Geology of Chief Joseph Pass, Wyoming: Crest of Rattlesnake Mountain anticline and escape path of the Eocene Heart Mountain slide

ABSTRACT Rattlesnake Mountain is a Laramide uplift cored by Archean gneiss that formed by offset along two reverse faults with opposing dips, the result being an asymmetric anticline with a drape fold of Cambrian–Cretaceous sediments. Rattlesnake Mountain was uplifted ca. 57 Ma and was a structural buttress that impeded motion of upper-plate blocks of the catastrophic Heart Mountain slide (49.19 Ma). North of Pat O’Hara Mountain anticline, Rattlesnake Mountain anticline has a central graben that formed ca. 52 Ma (U-Pb age on vein calcite in normal faults) into which O- and C-depleted fluids propagated upward with hydrocarbons. The graben is defined by down-dropped Triassic Chugwater shales atop the anticline that facilitated motion of Heart Mountain slide blocks of Paleozoic limestones dolomite (i.e., the Ordovician Bighorn Dolomite and Mississippian Madison Limestone) onto, and over, Rattlesnake Mountain into the Bighorn Basin. Heart Mountain fault gouge was also injected downward into the bounding Rattlesnake Mountain graben normal faults (U-Pb age ca. 48.8 ± 5 Ma), based on O and C isotopes; there is no anisotropy of magnetic susceptibility fabric present. Calcite veins parallel to graben normal faults precipitated from meteoric waters (recorded by O and C isotopes) heated by the uplifting Rattlesnake Mountain anticline and crystallized at 57 °C (fluid inclusions) in the presence of oil. Calcite twinning strain results from graben injectites and calcite veins are different; we also documented a random layer-parallel shortening strain pattern for the Heart Mountain slide blocks in the ramp region (n = 4; west) and on the land surface (n = 5; atop Rattlesnake Mountain). We observed an absence of any twinning strain overprint (low negative expected values) in the allochthonous upper-plate blocks and in autochthonous carbonates directly below the Heart Mountain slide surface, again indicating rapid motion including horizontal rotation about vertical axes of the upper-plate Heart Mountain slide blocks during the Eocene.

Mechanism of Spectral Distortion for Real-Time Crack Propagation on Aluminum Alloy Structure

This study investigates four characteristic damage mechanisms of fiber Bragg grating (FBG) sensors, with fatigue crack propagation in aluminum alloy. The multipeak wavelength distinguish algorithm was developed for FBG spectrum quantitative analysis. The results distinguish a subordinate peak skewing significantly, associated with strain patterns along the FBG, corresponding to various crack lengths. For parallel bonded direction grating, the subordinate peak skewing appears at the strain pattern transition region. This is located at the ratio 32%-34% of crack length lying in the crack tip. Meanwhile, the four damage characteristics correspond to subordinate peak skewing. When the strain is distributed along the grating, spectral distortion occurs. In this region, the cubic strain pattern determines the shorter wavelength location of subordinate peaks. This corresponds to the 15%-17% ratio of crack length lying in the grating, causing spectral oscillations.

Diagnostic value of left ventricle strain pattern of hypertensive patients in coronary and cerebrovascular diseases

Association of Electrocardiographic Left Ventricular Strain Pattern with Coronary Artery Disease and Cerebrovascular Accident in Hypertensive Patients Background: Patients diagnosed with hypertension and left ventricular hypertrophy could presented with electrocardiographic changes including criteria of left ventricular hypertrophy, and left ventricular strain pattern( fixed ST depression and T inversion in leads I, avL, V5&6) Objective: To study the impact of electrocardiographic left ventricular strain pattern in hypertensive patient as predictor for coronary artery disease and cerebrovascular accident development. Material and method: a cross sectional hospital based study was conducted during 2012-2017 at Iraqi center for heart diseases including hypertensive patients with normal ECG or LV strain pattern criteria, all patients underwent echocardiography and coronary angiography and the data were collected from patients’ files. Results: The records of 401 hypertensive patients [262(65.3%) males/139(34.7%) females] were included in this study. Their mean age was 60.07 ± 10.8 year. The relation between electrocardiographic left ventricular strain pattern and Coronary Angiography among patients was significant (P <0.001). There was a significant difference between electrocardiographic left ventricular strain pattern and cerebrovascular accident among studied group (P<0.001). Conclusions: electrocardiographic left ventricular strain in hypertensive patients is highly associated with coronary artery disease and cerebrovascular accident. .

A Healthy Young Lady with ‘Unprovoked’ Persistent Bilateral Pulmonary Embolism - Why?

Pulmonary embolism (PE) was reported in about 9% patients with antiphospholipid syndrome (APS). Seronegative APS is an entity which demonstrates clinical manifestations highly suggestive of APS but persistently negative APS antibodies. A 31-year-old lady presented with a two-month history of exertional dyspnoea. She had two consecutive miscarriages at 12 and 14 weeks, previously. Physical examination revealed a thin lady who was tachycardic, tachypneic, hypoxic but normotensive. There was a loud P2 without signs of heart failure. Investigations revealed a type 1 respiratory failure, sinus tachycardia with right ventricular strain pattern, cardiomegaly with normal lung fields, and dilated right atrium and right ventricle with increased in pulmonary arterial pressure of 70mmHg from echocardiography. CT pulmonary angiography (CTPA) confirmed the presence of PE over bilateral pulmonary arteries. She continued to have exertional dyspnoea and was readmitted 9 months later with worsening dyspnoea. APS antibodies performed during both admissions were negative. Seronegative APS was diagnosed. Interestingly, two CTPAs performed at 6 months and 9 months after initial presentation revealed persistent bilateral pulmonary embolism. The provoking factors for PE should be sought because ‘unprovoked’ PE especially in young individuals need further attention. APS, including seronegative APS, should be considered. Persistence of symptoms of PE also warrants further attention as chronic thromboembolic pulmonary hypertension (CTEPH) may be the cause. Currently, there are available medical and surgical treatment of CTEPH, therefore establishing its diagnosis is important and it is best performed in pulmonary hypertension expert centre.International Journal of Human and Health Sciences Supplementary Issue-2: 2021 Page: S25