Intensity at the Edge

<p>There is an inherent relationship between New Zealanders and the coast and has become part of our culture and identity. The coastal threshold is a place of emersion in time, surface and weathering process of materials and the marks and traces of time, this thesis explores architectural expression on Wellingtons coastline. This project proposes the design of a series of six interventions along Wellington’s south coast. This research explores how architecture can respond to the temporality and extreme contextual conditions of the diverse landscapes. By developing an inherent architectural language of shelter that identifies and embodies the contextual and programmatic narrative, this thesis proposes for the occupation of site through a protective and experiential architecture.</p>

Intensity at the Edge

<p>There is an inherent relationship between New Zealanders and the coast and has become part of our culture and identity. The coastal threshold is a place of emersion in time, surface and weathering process of materials and the marks and traces of time, this thesis explores architectural expression on Wellingtons coastline. This project proposes the design of a series of six interventions along Wellington’s south coast. This research explores how architecture can respond to the temporality and extreme contextual conditions of the diverse landscapes. By developing an inherent architectural language of shelter that identifies and embodies the contextual and programmatic narrative, this thesis proposes for the occupation of site through a protective and experiential architecture.</p>

Identification of Physical and Mineralogical Properties of Riverbank Material at Sand Mining Landslide Sites of Kali Putih River, Blitar

Kali Putih River is a river that is often affected by the eruption of Mount Kelud. The resulting large deposits of volcanic sand materials cause exploitation through uncontrolled sand mines. This will have an impact on potential hazards caused by environmental damage; for example, there have been several cases of riverbank landslides. Based on previous studies, it is important to study the identification of physical characteristics and mineralogy of riverbank materials through laboratory testing. The Gs value was found to be within 2.650-2.697, which can be classified as gravel or sand. According to the AASHTO standard, the classification is coarse-grained soil. By USCS classification, all samples were determined as well-graded sand. Based on the JGS standard, these samples can be classified as Volcanic Soil (VS) and Volcanic Sand (SV). SEM results showed that the grain samples had low sphericity with angular to sub-angular and a bladed-oblate granular form. From X-RD analysis, the mineral composition of samples was dominated by anorthite (CaAl2Si2O8) and albite (Na(AlSi3O8)). Associated with Bowen's Reaction, these compounds are common in young materials when the weathering process is still progressing.

Detecting Deep Rock Weathering

&lt;p&gt;The weathering front, the interface beneath Earth&amp;#8217;s surface where unweathered bedrock is converted into weathered rock, is a zone where chemical disequilibrium results in some of the most intense mineralogical transformations. These are focused into a narrow zone; yet its depth is poorly known due to its inaccessible nature deep beneath the Earth&amp;#8217;s surface. Studies in humid and temperate climate suggest a maximum depth of 20 m for the weathering front in granitoid rock (Hayes et al., 2020).&lt;/p&gt;&lt;p&gt;To explore whether this depth is unique to humid climate we drilled into fractured rock in the semi-arid climate zone of the Coastal Cordillera of Chile. We found deep weathering down to 76 m below the surface which represents one of the deepest weathering fronts ever found. To characterise and quantify rock weathering, we investigated mineralogical and geochemical transformations. Iron (Fe) oxidation and related porosity formation is the first weathering process taking place and hence an indicator for the onset of weathering (Buss et al., 2008). Elemental (&amp;#964;) and bulk loss (chemical depletion fraction, CDF) calculated from the chemical composition reveal multiple zones with more intense weathering compared to bedrock, and where the specific surface area also increases due to formation of secondary solids. Fracturing and the related increase in macro-porosity thus induce these mineralogical and chemical transformations. Below 76 m, bedrock is devoid of weathering features. We suggest that tectonic pre-fracturing in this geologically active region provided transport pathways for oxygen to greater depths, inducing porosity by oxidation. This porosity was preserved throughout the weathering process, as secondary minerals that might fill pores were not formed due to the low fluid flow.&lt;/p&gt;&lt;p&gt;Hayes, N. R., Buss, H. L., Moore, O. W., Kr&amp;#225;m, P. and Pancost, R. D. (2020): Controls on granitic weathering fronts in contrasting climates. Chemical Geology, 535, 119450.&lt;/p&gt;&lt;p&gt;Buss, H.L., Sak, P. B., Webb, S. M. and Brantley, S. L. (2008): Weathering of the Rio Blanco quartz diorite, Luquillo Mountains, Puerto Rico: Coupling oxidation, dissolution, and fracturing. Geochimica et Cosmochimica Acta, 72 (18), 4488-4507.&lt;/p&gt;

Mo mobility in lateritic weathering profiles overlying ultramafic rocks of the East Sulawesi Ophiolite, Indonesia

&lt;p&gt;Molybdenum (Mo) isotopes are known as sensitive recorders for changes in redox conditions because the oxidized form of Mo (Mo VI) is more soluble, whereas its reduced form is more particle reactive. Previous studies suggest that Mo isotopic fractionation during the weathering process is controlled by atmospheric input, Mo host, and bedrock composition. However, Mo isotopic variation and processes influencing fractionation in weathering profiles overlying ultramafic bedrock, the early Earth analog, have yet to be explored. This study explores for the first time (1) Mo behavior and (2) isotopic fractionation in two representative and intensely-weathered lateritic profiles overlying ultramafic bedrock of the East Sulawesi Ophiolite, Indonesia. Mo concentrations measured on samples obtained from laterite successions studied here range between 60 - 537 ppb and are overall higher compared to bedrock values ranging between 9 - 45 ppb. The Mo isotope compositions of laterite samples vary between -0.043&amp;#8240; to -0.161&amp;#8240; &amp;#948;&lt;sup&gt;98&lt;/sup&gt;Mo&lt;sub&gt;NIST3134&lt;/sub&gt;. The overall close to mantle Mo isotopic composition of the laterite samples, their small Mo isotope variability, and the covariation between Mo and Ti concentrations suggest low mobility of Mo during chemical weathering and laterite formation. This low Mo mobility is likely a consequence of a) the low Mo concentration of the ultramafic protolith and b) adsorption of Mo to secondary Fe-Oxides during laterite formation under oxic weathering conditions.&lt;/p&gt;