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30-683: Magmatic activity of the Franklin Glacier Complex spanned roughly four million years from the Late Miocene to the Early Pleistocene , with the most recently identified volcanic eruption having taken place around 2.2 million years ago. The existence of thermal springs near the complex implies that magmatic heat is still present. It has therefore been of interest to geothermal exploration . The area lies in one of British Columbia's many territorial divisions called

60-558: A 1:75,000 geology map of the island, 6 maps (1:25,000) containing topography, street directory and geology, a sheet of cross section and a locality map. The difference found between the 1976 Geology of Singapore report include numerous formations found in literature between 1976 and 2009. These include the Fort Canning Boulder Beds and stretches of limestone. In the United Kingdom , the term geological map

90-649: A feature that is angled at 34 degrees below the horizontal at an angle that is just east of true south). The oldest preserved geologic map is the Turin papyrus (1150 BCE), which shows the location of building stone and gold deposits in Egypt. The earliest geologic map of the modern era is the 1771 "Map of Part of Auvergne, or figures of, The Current of Lava in which Prisms, Balls, Etc. are Made from Basalt. To be used with Mr. Demarest's theories of this hard basalt. Engraved by Messr. Pasumot and Daily, Geological Engineers of

120-403: A long "strike" line, which is perpendicular to the direction of greatest slope along the surface of the bed, and a shorter "dip" line on side of the strike line where the bed is going downwards. The angle that the bed makes with the horizontal, along the dip direction, is written next to the dip line. In the azimuthal system, strike and dip are often given as "strike/dip" (for example: 270/15, for

150-449: A strike of west and a dip of 15 degrees below the horizontal). Trend and plunge are used for linear features, and their symbol is a single arrow on the map. The arrow is oriented in the downgoing direction of the linear feature (the "trend") and at the end of the arrow, the number of degrees that the feature lies below the horizontal (the "plunge") is noted. Trend and plunge are often notated as PLUNGE → TREND (for example: 34 → 86 indicates

180-637: Is a sub-epoch of the Miocene Epoch made up of two stages . The Tortonian and Messinian stages comprise the Late Miocene sub-epoch, which lasted from 11.63 Ma ( million years ago ) to 5.333 Ma. The gibbons (family Hylobatidae) and orangutans (genus Pongo ) are the first groups to split from the line leading to the hominins , including humans , then gorillas (genus Gorilla ), and finally chimpanzees and bonobos (genus Pan ). The splitting date between hominin and chimpanzee lineages

210-425: Is gathered new geologic units may be defined). However, in areas where the bedrock is overlain by a significantly thick unconsolidated burden of till , terrace sediments , loess deposits, or other important feature, these are shown instead. Stratigraphic contour lines, fault lines, strike and dip symbols, are represented with various symbols as indicated by the map key. Whereas topographic maps are produced by

240-619: Is placed by some between 4 and 8 million years ago, that is, during the Late Miocene. This geochronology article is a stub . You can help Misplaced Pages by expanding it . Geologic map A geologic map or geological map is a special-purpose map made to show various geological features. Rock units or geologic strata are shown by color or symbols. Bedding planes and structural features such as faults , folds , are shown with strike and dip or trend and plunge symbols which give three-dimensional orientations features. Stratigraphic contour lines may be used to illustrate

270-549: Is substantially older than the neighbouring Silverthrone Caldera to the northwest. Immediately west of the Franklin Glacier Complex are a series of hot springs confined in valleys. At Canyon Lake, a hot spring feeds a small stream that flows into the southeastern end of that lake. A single temperature of 58 °C (136 °F) has been obtained from this spring while the Hoodoo Creek and Pinter spring temperatures remain unknown. The existence of these hot springs has made

