaciation that are widespread can be identified based on the subglacial tillite, which is a thick layer of sediments that settle down beneath glaciers or ice caps. On top of this subglacial tillite layer is deposited marine carbonate, also known as cap carbonate. Based on their paleolatitude designated by glacial sediments’ paleomagnetism, it can be determined that these deposits are from equator region. The interaction between two types of sediments, marine (like carbonate) and subgacially deposited sediments, indicate that the glaciers had approached marine coastlines.

Since the industrial revolution, anthropogenic inputs of carbon dioxide to the atmosphere have increased dramatically. Concentrations in the atmosphere have risen 40% from 1750 to 2011, reaching record highs of 390.5 ppm (Stocker, et al., 2013). Due to this, the amount of dissolved CO2 in the oceans has also increased causing acidification of the oceans which can have several effects, mainly on calcifying organisms. Climate change has also influenced the stratification of the oceans due to density changing affecting nutrient distribution. So far, although a number of methods have been explored, there have been no solutions that don’t have their own issues.

Ammonite taxa often occur in narrow time ranges, arguably making them the best index fossils to determine the ages of strata of certain time intervals (Callomon, 2003). The fossil remnants of ammonites act as the major basis for the identification of Jurassic and Cretaceous strata in the Sverdrup Basin, reinforced by the presence of bivalves, dinoflagellates, and foraminifera (Galloway et al., 2013). While macrofossils such as ammonites are used to define every stage of the Jurassic and Cretaceous periods in the Sverdrup Basin, detailed chronostratigraphy is limited by the rare occurrence of ammonite fauna (Callomon, 2003). This may be due to the colder climate conditions of the Arctic Boreal Sea relative to the subtropical conditions of the

1. One of the paramount topics we have covered in this course is oceanography (no surprises there). Rather than thinking of oceanography as “just” the study of the ocean, I have always viewed oceanography as the study of marine biology, marine chemistry, marine geology and marine physics. Before diving into any sort of detail, one can see (from the above) that oceanography incorporates four fundamental sciences into one topic; therefore, when asked to list three ways in which marine geology and marine chemistry interrelate, the possibilities are endless. Because we are to list just three examples, I am going to focus my answer on the Earth’s composition/layers. The first way these two fields interrelate is though convection currents (mantle). Density and temperature are two topics central to chemistry. Because density and temperature, along with depth, play a critical role in plate movement (geology), the plate tectonic theory is one example. The second way is through radioactive decay. Specifically, we use radioactive dating (e.g., isotope dating and half-lives) to determine the exact age of a specific geological structures. The third way these two fields interrelate is in determining the composition of the Earth’s inner core. I saved this example for last because it shows how marine physics can also be interrelated in marine chemistry and marine geology. We [scientific community] have a sound understanding of the Earth’s composition because of mass, density and temperature

The main factors in this climate change are observed to be the increase in temperatures and the resulting acidification of the oceans. The previously mentioned changes and others in the report are readily observable, such as the uptake of anthropogenic carbon since 1750 that has led to the ocean becoming more acidic, with an average decrease in pH of 0.1 units and in some instances blatantly obvious, even to the average layperson. It is difficult to conclude what the rate of change in the future will be and the effects of observed ocean acidification on the marine biosphere.

In Mesozoic era, there were only two continents present in the world. Mesozoic era’s climate compares to the Paleozoic era is more uniform and there were no trace of glacial isotopes observed in that period. That is because of the

By testing sediment and recording whether it was deposited under conditions of normal polarity and then measuring successive layers, we can build a time chart. By matching different charts from different areas with similar fossils, a more global correlation can be made.