Estimating <Emphasis Type="Italic">probable maximum loss</Emphasis> from a Cascadia tsunami

The Cascadia margin is capable of generating large magnitude seismic-tsunami. We use a 1:500 year tsunami hazard flood layer produced during a probabilistic tsunami hazard assessment as the input to a pilot study of the vulnerability of residential and commercial buildings in Seaside, OR, USA. We map building exposure, apply the Papathoma Tsunami Vulnerability Assessment Model to calculate building vulnerability and estimate probable maximum loss (PML) associated with a 1:500 year tsunami flood. Almost US$0.5 billion worth of buildings would be inundated, 95% of single story residential and 23% of commercial buildings would be destroyed with PML’s exceeding US$0.5 billion worth of buildings would be inundated, 95% of single story residential and 23% of commercial buildings would be destroyed with PML’s exceeding US116 million. These figures only represent a tiny fraction of the total values of exposed assets and loss that would be associated with a Cascadia tsunami impacting the NW Pacific coast. Not withstanding the various issues associated with our approach, this study represents the first time that PML’s have ever been calculated for a Cascadia type tsunami, and these results have serious implications for tsunami disaster risk management in the region. This method has the potential to be rolled out across the United States and elsewhere for estimating building vulnerability and loss to tsunami.     

Model Pile Groups Under Oblique Pullout Loads – an Investigation

Experimental investigations on model pile groups of configuration, 1 × 1(single pile), 3 × 1, 2 × 2 for embedment length to diameter ratio, L/d = 38, were conducted in uniform dry medium dense Ennore sand. The spacing of piles in the groups varied from 3 to 6 pile diameter. Soil–pile friction angles were δ = 16° and 28°. The pile groups were subjected to oblique pulling loads at angles θ = 0°, 30°, 60° and 90° with the vertical central axis of the groups. The load–displacement response, oblique ultimate pulling resistances have been qualitatively and quantitatively studied. The inclinations of the load, at which maximum oblique resistance for the groups were observed, have been reported. Predictions of ultimate resistance of pile groups under uplift, lateral and oblique pulling loads have been carried out respectively by the methods of Patra and Pise (2002) (Electronic Journal of Geotechnical Engineering, 8, Bundle B), Patra and Pise (2001) (Journal of Geotechnical and Geoenvironmental Engineering ASCE, 127(6), 481–487) and Chattopadhyay and Pise (1986c) (Proceedings of IST East Asian Conference on Struct Engineering and Const., Vol. 1, pp. 1632–1641). A comparison of the measured values of the Writers and others with the predicted values showed reasonable agreement.     

Tsunami magnitudes in Taiwan, the Philippines and Indonesia

The regional characteristics of tsunami magnitudes in the SE Asia region are discussed in relation to earthquake magnitudes during the period from 1960 to 1994. Tsunami magnitudes on the Imamura-Iida scale are investigated by the author's method (Hatori 1979, 1986) using the data of inundation heights near the source area and tide-gauge records observed in Japan. The magnitude values of the Taiwan tsunamis showed relatively to be small. On the contrary, the magnitudes of tsunamis in the vicinities of the Philippines and Indonesia exceed more than 1–2 grade (tsunami heights: 2–5 times) compared to earthquakes with similar size on the circum-Pacific zone. The relation between tsunami magnitude, m, and earthquake magnitude, M _s, is expressed as m = 2.66 M _s– 17.5 for these regions. For example, the magnitudes for the 1976 Mindanao tsunami (M _s= 7.8, 3702 deaths) and the 1992 Flores tsunami (M _s= 7.5, 1713 deaths) were determined to be m = 3 and m = 2.5, respectively. The focal depth of tsunamigenic earthquakes is shallower thand< 36 km, and the detectively of tsunamis is small for deep earthquakes being d > 40 km. For future tsunamis, it is indispensable to take precautions against shallow earthquakes having the magnitudes M _s> 6.5.     