300-586: Is used. The UK and Isle of Man have been extensively mapped by the British Geological Survey (BGS) since 1835; a separate Geological Survey of Northern Ireland (drawing on BGS staff) has operated since 1947. Two 1:625,000 scale maps cover the basic geology for the UK. More detailed sheets are available at scales of 1:250,000, 1:50,000 and 1:10,000. The 1:625,000 and 1:250,000 scales show both onshore and offshore geology (the 1:250,000 series covers

330-716: The Cordilleran Ice Sheet until its retreat about 13,000 years ago. Franklin Glacier has since undergone glacial retreat and expansion throughout the Holocene . It appears to have retreated significantly during the early Holocene warm period, followed by advancements 6,300, 5,400, 4,600, 4,100, 3,100, 2,400, 1,500, 800 and 600 years ago. The timing of expansions corresponded with cool summer temperatures, generally moist conditions and increased precipitation. Minimal geologic studies have been conducted at

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360-480: The United States , geologic maps are usually superimposed over a topographic map (and at times over other base maps) with the addition of a color mask with letter symbols to represent the kind of geologic unit . The color mask denotes the exposure of the immediate bedrock , even if obscured by soil or other cover. Each area of color denotes a geologic unit or particular rock formation (as more information

390-470: The 1:50,000 scale. Small scale thematic maps (1:1,000,000 to 1:100,000) are also produced covering geochemistry , gravity anomaly , magnetic anomaly , groundwater , etc. Although BGS maps show the British national grid reference system and employ an OS base map, sheet boundaries are not based on the grid. The 1:50,000 sheets originate from earlier 'one inch to the mile' (1:63,360) coverage utilising

420-619: The Coast Plutonic Complex. The complex lies on the overlapping trend of the Garibaldi and Pemberton volcanic belts , which were formed as a result of subduction zone magmatism along the Cascade Volcanic Arc in the last 29 million years. Two separate stages of magmatic activity have been identified at the Franklin Glacier Complex. The first magmatic stage about 6.8 million years ago involved

450-401: The Franklin Glacier Complex a target for geothermal exploration but little work has been conducted due to its remote location. The only performed exploration has been moderate geologic mapping . A 50  megawatt binary plant has been proposed at Canyon Lake. Mineral exploration at the Franklin Glacier Complex has occurred sporadically since at least the 1960s. The earliest recorded work

480-445: The Franklin Glacier Complex and its geology is therefore poorly known. It measures 6 km (3.7 mi) wide and 20 km (12 mi) long, covering a northwesterly elliptical area of 130 km (50 sq mi) . Volcanic rocks of the Franklin Glacier Complex consist predominantly of dacite breccia , minor dacite flows and a few hornblende andesite remnants. An absence of pumice , glassy blocks or bombs in

510-562: The King." This map is based on Nicolas Desmarest 's 1768 detailed study of the geology and eruptive history of the Auvergne volcanoes and a comparison with the columns of the Giant's Causeway of Ireland. He identified both landmarks as features of extinct volcanoes. The 1768 report was incorporated in the 1771 (French) Royal Academy of Science compendium. The first geological map of the U.S.

540-714: The Range 2 Coast Land District. Local relief exceeds 2,000 m (6,600 ft) with the 18 km (11 mi) long valley-filling Franklin Glacier originating from an icefield below the west face of Mount Waddington. It is part of the Waddington Range, a subrange of the Pacific Ranges which in turn are a subdivision of the Coast Mountains . The Franklin Glacier Complex was covered by

570-518: The breccia suggests that it may be of epiclastic origin, possibly formed during collapse and infilling of a caldera . The complex has therefore been described as a caldera or a cauldron subsidence. Heavy erosion of the volcanic rocks has exposed a series of biotite - quartz - porphyry , biotite quartz- feldspar -porphyry and quartz monzonite subvolcanic plutons and dike swarms . They intrude through fractured and hydrothermally altered Mesozoic to early Tertiary granitic and metamorphic rocks of

600-405: The central emplacement of an elongated quartz monzonite stock . At least five porphyry and transitional vein -type mineral occurrences were deposited during this period. A series of smaller intrusions were emplaced during the second magmatic stage 2.2 to 3.9 million years ago, at least some of which appear to have been feeders for the overlying volcanic pile. The Franklin Glacier Complex

