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Introduction
I have recently started doing research in evolutionary psychology and environmental science.
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Publications
Publications (72)
This article examines the patriarchy through evolutionary psychology, economics, and biology (primarily hormones), suggesting it stems from adaptive strategies rather than from male dominance. Traits like male competitiveness and resource acquisition evolved to meet environmental and reproductive pressures, influenced by female mate selection. Simi...
this paper critically examines the scientific and ethical underpinnings of gender-affirming care, particularly for minors. While major medical organizations endorse such interventions as medically necessary, the evidence supporting their long-term safety and efficacy remains limited. Research into hormonal, neuroanatomic, and genetic influences rev...
The history of the universe, earth and life. Go to this link: https://www.imagella.com/products/origin-of-universe?_pos=1&_psq=voyage+of&_ss=e&_v=1.0
A look at why the Paris Accords has failed and why climate is not an existential threat
The composition and geochemical signatures of the mantle wedge beneath the Lesser Antilles arc are documented by the ultramafic xenoliths included in alkali basalts (M-series) on Grenada. Xenoliths consist of harzburgites, lherzolites, dunites and subordinate wehrlites and pyroxenites. Primary minerals phases are olivine, low-Al and high-Al orthopy...
Pliocene to recent volcanic rocks from the Bulusan volcanic complex in the southern part of the Bicol arc (Philippines) exhibit a wide compositional range (medium- to high-K basaltic-andesites, andesites and a dacite/rhyolite suite), but are characterised by large ion lithophile element enrichments and HFS element depletions typical of subduction-r...
Pliocene to recent volcanic rocks from the Bulusan volcanic complex in the southern part of the Bicol arc (Philippines) exhibit
a wide compositional range (medium- to high-K basaltic-andesites, andesites and a dacite/rhyolite suite), but are characterised
by large ion lithophile element enrichments and HFS element depletions typical of subduction-r...
We have performed Re–Os isotope measurements on a suite of 21 Kamchatka mantle xenoliths including 19 harzburgites and two lherzolites, from the northern arc front (Valovayam Volcano), the southern arc front (Avachinsky Volcano), and behind the arc front in the south (Bakening Volcano). Os and Re concentrations vary from 0.02 to 8.2 and 0.003 to 0....
We have performed Re–Os isotope measurements on a suite of 21 Kamchatka mantle xenoliths including 19 harzburgites
and two lherzolites, from the northern arc front (Valovayam Volcano), the southern arc front (Avachinsky Volcano), and behind
the arc front in the south (Bakening Volcano). Os and Re concentrations vary from 0.02 to 8.2 and 0.003 to 0....
To the best of our knowledge, modern adakites have not been documented in a nonarc environment. We report geochemical and isotopic data for Early Cretaceous Anjishan adakitic intrusive rocks that are in a continental setting unrelated to subduction. The Anjishan adakitic intrusive rocks, which are exposed in the Ningzhen area of east China, have hi...
Adakites were proposed over a decade ago to be products of the melting of young subducted oceanic crust. In fact, several new localities have been discovered since the original work documented approximately ten localities in modern arcs (e. g., southwestern Japan, Trans Mexican Volcanic Belt, etc.). But work over the past ten years has also shown t...
Ultramafic xenoliths from a veined mantle wedge beneath the Kamchatka arc have non-chondritic, fractionated chondrite-normalized platinum-group element (PGE) patterns. Depleted (e.g., low bulk-rock Al2O3 and CaO contents) mantle harzburgites show clear enrichment in the Pd group relative to the Ir group PGEs and, in most samples, Pt relative to Rh...
We are grateful for this opportunity to elaborate upon our ideas. R. Conrey has conveniently numbered his thoughts, and therefore, we will address them using his order. But first a few remarks about his general comments.
We have never implied that slab melting is a “common process” and that many arc volcanoes are composed “dominantly of adakite.” I...
Saba is the northernmost volcano along the Lesser Antilles island-arc chain. The Lesser Antilles arc results from the west-northwest subduction of the Atlantic lithosphere beneath the Caribbean Plate. Sediment thickness along the trench decreases northward away from sediment sources on the continent of South America. We focused our attention on Sab...
Most recent geology textbooks state that subduction-related volcanism is
due to the melting of the down-going lithosphere. However, for the last
30 years, few in the field have seriously believed that the subducting
slab is the source of arc basalts. The accepted hypothesis involves
melting of the mantle wedge above the slab via hydrous fluids prod...