Tsunami hazard in the Eastern Mediterranean: strong earthquakes and tsunamis in Cyprus and the Levantine Sea

A modern tsunami catalogue has been compiled for the region of Cyprus-Levantine Sea in which 24 certain or possible local tsunamis are listed from antiquity up to the present time, while six regional tsunamis, generated in the Hellenic arc, are documented which affected the region. Another set of 13 doubtful events not included in the catalogue are discussed. Tsunami intensities k and K were re-evaluated using the classic 6-grade and the new 12-grade intensity scales, respectively. The strongest tsunamis reported in the region of interest are those of 551 AD, 749, 1068, 1201, 1222, 1546 and 1759, all occurring along the Levantine coast from Gaza northward, with the exception of the 1222 wave which occurred in the Cyprean arc. The causative earthquakes, however, occur on land and are associated with the left-lateral strike-slip Levantine rift and, as such, remain unexplained. In this paper we speculate on the mechanism of these events. A second tsunami zone follows the Cyprean arc, where the situation of subaqueous seismogenic sources favours the generation of tsunamis by co-seismic fault displacements. Submarine or coastal earth slumping, however, may be an additional tsunamigenic component. Based on historical data, the average tsunami recurrence in the Cyprus-Levantine Sea region is roughly estimated to be around 30 years, 120 years and 375 years for moderate (k/K ≥ 2/3), strong (k/K ≥ 3/5) and very strong (k/K ≥ 5/8) events, respectively. The rate of tsunami occurrence equals 0.033, 8.3 × 10⁻³ and 2.7 × 10⁻³ events/year for intensity k/K ≥ 2/3, 3/5 and 5/8, respectively. For a Poissonian (random) process the probabilities of observing at least one moderate, strong or very strong tsunami are 0.28, 0.01 and 3 × 10⁻³ within 1 year, 0.81, 0.34 and 0.13 within 50 years and 0.96, 0.56 and 0.24 within 100 years, respectively. The tsunami potential in the Cyprus-Levantine Sea area is low relative to other Mediterranean tsunamigenic regions. However, the destructiveness of some historical events indicates the need to evaluate tsunami hazard by all available means. In addition, remote tsunamigenic sources, such as those of 1303 and 1481 in the eastern Hellenic arc, are able to threaten the coasts of the Cyprus-Levantine region and, therefore, such regional tsunamis should be taken into account in the evaluation of the tsunami risk of the region.     

Confidence levels for tsunami-inundation limits in northern Oregon inferred from a 10,000-year history of great earthquakes at the Cascadia subduction zone

To explore the local tsunami hazard from the Cascadia subduction zone we (1) evaluate geologically reasonable variability of the earthquake rupture process, (2) specify 25 deterministic earthquake sources, and (3) use resulting vertical coseismic deformations for simulation of tsunami inundation at Cannon Beach, Oregon. Maximum runup was 9–30 m (NAVD88) from earthquakes with slip of ~8–38 m and M _w ~8.3–9.4. Minimum subduction zone slip consistent with three tsunami deposits was 14–15 m. By assigning variable weights to the source scenarios using a logic tree, we derived percentile inundation lines that express the confidence level (percentage) that a Cascadia tsunami will not exceed the line. Ninety-nine percent of Cascadia tsunami variation is covered by runup ≤30 m and 90% ≤16 m with a “preferred” (highest weight) value of ~10 m. A hypothetical maximum-considered distant tsunami had runup of ~11 m, while the historical maximum was ~6.5 m.     

Tsunami vulnerability assessment in urban areas using numerical model and GIS

Natural disasters can neither be predicted nor prevented. Urban areas with a high population density coupled with the construction of man-made structures are subjected to greater levels of risk to life and property in the event of natural hazards. One of the major and densely populated urban areas in the east coast of India is the city of Chennai (Madras), which was severely affected by the 2004 Tsunami, and mitigation efforts were severely dampened due to the non-availability of data on the vulnerability on the Chennai coast to tsunami hazard. Chennai is prone to coastal hazards and hence has hazard maps on its earth-quake prone areas, cyclone prone areas and flood prone areas but no information on areas vulnerable to tsunamis. Hence, mapping has to be done of the areas where the tsunami of December 2004 had directly hit and flooded the coastal areas in Chennai in order to develop tsunami vulnerability map for coastal Chennai. The objective of this study is to develop a GIS-based tsunami vulnerability map for Chennai by using a numerical model of tsunami propagation together with documented observations and field measurements of the evidence left behind by the tsunami in December 2004. World-renowned and the second-longest tourist beach in the world “Marina” present in this region witnessed maximum death toll due to its flat topography, resulting in an inundation of about 300 m landward with high flow velocity of the order of 2 m/s.     