630-400: The colors and symbols to be used for rocks of differing types and ages. Geologists take two major types of orientation measurements (using a hand compass like a Brunton compass ): orientations of planes and orientations of lines. Orientations of planes are measured as a "strike" and "dip", while orientations of lines are measured as a "trend" and "plunge". Strike and dip symbols consist of

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660-435: The eastern states of the present-day US. The first geologic map of Great Britain was created by William Smith in 1815 using principles ( Smith's laws ) first formulated by Smith. The first geological map of Singapore was produced in 1974, produced by the then Public Work Department. The publication includes a locality map, 8 map sheets detailing the topography and geological units, and a sheet containing cross sections of

690-478: The entire UK continental shelf ), whilst other scales generally cover exposures on land only. Sheets of all scales (though not for all areas) fall into two categories: The maps are superimposed over a topographic map base produced by Ordnance Survey (OS), and use symbols to represent fault lines, strike and dip or geological units, boreholes etc. Colors are used to represent different geological units. Explanatory booklets (memoirs) are produced for many sheets at

720-457: The island. Since 1974, for 30 years, there were many findings reported in various technical conferences on newfound geology islandwide, but no new publication was produced. In 2006, Defence Science & Technology Agency, with their developments in underground space promptly started a re-publication of the Geology of Singapore, second edition. The new edition that was published in 2009, contains

750-441: The pre-grid Ordnance Survey One Inch Third Edition as the base map. Current sheets are a mixture of modern field mapping at 1:10,000 redrawn at the 1:50,000 scale and older 1:63,360 maps reproduced on a modern base map at 1:50,000. In both cases the original OS Third Edition sheet margins and numbers are retained. The 1:250,000 sheets are defined using lines of latitude and longitude, each extending 1° north-south and 2° east-west. In

780-532: The surface of a selected stratum illustrating the subsurface topographic trends of the strata. Isopach maps detail the variations in thickness of stratigraphic units. It is not always possible to properly show this when the strata are extremely fractured, mixed, in some discontinuities, or where they are otherwise disturbed. Rock units are typically represented by colors. Instead of (or in addition to) colors, certain symbols can be used. Different geologic mapping agencies and authorities have different standards for

810-427: Was done by Kennco Exploration Limited with the staking of claims in a zone of copper - molybdenum mineralization associated with the quartz monzonite stock. This was followed by geological mapping, silt and soil geochemical sampling and 192 m (630 ft) of diamond drilling in seven short boreholes . Kennco conducted no further work which led to the eventual lapse of their mineral claims in 1976. The area

840-587: Was produced in 1809 by William Maclure . In 1807, Maclure undertook the self-imposed task of making a geological survey of the United States. He traversed and mapped nearly every state in the Union. During the rigorous two-year period of his survey, he crossed and recrossed the Allegheny Mountains some 50 times. Maclure's map shows the distribution of five classes of rock in what are now only

870-476: Was restaked later that year by United Mineral Services Limited who would conduct reconnaissance mapping and regional research. In 1987–1988, United Pacific Gold Limited performed trenching, mapping, geophysics , geochemical sampling and 785 m (2,575 ft) of diamond drilling in nine boreholes. Mineral claims were staked once again in 1996 by F. Onucki and J. R. Deighton for the purpose of locating reported high-grade silver mineralization. Franklin Glacier

900-589: Was skied by Canadian mountaineers Don and Phyllis Munday on July 22, 1930 while exploring and mapping glaciers of the Waddington Range. Don Munday named the glacier in 1927 for its association with the Franklin River which in turn was named after a Benjamin Franklin at Tatla Lake . 51°20′N 125°24′W  /  51.333°N 125.400°W  / 51.333; -125.400 Late Miocene The Late Miocene (also known as Upper Miocene )

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