Mantle-derived spinel harzburgites from the Kamchatka arc have fractionated Pd- group element patterns, and Pt is clearly enriched relative to Pd and Rh. This fractionation is also consistent with chondritic Ir-group platinum-group element distribution and super- chondritic Pt/Pd, chondrite-normalized (Pt/Os)N and (Pt/Ir)N found in harzburgite xeno...
Neogene and Quaternary lavas from Batan, Babuyan de Claro, Camiguin and Calayan islands (northern Luzon arc) display temporal increases in incompatible elements including Cs, Rb, Ba, K, La, Ce, Th, U, Ta, Hf, and Zr from volcanoes older than 3 Ma to younger ones. These enrichments occur either within a single island (Batan) or within an island grou...
The Kamchatka arc (Russia) is located in the northwestern Pacific Ocean and is divided into three segments by major sub-latitudinal fault zones (crustal discontinuities). The southern (SS) and central (CS) segments are associated with the subduction of old Pacific lithosphere, whereas the northern, inactive segment (NS) was formed during westward s...
The Pliocene—Pleistocene magmatic activity of the Zamboanga are is linked to the southward subduction of the Oligocene—Mio-cene Sulu Sea back-are basin along the Sulu Trench. The magmatic products include small amounts of adakites dated from 3.8 to 0.7 Ma, abundant Nb-enriched basalts and basaltic andesites (NEB) dated from 2 to 1 Ma and a lone cal...
The Pliocene (7 Ma) Nb-enriched arc basalts of the Valovayam Volcanic Field (VVF) in the northern segment of Kamchatka arc (Russia) host abundant xenoliths of spinel peridotites and pyroxenites. Textural and microstructural evidence for the high-temperature, multistage creep-related deformations in spinel peridotites supports a sub-arc mantle deriv...
Active volcanism in the Kamchatka arc occurs where the Pacific Plate subducts beneath the Kamchatka peninsula south of its junction with the Aleutian arc. Most volcanism occurs within the Central Kamchatka Depression (CKD), a large graben oriented parallel to the trench, and along the Eastern Volcanic Front (EVF), located south and east of the CKD...
The prospect of partial melting of the subducted oceanic crust to produce arc magmatism has been debated for over 30 years. Debate has centred on the physical conditions of slab melting and the lack of a definitive, unambiguous geochemical signature and petrogenetic process. Experimental partial melting data for basalt over a wide range of pressure...
Whole-rock and mineral-trace element data from a suite of ultramafic
xenoliths collected from several young volcanoes along the Kamchatka arc
suggest at least two stages of mantle-wedge metasomatism. Fluid-induced
cryptic metasomatism (stage I) was caused by shallow-level slab
devolatilization which introduced several fluid-dependent trace elements...
Adakites are intermediate or acidic magmatic rocks (andesites, dacites, rhyolites) found in subduction/collision zones. They are rich in hydrous minerals, apatite, zircon, titanite, and characterized by low concentrations of Y and heavy rare earth elements, high Sr/Y ratios and MORB-like isotopic signatures. These peculiarities are reproduced throu...
The Pliocene (7 Ma) Nb-enriched arc basalts of the Valovayam Volcanic Field (VVF) in the northern segment of the Kamchatka arc, Russia, host abundant mantle xenoliths, including spinel Iherzolites. Textural and microstructural evidence for high-temperature, multi-stage, creep-related deformations in spinel Iherzolites supports a sub-arc mantle deri...
The Late Miocene Talamanca Intrusive Suite (TIS) represents one of the youngest and most extensively exposed plutonic suites associated with orogenesis in the world. Rapid uplift associated with subduction of the Cocos Ridge (approx 5 Ma) is primarily responsible for exposing this plutonic core. In addition, a combination of Pleistocene glacial and...
Nisyros island is a calc-alkaline volcano, built up during the last 100 ka. The first cycle of its subaerial history includes the cone-building activity with three phases, each characterized by a similar sequence: (1) effusive and explosive activity fed by basaltic andesitic and andesitic magmas; and (2) effusive andextrusive activity fed by daciti...
Shallow subduction of the Cocos Ridge below southeastern Costa Rica has elevated the central segment of the Chorotega arc (the Cordillera de Talamanca) to heights over 3500 m. Rapid uplift and associated faulting exposed the remains of volcanic arcs predating the Quaternary volcanics that dominate in the northwestern and eastern segments of the Cho...