A Quantitative Assessment of the Human and Economic Hazard from Impact-generated Tsunami

In this article, we assess the human and economic hazard posed by tsunami waves generated from impacts of sub-2 km diameter asteroids. Annually, on average, 182(+197/−123) people will be affected by impact-induced waves with a corresponding infrastructure loss of $18(+20/−12)M/y. Half of the tsunami hazard stems from impactors with diameters less than 300 m. One near Earth asteroid will survive atmospheric transit and strike somewhere into Earth’s oceans every 5880 years, on average. In the mean generic scenario, the tsunami from the impact affects 1.1 million people and destroys $110B of infrastructure.     

Sedimentological and geomorphological effects of the Sumatra–Andaman Tsunami in the area of Khao Lak,southern Thailand

The Sumatra–Andaman Tsunami left distinctive sedimentological and geomorphological signatures in the area of Khao Lak. Fine-grained sediments, predominantly layers of cohesive, carbonate-rich, fine-sandy silt with thicknesses of 1–10 cm, erosionally overlying pre-tsunami sandy soils and sediments, represent the most common tsunami deposits in the study area. Petrographically, they differ significantly from other coastal sediments and affiliated soils. Due to their grain size and corresponding clay mineral content, muddy shelf sediments (sub-wave base) are indicated as a main source. The present results suggest that indications of shelf influence, although varying regionally, might contribute to the identification of fine-grained tsunami sediments and their differentiation from storm sediments. However, the observed differences of tsunami sediments to soils and other coastal sediments, especially with respect to carbonate mineralogy, might disappear in short geological time under conditions of intensive weathering and bioturbation. At Cape Pakarang, hundreds of boulders with up to 24 tons were deposited on the foreshore and upper shoreface. Applying Nott’s (Earth Planet Sci Lett 210:269–276, 2003) formulas, minimum flow velocities of 3.9 m/s are required to transport the largest boulders. The devastating tsunami effect of both, onshore flow and backflow, is documented by damaged human constructions. Geomorphological effects include intensive widening of estuary mouths and the development of erosional channels. Now, estuary mouths are reduced, and erosional channels cut off from the sea due to the formation of a post-tsunami beach ridge.     

海啸和海啸沉积

综述海啸沉积特征,认为岸上细粒海啸沉积物具有以下特点:（1）地层层序上向上变细、减薄;（2）水流方向的重复反向（即重复的双向水流）;（3）含有撕裂的碎屑;（4）较差的分选性;（5）向陆地延伸更远;但将以上任何单一特征看成是海啸沉积的特征性依据都是不恰当的,需要将以上特征结合起来判断,才能作为海啸沉积的依据。而有关岸上巨砾的海啸或是风暴来源,至今仍争论不清,但较一致认为巨砾堤坝复合体是风暴成因。浅水碎屑海啸岩通常为夹在低能稳定状态的背景沉积粉砂—黏土层内的一套独特砂层,可以根据海啸能量的增加到衰减分为Tna—Tnd四个不同单元;而地震海啸岩通常具有震积岩—海啸岩的沉积序列;碳酸盐海啸岩则显示了与海啸入射流和回流相关的冲刷—充填结构。深海的海啸沉积作用机制仍然不清。尽管海啸传播阶段可以产生地中海A型均质岩,但深海海啸岩可能主要与海啸回流有关,如目前讨论最多的K—T撞击海啸岩。尽管目前的研究促进了对海啸的认识,但存在诸如海啸沉积机制仍然不明确,海啸沉积识别依然困难等许多问题,海啸沉积学的进一步发展将为解决这些问题提供坚实基础。     

Tsunami vulnerability assessment of Casablanca-Morocco using numerical modelling and GIS tools

Earthquakes and tsunamis along Morocco’s coasts have been reported since historical times. The threat posed by tsunamis must be included in coastal risk studies. This study focuses on the tsunami impact and vulnerability assessment of the Casablanca harbour and surrounding area using a combination of tsunami inundation numerical modelling, field survey data and geographic information system. The tsunami scenario used here is compatible with the 1755 Lisbon event that we considered to be the worst case tsunami scenario. Hydrodynamic modelling was performed with an adapted version of the Cornell Multigrid Coupled Tsunami Model from Cornell University. The simulation covers the eastern domain of the Azores-Gibraltar fracture zone corresponding to the largest tsunamigenic area in the North Atlantic. The proposed vulnerability model attempts to provide an insight into the tsunami vulnerability of building stock. Results in the form of a vulnerability map will be useful for decision makers and local authorities in preventing the community resiliency for tsunami hazards.     

A physical basis for Pauling's definition of bond strength

 The average strength, s, of the bonded interactions comprising a cation containing oxide anion coordination polyhedron and the value of the electron density, ρ(r _c ), at the bond-critical points are inversely correlated with bond length. In each case, the observed bond lengths, R, were modeled with power-law expressions defined in terms of s/r and ρ(r _c )/r, respectively, where r is the Periodic Table row number of the cation involved in the bonded interaction. On the basis of the close connection between bond strength and the value of the electron density at the bond-critical point, we conclude that bond strength is a direct measure of bond type; the greater its value, the greater the localization of electron density in the binding region and the greater the shared–electron covalent character of the bonded interaction. Received: 15 October 2002 / Accepted: 17 February 2003 Present address:G. V. Gibbs in care of M. Spackman Department of Chemistry, University of New England, Armidale 2351, Australia Acknowledgements The NSF is thanked for supporting this study with grant EAR–9627458. The paper was written while GVG was a Visiting NSF Scholar at The University of Arizona. The faculty and graduate students of the Department of Geosciences and Bob Downs and Marelina Stimpf in particular are thanked for making the visit great fun.     

Area-scale landslide hazard and risk assessment

The paper deals with a methodology for quantitative landslide hazard and risk assessments over wide-scale areas. The approach was designed to fulfil the following requirements: (1) rapid investigation of large study areas; (2) use of elementary information, in order to satisfy the first requirement and to ensure validation, repetition and real time updating of the assessments every time new data are available; (3) computation of the landslide frequency of occurrence, in order to compare objectively different hazard conditions and to minimize references to qualitative hazard attributes such as activity states. The idea of multi-temporal analysis set forth by Cardinali et al. (Nat Hazards Earth Syst Sci 2:57–72, 2002), has been stressed here to compute average recurrence time for individual landslides and to forecast their behaviour within reference time periods. The method is based on the observation of the landslide activity through aerial-photo surveys carried out in several time steps. The output is given by a landslide hazard map showing the mean return period of landslides reactivation. Assessing the hazard in a quantitative way allows for estimating quantitatively the risk as well; thus, the probability of the exposed elements (such as people and real estates) to suffer damages due to the occurrence of landslides can be calculated. The methodology here presented is illustrated with reference to a sample area in Central Italy (Umbria region), for which both the landslide hazard and risk for the human life are analysed and computed. Results show the powerful quantitative approach for assessing the exposure of human activities to the landslide threat for a best choice of the countermeasures needed to mitigate the risk.An erratum to this article can be found at     

The single-crystal,polarized-light,FTIR spectrum of stoppaniite,the Fe analogue of beryl

We report here a single-crystal polarized-light study of stoppaniite, ideally (Fe,Al,Mg)₄(Be₆Si₁₂O₃₆)(H₂O)₂(Na,□), from Capranica (Viterbo). Polarized-light FTIR spectra were collected on an oriented (hk0) section, doubly polished to 15 μm. The spectrum shows two main bands at 3,660 and 3,595 cm⁻¹; the former is strongly polarized for E ⊥c, while the latter is polarized for E //c. A sharp and very intense band at 1,620 cm⁻¹, plus minor features at 4,000 and 3,228 cm⁻¹ are also polarized for E //c. On the basis of literature data and considering the pleochroic behavior of the absorptions, the 3,660 cm⁻¹ band is assigned to the ν₃ stretching mode and the 1,620 cm⁻¹ (associated with an overtone 2*ν₂ at 3,230 cm⁻¹) band to the ν₂ bending mode of “type II” water molecules within the structural channels of the studied beryl. The sharp band at 3,595 cm⁻¹ is not associated with a corresponding ν₂ bending mode; thus it is assigned to the stretching vibration of O–H groups in the sample. The minor 4,000 cm⁻¹ feature can be assigned to the combination of the O–H bond parallel to c with a low-frequency metal-oxygen mode such as the Na–O stretching mode. The present results suggest that the interpretation of the FTIR spectrum of Na-rich beryl needs to be carefully reconsidered.     