Early Tertiary volcanic clasts were collected from the streambed of the Rio Morti near the village of Morti, eastern Panama, as part of a reconnaissance study. The samples range from basalts to rhyolites. K-Ar dates cluster around 58 Ma. The phenocryst mineralogy of the samples is typical of that found in arc-related volcanics. The geochemistry of...
The Vyvenka volcanic field records a period of Neogene, subduction-related volcanism in northern Kamchatka. Most models describing the tectonic evolution of the northwest Pacific do not account for this type of Neogene volcanism because the main locus of Pacific/Kula-North American convergence switched to the Aleutian Ridge during Eocene time. The...
Fifty new oxygen isotopic analyses have been obtained on metasomatized peridotite nodules from Batan Island (Philippines) as well as on their host lavas and other upper Tertiary and Quaternary volcanic rocks from the northern part of the Luzon arc. They are used to investigate the possible mechanisms of the crustal component contribution which were...
Two contrasting conceptual models of the postcaldera magmatic system of the Bulusan volcanic complex are constructed on the basis of a synthesis of volcanological, petrochemical, and petrologic data. These models predict that hydrothermal convection below the complex will occur either in discrete, structurally-focused zones or over a much broader a...
Post-3Ma volcanics from the N Luzon arc exhibit systematic variations in 87Sr/86Sr (0.70327–0.70610), 143Nd/144Nd (0.51302–0.51229) and 208Pb*/206Pb* (0.981–1.035) along the arc over a distance of about 500 km. Sediments from the South China Sea west of the Manila Trench also exhibit striking latitudinal variations in radiogenic isotope ratios, and...
Adakite, found in both the eastern and western parts of Mindanao Island, Philippines, is a rare rock type, characterized by low heavy rare earth elements and Y contents together with high Sr/Y ratios, and is considered to be the result of the melting of young subducted oceanic crust, which leaves an eclogite residue. Pliocene-Quaternary adakites fr...
Mount St. Helens, 50 km to the west of Mount Adams and the main Cascade volcanic chain, is only 80 km above the subducting oceanic lithosphere. The elevated temperatures off the subducting slab, because of the close proximity of the Juan de Fuca Ridge to the trench,may induce slab melting at a depth of ˜80 km. Dacites from Mount St. Helens have geo...
ISLAND arc basalts are thought to derive from the melting of the wedge of mantle overlying the subducting slab1; hence, the composition of this mantle wedge, and the nature of any metasomatic fluids or magmas introduced from the slab, have been the subject of much speculation2-6. Most of the evidence bearing on these questions has been indirect, co...
Oblique aseismic subduction below western Panama and southeastern Costa Rica has produced Recent arc-related volcanism. The aseismicity is probably related to the subduction of relatively hot oceanic lithosphere. The volcanism throughout this region over the past 2 Ma has been quite distinct, consisting of felsic magmas (andesites to rhyolites but...
La Yeguada volcanioc complex (LYVC) is one of many major volcanoes that represent the extension of the Central American arc in western Panama and that have resulted from current oblique subduction south of Panama. There are two major phases of calc-alkaline volcanic activity at LYVC based on mapping and K-Ar radiometric dates. The first phase began...
Volcanism throughout the Luzon arc is associated with eastward subduction of the South China Sea floor along the Manila Trench. The southern section of the arc, the focus of this study, extends from the Lingayen-Dingalan fault to the small Islands just south of Luzon. Two segments appear to exist along this section of the arc the northern Bataan an...
The easternmost stratovolcano along the Central American arc is El Valle volcano, Panama. Several andesitic and dacitic lava
flows, which range in age 5–10 Ma, are termed the old group. After a long period of quiescence (approximately 3.4 Ma), volcanic
activity resumed approximately 1.55 Ma with the emplacement of dacitic domes and the deposition o...
Widespread arc tholeiitic and calc-alkaline volcanism characterized the geologic evolution of western Panama and southeastern Costa Rica in middle to late Miocene and Quaternary time. Volcanism was and is clearly associated with subduction of Nazca lithosphere. Geochemical data suggest that formation of mantle-wedge-derived melts and their differen...
The petrogenesis of trondhjemite-tonalite-dacite (TTD) involves all major petrologic models in various tectonic settings. A specific subtype of TTD, high-Al type, is the one most commonly associated with Archean gneiss terranes. This study demonstrates that Archean TTD crustal generation processes are also present in selected high-Al Phanerozoic TT...
The Luzon arc consists of a 1200 km chain of stratovolcanoes and volcanic necks stretching from Mindoro (13° N) to the Coastal Range of Taiwan (24° N). This study is concerned with three of the five major segments along the arc: the Northern Luzon, Babuyan, and Taiwan segments. The late Tertiary to Quaternary volcanics of these segments are primari...
The Macolod Corridor in southwestern Luzon is an approximately 40 km wide zone of still active intense Quarternary volcanism which perpendicularly crosses the Island in a NE-SW direction. The tectonic setting of the corridor is still somewhat questionable due to several not yet well understood major structural elements affecting southwestern Luzon....
Rocks with the geochemical characteristics of melts derived directly from subducted lithosphere are present in some modern island and continental arcs where relatively young and hot lithosphere is being subducted. These andesites, dacites, and sodic rhyolites or their intrusive equivalents are usually not associated with parental basaltic magmas. I...
We have used a computer model (TRACES) to simulate low pressure differentiation of natural basaltic magmas in an attempt to investigate the chemical dynamics of open system magmatic processes. Our results, in the form of simulated liquid lines of descent and the calculated equilibrium mineralogy, were determined for perfect fractional crystallizati...
Miocene (10 Ma) to Recent volcanism is associated with eastward subduction along the Manila Trench for some 1200 km from the Coastal Range in Taiwan south to Mindoro. We suggest calling this the "Luzon arc'. There are five distinct segments along this arc: Mindoro, Bataan, Northern Luzon, Babuyan, and Taiwan. The nature of volcanism throughout the...
The two latest volcanic pulses in western Panama occurred in the middle Miocene and Quaternary. At least two volcanoes have been active in historic times. A period of relative quiescence (almost 10 m.y) separates these pulses. The most recent volcanism has a calc-alkaline character. Geochemical trends in individual centers are consistent, but the s...
The Blakes Ferry pluton is a calc-alkaline pluton that is exposed in southwestern Randolph County, Alabama, U.S.A. The petrogenesis of the Blakes Ferry pluton has been a controversy for almost 15 years. A petrogenetically coherent model is presented, however, as a result of new mineral analyses and the examination of previous analytical data.Crysta...
The western Central Luzon volcanic system is associated with eastward subduction along the Manila Trench. Two arcs, the Bataan (BA) and the Mindoro (MA) arcs have resulted from this subduction and are separated by a NE-SW-oriented rift related zone of volcanism called the Macolod Corridor (MC). The BA consists of volcanism related to partial meltin...
Oligocene-Miocene plutonic rocks from the Philippine island arc are characterized by uniform 87Sr/86Sr isotopic ratios of 0.7035-0.7039. In contrast, volcanics erupted in the past 5 Ma in Central Luzon, Marinduque, and Mindoro have higher radiogenic Sr (0.7042-0.7054) and show regional variations in their Sr isotopic compositions. Volcanics of the...
The western Central Luzon arc is apparently a complex zone of volcanism and tectonism. The volcanoes of the northern segment of the arc (the Bataan arc, BA) fall along two semi-parallel lineaments, the Western Bataan Lineament (WBL) and the Eastern Bataan Lineament (EBL). This northern segment is cut off from the southern extension of the arc by a...
Luzon, the Philippines, is wedged between east- and west-directed subducting slabs. Westward subduction has resulted in pre-Miocene igneous rocks from northern Luzon characterized by 87Sr/86Sr and 143Nd/144Nd ratios typical of intra-oceanic arcs where sediment involvement is minor. In addition, Pliocene to Holocene volcanic eruptions of Sr and Nd i...
Pre-Miocene igneous rocks from the Philippine Island arc are characterised by 87Sr/86Sr and 143Nd/144Nd ratios typical for intra-oceanic island arcs where sediment involvement in the magma genesis was minor. Lead isotopic ratios are similar to Indian Ocean MORB. Pliocene to recent volcanics, however, have more radiogenic Sr and Pb and less radiogen...
Typescript. Thesis (Ph. D.)--Florida State University, 1985. Includes bibliographical references (leaves 313-331).
A classic tholeiitic, calc-alkaline, and shoshonitic island-arc sequence has developed in western Luzon, the Philippines, as a result of subduction defined by an eastward-dipping Benioff zone. A simple technique of standardizing the data allows chemical concentrations to be recast to ``andesite equivalent'' compositions. Based on the excellent line...
Typescript. Thesis (M.S.)--University of Alabama, 1980. Includes bibliographical references (leaves 59-67).