Ten-year progress of Chinese polar geodesy: 1996–2006

The ten-year progress of Chinese polar geodesy from 1996 to 2006 is summarized. Research on plate motion, crustal movement, orbit determination, and atmospheric monitoring, including the ionosphere and troposphere, were performed using GPS data of the Great Wall Station, Zhongshan Station and Yellow River Station. GPS was also applied in the Amery Ice Shelf, Grove Mountains and Dome A expeditions to study ice dynamics. During the 2004/2005 austral summer season, the absolute gravity and relative gravity were measured at the Great Wall Station with precision within ± 3 × 10⁻⁸ ms⁻² and ± 10 × 10⁻⁸ ms⁻² respectively. The tide gauge, which was set up in Zhongshan Station to monitor sea level change in 2000, recorded the 2004 Indian Ocean tsunami. SAR interferometry was applied to build the DEM of ice sheet and monitor ice flow in the polar region. __________ Translated from Advances in Earth Science, 2007, 22(8): 784–790 [译自: 地球科学进展]     

The possibility of a tsunami on Lake Baikal

Based on the general physical nature of tsunami generation, it is established that it is an attribute of seismically hazardous areas and regions adjacent to large water reservoirs and is threatening to the population and infrastructure of the coastal zones. The main preconditions and possibilities for the occurrence of tsunami on Lake Baikal are considered: the information on earthquakes in the Baikal hollow during the instrumental-historical period (1724–2011) is generalized in the map of epicenters of shocks of magnitude M ⩾ 5 and histograms of the distribution of numbers of shocks with respect to magnitude. It is shown that the tsunami waves start forming on Baikal if the earthquake magnitude M is ≈5, but since a system of tsunami monitoring on Baikal is absent, it can be observed only during the strongest earthquakes of M > 7. The catastrophic Tsagan earthquake (1861, M ≈ 7.5) is given as an example. It happened near the eastern coast of Lake Baikal and caused a tsunami with people’s deaths.     

French Polynesia Tsunami Warning Center (CPPT)

Since 1964, the Geophysical Laboratory in Tahiti has been charged with the responsibility of issuing tsunami warnings. But this research laboratory is also designed to conduct other missions. One of them is to study an oversee seismicity and volcanism in the South Central Pacific. For this activity the Geophysical Laboratory, which is also the French Polynesia Tsunami Warning Center (Centre Polynésien de Prévention des Tsunamis — CPPT), processes the data recorded by the Polynesian Seismic Network which includes 21 short-period stations, 4 broad-band three-component long period stations, and 2 tide gauge stations. These stations are, for the most, telemetered to CPPT in Tahiti which is equipped wilh data processing capabilities.At CPPT, Tsunami Warning is based on the measurement of the Seismic Moment through the mantle magnitudeM _m and the proportionality of observed tsunami height to this seismic moment.The new mantle magnitude scale,M _m, uses the measurement of the mantle of Rayleigh and Love wave energy in the 50–300 s period range and is directly related to the seismic moment throughM _m = logM _o – 20. Knowledge of the seismic moment allows an estimation of a range of high seas amplitudes for the expectable tsunami.The relation that estimates the tsunami height according to the seismic moment is based on the normal mode tsunami theory but also fits a dataset of 17 tsunamis recorded at Papeete (PPT) since 1958. This procedure is fully automatic: a computer detects, locates and estimates the seismic moment through theM _m magnitude and, in terms of moment, gives an amplitude window for the expected tsunami. These-several operations are executed in real time. In addition, the operator can use historical references and, if necessary, acoustic T waves.This automatic procedure, which has been operating at the CPPT since 1986, is certainly transposable and applicable to other tsunami warning centers that issue warnings for earthquakes detected more than 1000 km away, and has significant potential in the regional field.     

Coupling of oceanic and continental crust during Eocene eclogite-facies metamorphism: evidence from the Monte Rosa nappe,western Alps

High precision U–Pb geochronology of rutile from quartz–carbonate–white mica–rutile veins that are hosted within eclogite and schist of the Monte Rosa nappe, western Alps, Italy, indicate that the Monte Rosa nappe was at eclogite-facies metamorphic conditions at 42.6 ± 0.6 Ma. The sample area [Indren glacier, Furgg zone; Dal Piaz (2001) Geology of the Monte Rosa massif: historical review and personal comments. SMPM] consists of eclogite boudins that are exposed inside a south-plunging overturned synform within micaceous schist. Associated with the eclogite and schist are quartz–carbonate–white mica–rutile veins that formed in tension cracks in the eclogite and along the contact between eclogite and surrounding schist. Intrusion of the veins at about 42.6 Ma occurred at eclogite-facies metamorphic conditions (480–570°C, >1.3–1.4 GPa) based on textural relations, oxygen isotope thermometry, and geothermobarometry. The timing of eclogite-facies metamorphism in the Monte Rosa nappe determined in this study is identical to that of the Gran Paradiso nappe [Meffan-Main et al. (2004) J Metamorphic Geol 22:261–281], confirming that these two units have shared the same Alpine metamorphic history. Furthermore, the Gran Paradiso and Monte Rosa nappes underwent eclogite-facies metamorphism within the same time interval as the structurally overlying Zermatt-Saas ophiolite [∼50–40 Ma; e.g., Amato et al. (1999) Earth Planet Sci Lett 171:425–438; Mayer et al. (1999) Eur Union Geosci 10:809 (abstract); Lapen et al. (2003) Earth Planet Sci Lett 215:57–72]. The nearly identical P–T–t histories of the Gran Paradiso, Monte Rosa, and Zermatt-Saas units suggest that these units shared a common Alpine tectonic and metamorphic history. The close spatial and temporal associations between high pressure (HP) ophiolite and continental crust during Alpine orogeny indicates that the HP internal basement nappes in the western Alps may have played a key role in exhumation and preservation of the ophiolitic rocks through buoyancy-driven uplift. Coupling of oceanic and continental crust may therefore be critical in preventing permanent loss of oceanic crust to the mantle.     

Sporopollen and algae research of core B106 in the northern South China Sea and its paleoenvironmental evolution

Based on the high-resolution sporopollen and algae research of the sediments from core B106 in the northern South China Sea, three sporopollen assemblage zones have been distinguished in ascending order: Zone 1 (294–194 cm): Pinus-Quercus (evergreen)-Gramineae-Polypodiaceae- Pterdium-Dicranopteris. Zone 2 (194–94 cm): Pinus-Quercus (evergreen)-Polypodiaceae-Pteridium- Dicranopteris. Zone 3 (94–4 cm): Pinus-Polypodiaceae-Pteridium-Quercus (evergreen)-Dicranopteris. The three sporopollen zones correspond to three stages of vegetation, climate and paleoenvironment evolution of the northern part of the South China Sea since 11 000 years ago. Combined with AMS ¹⁴C dating, the sporopollen and algae data can be a scientific basis for stratigraphic division and reconstruction of paleoclimate and paleoenvironment in the South China Sea. __________ Translated from Marine Geology & Quaternary Geology, 2007, 27(5): 9–14 [译自: 海洋地质与第四纪地质]     

In search of the mixed derivative ?2 M /? P ? T ( M = G , K ): joint analysis of ultrasonic data for polycrystalline pyrope from gas- and solid-medium apparatus

Elastic wave velocities for dense (99.8% of theoretical density) isotropic polycrystalline specimens of synthetic pyrope (Mg₃Al₂Si₃O₁₂) were measured to 1,000 K at 300 MPa by the phase comparison method of ultrasonic interferometry in an internally heated gas-medium apparatus. The temperature derivatives of the elastic moduli [(∂Ks/∂T) _P = −19.3(4); (∂G/∂T) _P = −10.4(2) MPa K⁻¹] measured in this study are consistent with previous acoustic measurements on both synthetic polycrystalline pyrope in a DIA-type cubic anvil apparatus (Gwanmesia et al. in Phys Earth Planet Inter 155:179–190, 2006) and on a natural single crystal by the rectangular parallelepiped resonance (RPR; Suzuki and Anderson in J Phys Earth 31:125–138, 1983) method but |(∂Ks/∂T) _P | is significantly larger than from a Brillouin spectroscopy study of single-crystal pyrope (Sinogeikin and Bass in Phys Earth Planet Inter 203:549–555, 2002). Alternative approaches to the retrieval of mixed derivatives of the elastic moduli from joint analysis of data from this study and from the solid-medium data of Gwanmesia et al. in Phys Earth Planet Inter 155:179–190 (2006) yield ∂² G/∂P∂T = [0.07(12), 0.20(14)] × 10⁻³ K⁻¹ and ∂² K _S /∂P∂T = [−0.20(24), 0.22(26)] × 10⁻³ K⁻¹, both of order 10⁻⁴ K⁻¹ and not significantly different from zero. More robust inference of the mixed derivatives will require solid-medium acoustic measurements of precision significantly better than 1%.